ACS8510 Rev2.1 SETS Synchronous Equipment Timing Source for SONET or SDH Network Elements FINAL ADVANCED COMMUNICATIONS Description Features The ACS8510 is a highly integrated, single-chip solution for the Synchronous Equipment Timing Source (SETS) function in a SONET or SDH Network Element. The device generates SONET or SDH Equipment Clocks (SEC) and frame synchronization clocks. The ACS8510 is fully compliant with the required specifications and standards. Suitable for Stratum 3E*, 3, 4E and 4 SONET or SDH Equipment Clock (SEC) applications Meets AT&T, ITU-T, ETSI and Telcordia specifications Accepts 14 individual input reference clocks Generates 11 output clocks Supports Free-run, Locked and Holdover modes of operation Robust input clock source quality monitoring on all inputs Automatic hit-less source switchover on loss of input Phase build out for output clock phase continuity during input switchover and mode transitions Microprocessor interface - Intel, Motorola, Serial, Multiplexed, EPROM Programmable wander and jitter tracking attenuation 0.1 Hz to 20 Hz Support for Master/Slave device configuration alignment and hot/standby redundancy IEEE 1149.1 JTAG Boundary Scan Single +3.3 V operation, +5 V I/O compatible Operating temperature (ambient) -40°C to +85°C Available in 100 pin LQFP package The device supports Free-run, Locked and Holdover modes. It also supports all three types of reference clock source: recovered line clock, PDH network, and node synchronization. The ACS8510 generates independent SEC and BITS clocks, an 8 kHz Frame Synchronization clock and a 2 kHz Multi-Frame Synchronization clock. Two ACS8510 devices can be used together in a Master/Slave configuration mode allowing system protection against a single ACS8510 failure. A microprocessor port is incorporated, providing access to the configuration and status registers for device setup and monitoring. The ACS8510 supports IEEE 1149.1 JTAG boundary scan. Rev2.1 adds choice of edge alignment for 8kHz input, as well as a low jitter n x E1/DS1 output mode. Other minor changes are made, with all described in Appendix A. * Meets Holdover requirements, lowest bandwidth 0.1 Hz. Block Diagram Figure 1. Simple Block Diagram Inp ut Ports 2 x A MI 10 x TTL 2 x PECL/LV DS Programmable; 64/8kHz 2kHz 4kHz N x 8kHz 1.544/2.048MHz 6.48MHz 19.44MHz 25.92MHz 38.88MHz 51.84MHz 77.76MHz 155.52MHz TOUT4 selector Div ider Dig ital Loop Filter PFD DTO DPLL/Freq. Synthesis 14xSEC 9xS EC Monitors TOUT0 se lec tor PFD Div ider IEEE 1149.1 JTAG Dig ital Loop Filter DTO DPLL/F req. Synthesis MFrSync TCK TDI TMS TRS T TDO Outp ut Ports Chip C lock Generator Priority Table Register Set A PLL Frequency Dividers FrSync MFrSync 1 x A MI 6 x TTL 2 x PECL/LV DS Programmable: 64/8kHz 1.544/2.048MHz 3.088/4.096MHz 6.176/8.182MHz 12.352/16.384MHz 6.48MHz 19.44MHz 25.92MHz 38.88MHz 51.84MHz 77.76MHz 155.52MHz 311.04MHz 2kHz MFrSync 8kHz FrSync M icropro cessor Port TCXO (*OCXO) Revision 1.06/October 2002 Semtech Corp. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table of Contents List of Sections Description ................................................................................................................................................................................................ 1 Block Diagram ........................................................................................................................................................................................... 1 Features ..................................................................................................................................................................................................... 1 Table of Contents ...................................................................................................................................................................................... 2 Pin Diagram ............................................................................................................................................................................................... 5 Pin Descriptions ........................................................................................................................................................................................ 6 Functional Description ............................................................................................................................................................................. 9 Local Oscillator Clock ................................................................................................................................................................................... 10 ITU and ETSI Specification ............................................................................................................................................................. 10 Telcordia GR-1244 CORE Specification ....................................................................................................................................... 10 Crystal Frequency Calibration ...................................................................................................................................................... 10 Input Interfaces ............................................................................................................................................................................................. 10 Over-Voltage Protection .............................................................................................................................................................................. 10 Input Reference Clock Ports ....................................................................................................................................................................... 11 Input Wander and Jitter Tolerance .............................................................................................................................................................. 9 Output Clock Ports ........................................................................................................................................................................................ 12 Low Speed Output Clock (DPLL2) ................................................................................................................................................. 12 High Speed Output Clock (DPLL1) ............................................................................................................................................... 12 Frame Sync and Multi-Frame Sync Clocks (Part of DPLL1) ................................................................................................... 13 Low Jitter Multiple E1/DS1 Outputs ........................................................................................................................................... 13 Output Wander and Jitter ............................................................................................................................................................................ 13 Phase Variation ............................................................................................................................................................................................. 18 Phase Build Out ............................................................................................................................................................................................. 21 Microprocessor Interface ............................................................................................................................................................................. 21 Motorola Mode ................................................................................................................................................................................ 21 Intel Mode ........................................................................................................................................................................................ 21 Multiplexed Mode ........................................................................................................................................................................... 21 Serial Mode ...................................................................................................................................................................................... 21 EPROM Mode ................................................................................................................................................................................... 21 Register Set ..................................................................................................................................................................................... 22 Configuration Registers ................................................................................................................................................................. 22 Status Registers .............................................................................................................................................................................. 22 Register Access ............................................................................................................................................................................... 22 Interrupt Enable and Clear ......................................................................................................................................................................... 22 Register Map .................................................................................................................................................................................................. 23 Register Map Description ........................................................................................................................................................................... 27 Selection of Input Reference Clock Source ............................................................................................................................................. 36 Forced Control Selection ............................................................................................................................................................... 37 Automatic Control Selection ........................................................................................................................................................ 37 Ultra Fast Switching ....................................................................................................................................................................... 37 External Protection Switching ..................................................................................................................................................... 38 Clock Quality Monitoring ............................................................................................................................................................................. 38 Activity Monitoring ....................................................................................................................................................................................... 39 Frequency Monitoring .................................................................................................................................................................................. 39 Modes of Operation ...................................................................................................................................................................................... 41 Free-run mode ................................................................................................................................................................................. 41 Pre-Locked mode ............................................................................................................................................................................ 41 Locked mode .................................................................................................................................................................................... 41 Lost_Phase mode ........................................................................................................................................................................... 41 Holdover mode ................................................................................................................................................................................ 42 Pre-Locked(2) mode ........................................................................................................................................................................ 42 Protection Facility ........................................................................................................................................................................................ 43 Alignment of Priority Tables in Master and Slave ACS8510 ................................................................................................. 44 Alignment of the Selection of Reference Sources for TOUT4 Generation in the Master and Slave ACS8510 ........... 45 Alignment of the Phases of the 8kHz and 2kHz Clocks in both Master and Slave ACS8510 ....................................... 45 JTAG .................................................................................................................................................................................................................. 45 PORB ................................................................................................................................................................................................................ 45 Electrical Specification .......................................................................................................................................................................... 48 Revision 1.06/October 2002 Semtech Corp. 2 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS DC Characteristics: AMI Input/Output Port ........................................................................................................................................... 54 Microprocessor Interface Timing .......................................................................................................................................................... 63 Motorola Mode .............................................................................................................................................................................................. 63 Intel Mode ....................................................................................................................................................................................................... 65 Multiplexed Mode ......................................................................................................................................................................................... 67 Serial Mode .................................................................................................................................................................................................... 69 EPROM Mode ................................................................................................................................................................................................. 71 Package Information .............................................................................................................................................................................. 72 Thermal Conditions ....................................................................................................................................................................................... 73 Application Information .......................................................................................................................................................................... 74 Revision History ...................................................................................................................................................................................... 75 Ordering Information .............................................................................................................................................................................. 76 Disclaimers ..................................................................................................................................................................................................... 76 List of Figures Figure 1. Simple Block Diagram ............................................................................................................................................................. 1 Figure 2. ACS8510 Pin Diagram ............................................................................................................................................................ 5 Figure 3. Minimum Input Jitter Tolerance (OC-3/STM-1) ................................................................................................................... 15 Figure 4. Minimum Input Jitter Tolerance (DS1/E1) .......................................................................................................................... 16 Figure 5. Wander and Jitter Measured Transfer Characteristics ....................................................................................................... 18 Figure 6. Maximum Time Interval Error of TOUT0 output port ........................................................................................................... 20 Figure 7. Time Deviation of TOUT0 output port ................................................................................................................................... 20 Figure 8. Phase error accumulation of TOUT0 output port in Holdover mode .................................................................................. 20 Figure 9. Inactivity and Irregularity Monitoring ................................................................................................................................... 38 Figure 10. Master-Slave Schematic ..................................................................................................................................................... 46 Figure 11. Automatic Mode Control State Diagram ........................................................................................................................... 47 Figure 12. Recommended Line Termination for PECL Input/Output Ports ...................................................................................... 51 Figure 13. Recommended Line Termination for LVDS Input/Output Ports ...................................................................................... 53 Figure 14. Signal Structure of 64 kHz/8kHz Central Clock Interface ............................................................................................ 55 Figure 15. AMI Input and Output Signal Levels .................................................................................................................................. 55 Figure 16. Recommended Line Termination for AMI Output/Output Ports ..................................................................................... 56 Figure 17. JTAG Timing ............................................................................................................................................................................ 61 Figure 18. Input/Output Timing ............................................................................................................................................................ 62 Figure 19. Read Access Timing in MOTOROLA Mode ........................................................................................................................ 63 Figure 20. Write Access Timing in MOTOROLA Mode ....................................................................................................................... 64 Figure 21. Read Access Timing in INTEL Mode ................................................................................................................................... 65 Figure 22. Write Access Timing in INTEL Mode .................................................................................................................................. 66 Figure 23. Read Access Timing in MULTIPLEXED Mode .................................................................................................................... 67 Figure 24. Write Access Timing in MULTIPLEXED Mode ................................................................................................................... 68 Figure 25. Read Access Timing in SERIAL Mode ................................................................................................................................ 69 Figure 26. Write Access Timing in SERIAL Mode ............................................................................................................................... 70 Figure 27. Access Timing in EPROM Mode ......................................................................................................................................... 71 Figure 28. LQFP Package ...................................................................................................................................................................... 72 Figure 29. Typical 100 Pin LQFP Footprint ......................................................................................................................................... 73 Figure 30. Simplified Application Schematic ...................................................................................................................................... 74 Revision 1.06/October 2002 Semtech Corp. 3 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS List of Tables Table 1. Power Pins .................................................................................................................................................................................... 6 Table 2. No Connections ............................................................................................................................................................................ 6 Table 3. Other Pins ..................................................................................................................................................................................... 7 Table 4. Input Reference Source Selection and Priority Table .......................................................................................................... 12 Table 5. Input ReferenceSource Jitter Tolerance ................................................................................................................................. 14 Table 6. Amplitude and Frequency Values for Jitter Tolerance ............................................................................................................ 15 Table 7. Amplitude and Frequency Values for Jitter Tolerance ............................................................................................................ 16 Table 8. Output Reference Source Selection Table ............................................................................................................................. 17 Table 9. Multiple E1/DS1 Output in Relation to Normal Outputs ..................................................................................................... 17 Table 10. Microprocessor Interface Mode Selection ......................................................................................................................... 21 Table 11. Register Map .......................................................................................................................................................................... 23 Table 12. Register Map Description ..................................................................................................................................................... 27 Table 13. Master-Slave Relationship .................................................................................................................................................... 46 Table 14. Absolute Maximum Ratings .................................................................................................................................................. 48 Table 15. Operating Conditions ............................................................................................................................................................. 48 Table 16. DC Characteristics: TTL Input Port ....................................................................................................................................... 48 Table 17. DC Characteristics: TTL Input Port with Internal Pull-up .................................................................................................... 49 Table 18. DC Characteristics: TTL Input Port with Internal Pull-down ............................................................................................... 49 Table 18. DC Characteristics: TTL Output Port .................................................................................................................................... 49 Table 20. DC Characteristics: PECL Input/Output Port ...................................................................................................................... 50 Table 21. DC Characteristics: LVDS Input/Output Port ...................................................................................................................... 52 Table 22. DC Characteristics: AMI Input/Output Port ........................................................................................................................ 54 Table 23. DC Characteristics: Ouput Jitter Generation (Test Definition G.813) ............................................................................. 57 Table 24. DC Characteristics: Ouput Jitter Generation (Test Definition G.812) ............................................................................. 57 Table 25. DC Characteristics: Ouput Jitter Generation (Test Definition ETS-300-462-3) .............................................................. 58 Table 26. DC Characteristics: Ouput Jitter Generation (Test Definition GR-253-CORE) ............................................................... 58 Table 27. DC Characteristics: Ouput Jitter Generation (Test Definition AT&T 62411) ................................................................... 59 Table 28. DC Characteristics: Ouput Jitter Generation (Test Definition G.742) .............................................................................. 59 Table 29. DC Characteristics: Ouput Jitter Generation (Test Definition TR-NWT-000499) ........................................................... 59 Table 30. DC Characteristics: Ouput Jitter Generation (Test Definition GR-1244-CORE) ............................................................. 60 Table 31. JTAG Timing (for use with Figure 17) ................................................................................................................................... 61 Table 32. Read Access Timing in MOTOROLA Mode (for use with Figure 19) ................................................................................. 63 Table 33. Write Access Timing in MOTOROLA Mode (for use with Figure 20) ................................................................................ 64 Table 34. Read Access Timing in INTEL Mode (for use with Figure 21) ............................................................................................ 65 Table 35. Write Access Timing in INTEL Mode (for use with Figure 22) ........................................................................................... 66 Table 36. Read Access Timing in MULTIPLEXED Mode (for use with Figure 23) ............................................................................. 67 Table 37. Write Access Timing in MULTIPLEXED Mode (for use with Figure 24) ............................................................................. 68 Table 38. Read Access Timing in SERIAL Mode (for use with Figure 25) ......................................................................................... 70 Table 39. Write Access Timing in SERIAL Mode (for use with Figure 26) ........................................................................................ 70 Table 40. Access Timing in EPROM Mode (for use with Figure 27) .................................................................................................. 71 Table 41. 100 Pin LQFP Package Dimension Data (for use with Figure 28) ................................................................................... 73 Revision 1.06/October 2002 Semtech Corp. 4 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Pin Diagram Figure 2. ACS8510 Pin Diagram 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 AGND TRST IC NC AGND VA1+ TMS INTREQ TCK REFCLK DGND VD+ VD+ DGND DGND VD+ NC SRCSW VA2+ AGND TDO IC TDI I1 I2 VAMI+ TO8NEG TO8POS GND_AMI FrSync MFrSync GND_DIFF VDD_DIFF TO6POS TO6NEG TO7POS TO7NEG GND_DIFF VDD_DIFF I5POS I5NEG I6POS I6NEG VDD5 SYNC2K I3 I4 I7 DGND VDD 1 ACS8510 SDH/SONET SETS Rev 2.1 NC - Not Connected; leave to Float. IC - Internally Connected; leave to Float. Revision 1.06/October 2002 Semtech Corp. 5 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 SONSDHB MSTSLVB IC IC IC TO9 TO5 TO4 DGND VDD TO3 TO2 TO1 DGND VDD VDD DGND AD0 AD1 AD2 AD3 AD4 AD5 AD6 AD7 RDY PORB ALE RDB WRB CSB A0 A1 A2 A3 A4 A5 A6 DGND VDD UPSEL0 UPSEL1 UPSEL2 I14 I13 I12 I11 I10 I9 I8 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Pin Descriptions Table 1. Power Pins PIN SYM B OL IO T YPE N A M E /DE SCR I P T I O N 12, 13, 16 VD+ P - S u p p l y v ol t ag e: Digital sup p ly to gates in analog section, +3.3 Volts. +/- 10% 26 VAMI+ P - S u p p l y v ol t ag e : Digital sup p ly to AMI outp ut, +3.3 Volts. +/- 10% 33, 39 VDD_DIFF P - S u p p l y v ol t ag e : Digital sup p ly for differential p or ts, +3.3 Volts. +/- 10% 44 VDD5 P - V D D 5: Digital sup p ly for +5 Volts tolerance to inp ut p ins. Connect to +5 Volts (+/- 10%) for clamp ing to +5 Volts. Connect to VDD for clamp ing to +3.3 Volts. Leave floating for no clamp ing, inp ut p ins tolerant up to +5.5 Volts. 50, 61, 85, 86, 91 VDD P - S u p p l y v ol t ag e : Digital sup p ly to logic, +3.3 Volts. +/- 10% 6 VA1+ P - S u p p l y v ol t ag e: Analog sup p ly to clock multip ying PLL, +3.3 Volts. +/- 10% 19 VA2+ P - S u p p l y v ol t ag e : Analog sup p ly to outp ut PLL, +3.3 Volts. +/- 10% 11, 14, 15, 49, 62, 84, 87, 92 DGN D P - S u p p l y G r ou n d : Digital ground for logic 29 GN D_AMI P - S u p p l y G r ou n d : Digital ground for AMI outp ut 32, 38 GN D_DIFF P - S u p p l y G r ou n d : Digital ground for differential p or ts 1, 5, 20 AGN D P - S u p p l y G r ou n d : Analog ground Table 2. No Connections PIN SYM B OL IO T YPE N A M E /DE SCR I P T I O N 4, 17 NC - - N ot C on n ect ed : Leave to Float 3, 22, 96, 97,98 IC - - I n t er n al l y C on n ect ed : Leave to Float Note: I = input, O = output, P = power, TTLU = TTL input with pull-up resistor, TTLD = TTL input with pull-down resistor Revision 1.06/October 2002 Semtech Corp. 6 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 3. Other Pins PIN SYM B OL IO T YPE N A M E /DE SCR I P T I O N 2 TRST I T T LD J TA G C o n t r o l R e se t I n p u t : TRST = 1 to enab le JTA G Bound ary Scan mod e. TRST = 0 for normal d evice op eration (JTA G logic transp arent). If not used connect to GN D or leave floating. 7 T MS I T T LU J TA G Te st M o d e S e l e ct : Bound ary Scan enab le. Samp led on rising ed ge of TCK. If not used connect to V DD or leave floating. 8 IN T R E Q O TTL CMOS I n t e r r u p t R e q u e st : A ctive h igh softw are Interrup t outp ut 9 TCK I T T LD J TA G C l o ck : Bound ary Scan clock inp ut. If not used connect to GN D or leave floating. Th is p in may req uire a cap acitor p laced b etw een th e p in and th e nearest GN D, to red uce noise p ickup . A value of 10 p F sh ould b e ad eq uate, b ut th e value is d ep end ent on PCB layout. 10 REFCLK I TTL R e f e r e n ce C l o ck : 12.8 MHz (refer to section h ead ed Local Oscillator Clock) 18 SRCSW I T T LD S o u r ce S w i t ch i n g : Force Fast Source Sw itch ing 21 TDO O TTL CMOS 23 TDI I T T LU J TA G I n p u t : Serial test d ata Inp ut. Samp led on rising ed ge of TCK. If not used connect to V DD or leave floating. 24 I1 I A MI I n p u t r e f e r e n ce 1: comp osite clock 64 kHz + 8 kHz 25 I2 I A MI I n p u t r e f e r e n ce 2: comp osite clock 64 kHz + 8 kHz 27 TO8N EG O A MI O u t p u t r e f e r e n ce 8: comp osite clock, 64 kHz + 8 kHz negative p ulse 28 TO8POS O A MI O u t p u t r e f e r e n ce 8: comp osite clock, 64 kHz + 8 kHz p ositive p ulse 30 FrSync O TTL CMOS O u t p u t r e f e r e n ce 10: 8 kHz Frame Sync clock outp ut (sq uare w ave) 31 MFrSync O TTL CMOS O u t p u t r e f e r e n ce 11: 2 kHz Multi-Frame Sync clock outp ut (sq uare w ave) 34 35 TO6POS TO6N EG O LV DS PECL O u t p u t r e f e r e n ce 6: d efault 38.88 MHz. A lso Dig1 (1.544 MHz/2.048 MHz and 2, 4, 8 x), 19.44 MHz, 155.52 MHz, 311.04 MHz. Default typ e LV DS. 36 37 TO7POS TO7N EG O PECL LV DS O u t p u t r e f e r e n ce 7: d efault 19.44 MHz. A lso 51.84 MHz, 77.76 MHz, 155.52 MHz. Default typ e PECL. 40 41 I5POS I5N EG I LV DS PECL I n p u t r e f e r e n ce 5: d efault 19.44 MHz, d efault typ e LV DS 42 43 I6POS I6N EG I PECL LV DS I n p u t r e f e r e n ce 6: d efault 19.44 MHz, d efault typ e PECL Revision 1.06/October 2002 Semtech Corp. J TA G O u t p u t : Serial test d ata outp ut. Up d ated on falling ed ge of TCK. If not used leave floating. 7 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 3. Other Pins (continued) PIN SYM B OL IO T YPE N A M E /DE SCR I P T I O N 45 SYN C2K I T T LD S y n ch r o n i se 2 k H z : Connect to 2 kHz Multi-Frame Sync outp ut of p ar tner A CS8510 in red und ancy system 46 I3 I T T LD I n p u t r e f e r e n ce 3: p rogrammab le, d efault 8 kHz 47 I4 I T T LD I n p u t r e f e r e n ce 4: p rogrammab le, d efault 8 kHz 48 I7 I T T LD I n p u t r e f e r e n ce 7: p rogrammab le, d efault 19.44 MHz 51 I8 I T T LD I n p u t r e f e r e n ce 8: p rogrammab le, d efault 19.44 MHz 52 I9 I T T LD I n p u t r e f e r e n ce 9: p rogrammab le, d efault 19.44 MHz 53 I10 I T T LD I n p u t r e f e r e n ce 10: p rogrammab le, d efault 19.44 MHz. 54 I11 I T T LD I n p u t r e f e r e n ce 11: p rogrammab le, d efault (master mod e)1.544/2.048 MHz, d efault (slave mod e) 6.48 MHz 55 I12 I T T LD I n p u t r e f e r e n ce 12: p rogrammab le, d efault 1.544/2.048 MHz. 56 I13 I T T LD I n p u t r e f e r e n ce 13: p rogrammab le, d efault 1.544/2.048 MHz. 57 I14 I T T LD I n p u t r e f e r e n ce 14: p rogrammab le, d efault 1.544/2.048 MHz. 58 - 60 UPSEL(2:0) I T T LD M i cr o p r o ce sso r se l e ct : Configures th e inter face for a p ar ticular microp rocessor typ e. 63 - 69 A (6:0) I T T LD M i cr o p r o ce sso r I n t e r f ace A d d r e ss: A d d ress b us for th e microp rocessor inter face registers. A (0) is SDI in Serial mod e. 70 CSB I T T LU C h i p S e l e ct ( A ct i v e L o w ) : Th is p in is asser ted Low b y th e microp rocessor to enab le th e microp rocessor inter face. 71 WRB I T T LU W r i t e ( A ct i v e L o w ) : Th is p in is asser ted Low b y th e microp rocessor to initiate a w rite cycle. In Motorola mod e, WRB = 1 for Read . 72 RDB I T T LU R e ad ( A ct i v e L o w ) : Th is p in is asser ted Low b y th e microp rocessor to initiate a read cycle. 73 A LE I T T LD A d d r e ss L at ch E n ab l e: Th is p in b ecomes th e ad d ress latch enab le from th e microp rocessor. Wh en th is p in transitions from Low to High , th e ad d ress b us inp uts are latch ed into th e internal registers. A LE = SCLK in Serial mod e. 74 PORB I T T LU P o w e r O n R e se t : Master reset. If PORB is forced Low, all internal states are reset b ack to d efault values. 75 RDY O TTL CMOS R e ad y / D at a ack n o w l e d g e: Th is p in is asser ted High to ind icate th e d evice h as comp leted a read or w rite op eration. 76 - 83 A D(7:0) IO T T LD A d d r e ss/ D at a: Multip lexed d ata/ad d ress b us d ep end ing on th e microp rocessor mod e selection. A D(0) is SDO in Serial mod e. Revision 1.06/October 2002 Semtech Corp. 8 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 3. Other Pins (continued) PIN SYM B OL IO T YPE 88 TO1 O TTL CMOS O u t p u t r e f e r e n ce 1: d efault 6.48 MHz. A lso Dig1 (1.544 MHz/2.048 MHz and 2, 4, 8 x), 19.44 MHz, 25.92 MHz 89 TO2 O TTL CMOS O u t p u t r e f e r e n ce 2: d efault 38.88 MHz. A lso Dig2 (1.544 MHz/2.048 MHz and 2, 4, 8 x), 25.92 MHz, 51.84 MHz 90 TO3 O TTL CMOS O u t p u t r e f e r e n ce 3: 19.44 MHz - fixed . 93 TO4 O TTL CMOS O u t p u t r e f e r e n ce 4: 38.88 MHz - fixed . 94 TO5 O TTL CMOS O u t p u t r e f e r e n ce 5: 77.76 MHz - fixed . 95 TO9 O TTL CMOS O u t p u t r e f e r e n ce 9: 1.544/2.048 MHz. (T4 BITS) 99 100 MSTSLV B SON SDHB I I N A M E /DE SCR I P T I O N TTLU M A S T E R S L AV E B : Master slave select: sets th e initial p ow er up state (or state after a PORB) of th e Master/Slave selection register, ad d r 34, b it 1. Th e register state can b e ch anged after p ow er up b y softw are. T T LD S O N E T S D H B : SON ET or SDH freq uency select: sets th e initial p ow er up state (or state after a PORB) of th e SON ET/SDH freq uency selection registers, ad d r 34h , b it 2 and ad d r 38, b its 5 and 6. Th e register states can b e ch anged after p ow er up b y softw are. Functional Description The ACS8510 is a highly integrated, single-chip solution for the SETS function in a SONET/SDH Network Element, for the generation of SEC and frame synchronization pulses. In Free-run mode, the ACS8510 generates a stable, lownoise clock signal from an internal oscillator. In Locked mode, the ACS8510 selects the most appropriate input reference source and generates a stable, low-noise clock signal locked to the selected reference. In Holdover mode, the ACS8510 generates a stable, low-noise clock signal from the internal oscillator, adjusted to match the last known good frequency of the last selected reference source. In all modes, the frequency accuracy, jitter and drift performance of the clock meet the requirements of ITU G.812, G.813, G.823, and GR-1244-CORE. Revision 1.06/October 2002 Semtech Corp. 9 The ACS8510 supports all three types of reference clock source: recovered line clock (TIN1), PDH network synchronization timing (TIN2) and node synchronization (TIN3). The ACS8510 generates independent TOUT0 and TOUT4 clocks, an 8 kHz Frame Synchronization clock and a 2 kHz Multi-Frame Synchronization clock. The ACS8510 has a high tolerance to input jitter and wander. The jitter/wander transfer is programmable (0.1 Hz up to 20 Hz cut-off points). The ACS8510 supports protection. Two ACS8510 devices can be configured to provide protection against a single ACS8510 failure. The protection maintains alignment of the two ACS8510 devices (Master and Slave) and ensures that both ACS8510 devices maintain the same priority table, choose the same www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS reference input and generate the TOUT0 clock, the 8 kHz Frame Synchronization clock and the 2 kHz Multi-Frame Synchronization clock with the same phase. The ACS8510 includes a microprocessor port, providing access to the configuration and status registers for device setup and monitoring. Local Oscillator Clock The Master system clock on the ACS8510 should be provided by an external clock oscillator of frequency 12.80 MHz. The clock specification is important for meeting the ITU/ETSI and Telcordia performance requirements for Holdover mode. ITU and ETSI specifications permit a combined drift characteristic, at constant temperature, of all non-temperaturerelated parameters, of up to 10 ppb per day. The same specifications allow a drift of 1 ppm over a temperature range of 0 to +70 °C. Telcordia specifications are somewhat tighter, requiring a non-temperature-related drift of less than 40 ppb per day and a drift of 280 ppb over the temperature range 0 to +50 °C. ITU and ETSI Specification Crystal Frequency Calibration The absolute crystal frequency accuracy is less important than the stability since any frequency offset can be compensated by adjustment of register values in the IC. This allows for calibration and compensation of any crystal frequency variation away from its nominal value. +/- 50 ppm adjustment would be sufficient to cope with most crystals, in fact the range is an order of magnitude larger due to the use of two 8 bit register locations. The setting of the conf_nominal_frequency register allows for this adjustment. An increase in the register value increases the output frequencies by 0.02 ppm for each LSB step. The default value (in decimal) is 39321. The minimum being 0 and the maximum 65535, gives a -700 ppm to +500 ppm adjustment range of the output frequencies. For example, if the crystal was oscillating at 12.8 MHz + 5 ppm, then the calibration value in the register to give a -5 ppm adjustment in output frequencies to compensate for the crystal inaccuracy, would be : 39321 - (5 / 0.02) = 39071 (decimal) Tolerance: +/- 4.6 ppm over 20 year life time. Drift*: +/- 0.05 ppm/15 seconds @ constant temp. Input Interfaces +/- 0.01 ppm/day @ constant temp. The ACS8510 supports up to fourteen input reference clock sources from input types TIN1, TIN2 and TIN3 using TTL, CMOS, PECL, LVDS and AMI buffer I/O technologies. These interface technologies support +3.3 V and +5 V operation. +/- 1 ppm over temp. range 0 to +70 °C *Frequency drift over supply range of +2.7V to +3.3V. Telcordia GR-1244 CORE Specification Tolerance: +/- 4.6 ppm over 20 year life time. Drift*: +/- 0.05 ppm/15 seconds @ constant temp. Over-Voltage Protection +/- 0.04 ppm/day @ constant temp. +/- 0.28 ppm over temp. range 0 to +50 °C *Frequency drift over supply range of +2.7V to +3.3V. Please contact Semtech for information on crystal oscillator suppliers. Revision 1.06/October 2002 Semtech Corp. 10 The ACS8510 may require Over-Voltage Protection on input reference clock ports according to ITU Recommendation K.41. Semtech protection devices are recommended for this purpose (see separate Semtech data book). www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Input Reference Clock Ports Table 4 gives details of the input reference ports, showing the input technologies and the range of frequencies supported on each port; the default spot frequencies and default priorities assigned to each port on power-up or by reset are also shown. Note that SDH and SONET networks use different default frequencies; the network type is pin-selectable (using the SONSDHB pin). Specific frequencies and priorities are set by configuration. Although each input port is shown as belonging to one of the types, TIN1, TIN2 or TIN3, they are fully interchangeable as long as the selected speed is within the maximum operating speed of the input port technology. SDH and SONET networks use different default frequencies; the network type is selectable using the config_mode register 34 Hex, bit 2. For SONET, config_mode register 34 Hex, bit 2 = 1, for SDH config_mode register 34 Hex, bit 2 = 0. On power-up or by reset, the default will be set by the state of the SONSDHB pin (pin 100). Specific frequencies and priorities are set by configuration. TTL ports (compatible also with CMOS signals) support clock speeds up to 100 MHz, with the highest spot frequency being 77.76 MHz. The actual spot frequencies supported are: 2 kHz 4 kHz 8 kHz (and N x 8 kHz) 1.544 MHz (SONET)/2.048 MHz (SDH) 6.48 MHz, 19.44 MHz, 25.92 MHz, 38.88 MHz, 51.84 MHz, 77.76 MHz. Revision 1.06/October 2002 Semtech Corp. 11 The frequency selection is programmed via the cnfg_ref_source_frequency register. The internal DPLL will normally lock to the selected input at the frequency of the input, eg. 19.44 MHz will lock the DPLL phase comparisons at 19.44 MHz. It is, however, possible to utilise an internal pre-divider to the DPLL to divide the input frequency before it is used for phase comparisons in the DPLL. This pre-divider can be used in one of 2 ways: 1. Any of the supported spot frequencies can be divided to 8 kHz by setting the lock8K bit (bit 6) in the appropriate cnfg_ref_source_frequency register location. For good jitter tolerance for all frequencies and for operation at 19.44 MHz and above, use lock8K. It is possible to choose which edge of the 8kHz input to lock to, by setting the appropriate bit of the cnfg_control1 register. 2. Any multiple of 8 kHz between 1544 kHz to 100 MHz can be supported by using the DivN feature (bit 7 of the cnfg_ref_source_frequency register). Any reference input can be set to use DivN independently of the frequencies and configurations of the other inputs. Any reference input with the DivN bit set in the cnfg_ref_source_frequency register will employ the internal pre-divider prior to the DPLL locking. The cnfg_freq_divn register contains the divider ratio N where the reference input will get divided by (N+1) where 0<N<2 14 -1. The cnfg_ref_source_frequency register must be set to the closest supported spot frequency to the input frequency, but must be lower than the input frequency. When using the DivN feature the post-divider frequency must be 8 kHz, which is indicated by setting the lock8k bit high (bit 6 in cnfg_ref_source_frequency register). Any input set to DivN must have the frequency monitors disabled (If the frequency monitors are disabled, they are disabled for all inputs regardless of the input configurations, in this case only activity monitoring will take place). Whilst any number of inputs can be set to use the DivN feature, only one N can be programmed, hence all inputs using the DivN feature must require the same division to get to 8 kHz. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 4. Input Reference Source Selection and Priority Table P or t N u m b er C h an n e l N u m b er P or t Ty p e I n p u t P or t Te c h n o l o g y I_1 0001 T IN 3 A MI 64/8kHz (comp osite clock, 64kHz + 8kHz) Default (SON ET): 64/8kHz Default (SDH): 64/8kHz 2 I_2 0010 T IN 3 A MI 64/8kHz (comp osite clock, 64kHz + 8kHz) Default (SON ET): 64/8kHz Default (SDH): 64/8kHz 3 I_3 0011 T IN 3 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 8kHz Default (SDH): 8kHz 4 I_4 0100 T IN 3 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 8kHz Default (SDH): 8kHz 5 I_5 0101 T IN 1 LVDS/PECL LVDS default Up to 155.52MHz (see N ote 2) Default (SON ET): 19.44MHz Default (SDH): 19.44MHz 6 I_6 0110 T IN 1 PECL/LVDS PECL default Up to 155.52MHz (see N ote 2) Default (SON ET): 19.44MHz Default (SDH): 19.44MHz 7 I_7 0111 T IN 1 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 19.44MHz Default (SDH): 19.44MHz 8 I_8 1000 T IN 1 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 19.44MHz Default (SDH): 19.44MHz 9 I_9 1001 T IN 1 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 19.44MHz Default (SDH): 19.44MHz 10 I_10 1010 T IN 1 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 19.44MHz Default (SDH): 19.44MHz 11 12/1 (N ote 3) Fr eq u en ci es S u p p or t ed D e f au l t P ri ori t y I_11 1011 T IN 2 TTL/CMOS Up to 100MHz (see N ote 1) Default (Master) (SON ET): 1.544MHz Default (Master) (SDH): 2.048MHz Default (Slave) 6.48MHz I_12 1100 T IN 2 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 1.544MHz Default (SDH): 2.048MHz 13 I_13 1101 T IN 2 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 1.544MHz Default (SDH): 2.048MHz 14 I_14 1110 T IN 2 TTL/CMOS Up to 100MHz (see N ote 1) Default (SON ET): 1.544MHz Default (SDH): 2.048MHz 15 Revision 1.06/October 2002 Semtech Corp. 12 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Notes for Table 4. Note 1: TTL ports (compatible also with CMOS signals) support clock speeds up to 100 MHz, with the highest spot frequency being 77.76 MHz. The actual spot frequencies are: 2 kHz, 4 kHz, 8 kHz (and N x 8 kHz), 1.544 MHz (SONET)/2.048 MHz (SDH), 6.48 MHz, 19.44 MHz, 25.92 MHz, 38.88 MHz, 51.84 MHz, 77.76 MHz. SONET or SDH is selected using the SONSDHB pin. When the SONSDHB pin is High SONET is selected, when the SONSDHB pin is Low SDH is selected. Note 2: PECL and LVDS ports support the spot clock frequencies listed above plus 155.52 MHz and 311.04 MHz. Note 3: Input port <I_11> is set at 12 on the Master SETS IC and 1 on the Slave SETS IC, as default on power up (or PORB). The default setup of Master or Slave <I_11> priority is determined by the MSTSLVB pin. DivN examples To lock to 2.000 MHz. (1) The cnfg_ref_source_frequency register is set to 11XX0001 (binary) to set the DivN, lock8k bits, and the frequency to E1/DS1. (XX = leaky bucket ID for this input). (2) The cnfg_mode register (34Hex) bit 2 needs to be set to 1 to select SONET frequencies (DS1). (3) The frequency monitors are disabled in cnfg_monitors register (48Hex) by writing 00 to bits 0 and 1. (4) The DivN register is set to F9 Hex (249 decimal). To lock to 10.000 MHz. (1) The cnfg_ref_source_frequency register is set to 11XX0010 (binary) to set the DivN, lock8k bits, and the frequency to 6.48 MHz. (XX = leaky bucket ID for this input). (2) The frequency monitors are disabled in cnfg_monitors register (48Hex) by writing 00 to bits 0 and 1. (3) The DivN register is set to 4E1 Hex (1249 decimal). PECL and LVDS ports support the spot clock frequencies listed plus 155.52 MHz and 311.04 MHz. The choice of PECL or LVDS compatibility is programmed via the cnfg_differential_inputs register. Unused PECL/ LVDS differential inputs should be fixed with one input high (VDD) and the other input low (GND), or set in LVDS mode and left floating, in which case one input is internally pulled high and the other low. An AMI port supports a composite clock, consisting of a 64 kHz AMI clock with 8 kHz boundaries marked by deliberate violations of the AMI coding rules, as specified in ITU recommendation G.703. Departures from the nominal pattern are detected within the Revision 1.06/October 2002 Semtech Corp. 13 ACS8510, and may cause reference-switching if too frequent. See section DC Characteristics: AMI Input/Output Port, for more details. If the AMI port is unused, the pins (I1 and I2) should be tied to GND and the VAMI+ supply pin (pin 26) disconnected. Input Wander and Jitter Tolerance The ACS8510 is compliant to the requirements of all relevant standards, principally ITU Recommendation G.825, ANSI DS1.101-1994 and ETS 300 462-5 (1997). All reference clock inputs have a tight frequency tolerance but a generous jitter tolerance. Pullin, hold-in and pull-out ranges are specified for each input port in Table 5. Minimum jitter www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS tolerance masks are specified in Figures 3 and 4, and Tables 6 and 7, respectively. The ACS8510 will tolerate wander and jitter components greater than those shown in Figure 3 and Figure 4, up to a limit determined by a combination of the apparent long-term frequency offset caused by wander and the eye-closure caused by jitter (the input source will be rejected if the offset pushes the frequency outside the hold-in range for long enough to be detected, whilst the signal will also be rejected if the eye closes sufficiently to affect the signal purity). The 8klocking mode should be engaged for high jitter tolerance according to these masks. All reference clock ports are monitored for quality, including frequency offset and general activity. Single short-term interruptions in selected reference clocks may not cause rearrangements, whilst longer interruptions, or multiple, short-term interruptions, will cause rearrangements, as will frequency offsets which are sufficiently large or sufficiently long to cause loss-of-lock in the phase-locked loop. The failed reference source will be removed from the priority table and declared as unserviceable, until its perceived quality has been restored to an acceptable level. The registers sts_curr_inc_offset (address 0C, 0D, 07) report the frequency of the DPLL with respect to the external TCXO frequency. This is a 19 bit signed number with one LSB representing 0.0003 ppm (range of +/- 80 ppm). Reading this regularly can show how the currently locked source is varying in value e.g. due to wander on its input. The ACS8510 performs automatic frequency monitoring with an acceptable input frequency offset range of +/- 16.6 ppm. The ACS8510 DPLL has a programmable frequency limit of +/- 80 ppm. If the range is programmed to be > 16.6 ppm, the frequency monitors should be disabled so the input reference source is not automatically rejected as out of frequency range. Table 5. Input Reference Source Jitter Tolerance J i t t er To l e r a n c e Fr eq u en cy M on i t or A c c e p t an c e R an g e G.703 G.783 G.823 +/- 16.6 p p m GR-1244-CORE Fr eq u en cy A c c e p t an c e R an g e ( Pull-in) Fr eq u en cy A c c e p t an c e R an g e ( H o l d - i n ) Fr eq u en cy A c c e p t an c e R an g e ( P u l l - ou t ) +/- 4.6 p p m (see N ote 1) +/- 4.6 p p m (see N ote 1) +/- 4.6 p p m (see N ote 1) +/- 9.2 p p m (see N ote 2) +/- 9.2 p p m (see N ote 2) +/- 9.2 p p m (see N ote 2) Notes for Table 5. Note 1. The frequency acceptance and generation range will be +/-4.6 ppm around the required frequency when the external crystal frequency accuracy is within a tolerance of +/- 4.6 ppm. Note 2. The fundamental acceptance range and generation range is +/- 9.2 ppm with an exact external crystal frequency of 12.8 MHz. This is the default DPLL range, the range is also programmable from 0 to 80 ppm in 0.08 ppm steps. Revision 1.06/October 2002 Semtech Corp. 14 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 3. Minimum Input Jitter Tolerance (OC-3/STM-1) (for inputs supporting G.783 compliant sources) $ $ $ $ $ -LWWHUDQGZDQGHUIUHTXHQF\ORJVFDOH I I I I I I I I I Table 6. Amplitude and Frequency Values for Jitter Tolerance ST M l evel STM-1 P e ak t o p e ak am p l i t u d e ( u n i t I n t e r v al ) Fr eq u en cy ( H z ) A0 A1 A2 A3 A4 F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 2800 311 39 1.5 0.15 12u 178u 1.6m 15.6m 0.125 19.3 500 6.5k 65k 1.3m Output Clock Ports The device supports a set of main output clocks, TOUT0 and TOUT4, and a pair of secondary output clocks, 'Frame-Sync' and 'Multi-Frame-Sync'. The two main output clocks, T OUT0 and TOUT4, are independent of each other and are individually selectable. The two secondary output clocks, 'Frame-Sync' and 'Multi-Frame-Sync', are derived from TOUT0. The frequencies of the output clocks are selectable from a range of pre-defined spot frequencies and a variety of output technologies are supported, as defined in Table 8. Low-speed Output Clock (T OUT4) The TOUT4 clock is supplied on two output ports, TO8 and TO9. The former port will provide an AMI signal carrying a composite clock of 64 kHz and 8 kHz, according to ITU Recommendation Revision 1.06/October 2002 Semtech Corp. 15 G.703. The latter port will provide a TTL/CMOS signal at either 1.544 MHz or 2.048 MHz, depending on the setting of the SONSDHB pin. High-speed Output Clock (Part of T OUT0) The TOUT0 port has multiple outputs. Outputs TO1 and TO2 are TTL/CMOS output with a choice of 11 different frequencies up to 51.84 MHz. Outputs TO3 to TO5 are all TTL/CMOS outputs with fixed frequencies of 19.44 MHz, 38.88 MHz and 77.76 MHz respectively. Output TO6 is differential and can support clocks up to 155.52 MHz. Output T O7 is also differential and can support clocks up to 155.52 MHz. Each output is individually configured to operate at the frequencies shown in Table 8 (configuration must be consistent between ACS8510 devices for protection-switching to be effective - output clocks will be phase-aligned www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 4. Minimum Input Jitter Tolerance (DS1/E1) (for inputs supporting G.783 compliant sources) 3HDNWRSHDNMLWWHUDQGZDQGHUDPSOLWXGHORJ VFDOH $ $ -LWWHUDQGZDQGHUIUHTXHQF\ORJVFDOH I I I I Table 7. Amplitude and Frequency Values for Jitter Tolerance Ty p e S p e c. A mp litud e ( U I p k-p k) Fr e q u e n cy ( Hz ) A1 A2 F1 F2 F3 F4 DS1 G R - 1244- C O R E 5 0.1 10 500 8k 40k E1 I T U G . 823 1.5 0.2 20 2.4k 18k 100k between devices). Using the cnfg_differential_outputs register, outputs TO6 and T O7 can be made to be LVDS or PECL compatible. Frame Sync and Multi-Frame Sync Clocks (Part of T OUT0) Frame Sync (8 kHz) and Multi-Frame Sync (2 kHz) clocks are provided on outputs TO10 (FrSync) and TO11 (MFrSync). The FrSync and MFrSync clocks have a 50:50 mark space ratio. These are driven from the TOUT0 clock. They are synchronized with their counterparts in a second ACS8510 device (if used), using the technique described later. Revision 1.06/October 2002 Semtech Corp. 16 Low Jitter Multiple E1/DS1 Outputs This feature added to Rev2.1 is activated using the cnfg_control1 register. This sends a frequency of twice the Dig2 rate (see reg addr 39h, bits 7:6) to the APLL instead of the normal 77.76MHz. For this feature to be used, the Dig2 rate must only be set to 12352kHz/16384kHz using the cnfg_T0_output_frequencies register. The normal OC3 rate outputs are then replaced with E1/DS1 multiple rates. The E1(SONET)/ DS1(SDH) selection is made in the same way as for Dig2 using the cnfg_T0_output_enable register. Table 9 shows the relationship between primary output frequencies and the corresponding output in E1/DS1 mode, and which output they are available from. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Output Wander and Jitter Wander and jitter present on the output clocks are dependent on: 1. The magnitude of wander and jitter on the selected input reference clock (in Locked mode) 2. The internal wander and jitter transfer characteristic (in Locked mode) 3. The jitter on the local oscillator clock 4. The wander on the local oscillator clock (in Holdover mode) Wander and jitter are treated in different ways to reflect their differing impacts on network design. Jitter is always strongly attenuated, whilst wander attenuation can be varied to suit the application and operating state. Wander and jitter attenuation is performed using a digital phase locked loop (DPLL) with a programmable bandwidth. This gives a transfer characteristic of a low pass filter, with a programmable pole. It is sometimes necessary to change the filter dynamics to suit particular circumstances - one example being when locking to a new source, Table 8. Output Reference Source Selection Table P or t N am e O u t p u t P or t Te c h n o l o g y T01 TTL/CMOS 1.544 MHz/2.048 MHz, 3.088 MHz/4.096 MHz, 6.176 MHz/8.192 MHz, 6.48 MHz (default), 12.352 MHz/16.384 MHz, 19.44 MHz, 25.92 MHz T02 TTL/CMOS 1.544 MHz/2.048 MHz, 3.088 MHz/4.096 MHz, 6.176 MHz/8.192 MHz, 12.352 MHz/16.384 MHz, 25.92 MHz, 38.88 MHz (default), 51.84 MHz T03 TTL/CMOS 19.44 MHz - fixed T04 TTL/CMOS 38.88 MHz - fixed T05 TTL/CMOS 77.76 MHz - fixed T06 LVDS/PECL (LVDS default) 1.544 MHz/2.048 MHz, 3.088 MHz/4.096 MHz, 6.176 MHz/8.192 MHz, 12.352 MHz/16.384 MHz, 19.44 MHz, 38.88 MHz (default), 155.52 MHz, 311.04 MHz T07 PECL/LVDS (PECL default) 19.44 MHz (default), 51.84 MHz, 77.76 MHz, 155.52 MHz T08 A MI T09 TTL/CMOS 1.544 MHz/2.048 MHz T010 TTL/CMOS FrSync, 8 kHz - w ith a 50:50 MSR T011 TTL/CMOS MFrSync, 2 kHz - w ith a 50:50 MSR Fr eq u en ci es S u p p or t ed 64/8 kHz (comp osite clock, 64 kHz + 8 kHz) Note for Table 8. Where 1.544 MHz/2.048 MHz is shown, 1.544 MHz is SONET, and 2.048 MHz is SDH. Pin SONSDHB controls the default frequency output. Where the SONSDHB pin is High SONET is default, and when SONSDHB pin is Low SDH is default. Revision 1.06/October 2002 Semtech Corp. 17 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 9. Multiple E1/DS1 Ouputs in relation to Standard Outputs M od e Default Fr e q t o A PLL A PLL M u l t i p l i er 77.76 4 A PLL Fr e q cl k _ f i l t cl k _ f i l t /2 cl k _ f i l t /4 cl k _ f i l t /6 cl k _ f i l t /8 cl k _ f i l t / 12 cl k _ f i l t / 16 cl k _ f i l t / 48 DP L L Fr e q 311.04 311.04 155.52 77.76 51.84 38.88 25.92 19.44 6.48 77.76 n value 16 8 4 n x E1 32.768 4 131.072 131.072 65.536 32. 768 21.84533 16. 384 10.92267 8.192 2.730667 77.76 n x T1 24.704 4 98.816 49.408 24. 704 16.46933 12. 352 8.234667 6.176 2.058667 77.76 98.816 Freq uencies A vailab le b y Outp ut T01 T02 T03 T04 T05 T06 T06 T07 the filter can be opened up to reduce locking time and can then be gradually tightened again to remove wander. Since wander represents a relatively long-term deviation from the nominal operating frequency, it affects the rate of supply of data to the network element. Strong wander attenuation limits the rate of consumption of data to within a smaller range, so a larger buffer store is required to prevent data loss. But, since any buffer store potentially increases latency, wander may often only need to be removed at specific points within a network where buffer stores are acceptable, such as at digital cross connects. Otherwise, wander is sometimes not required to be attenuated and can be passed through transparently. The ACS8510 has programmable wander transfer characteristics in a range from 0.1 Hz to 20 Hz. The wander and jitter transfer characteristic is shown in Figure 5. Wander on the local oscillator clock will not have significant effect on the output clock whilst in Locked mode, so long as the DPLL bandwidth is set high enough so that the DPLL can compensate quickly enough for any frequency changes in the crystal. In Free-run or Holdover mode wander on the crystal is more significant. Revision 1.06/October 2002 Semtech Corp. 18 T06 T07 Variation in crystal temperature or supply voltage both cause drifts in operating frequency, as does ageing. These effects must be limited by careful selection of a suitable component for the local oscillator, as specified in the section Local Oscillator Clock. Phase Variation There will be a phase shift across the ACS8510 between the selected input reference source and the output clock. This phase shift may vary over time but will be constrained to lie within specified limits. The phase shift is characterised using two parameters, MTIE (Maximum Time Interval Error), and TDEV (Time Deviation), which, although being specified in all relevent specifications, differ in acceptable limits in each one. Typical measurements for the ACS8510 are shown in Figures 6 and 7, for Locked mode operation. Figure 8 shows a typical measurement of Phase Error accumulation in Holdover mode operation. The required performance for phase variation during Holdover is specified in several ways depending upon the particular circumstances pertaining: www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 5. Wander and Jitter Measured Transfer Characteristics % G Q L D * +] +] +] +] +] +] +] +] )UHTXHQF\+] 1. ETSI 300 462-5, Section 9.1, requires that the shortterm phase error during switchover (i.e., Locked to Holdover to Locked) be limited to an accumulation rate no greater than 0.05 ppm during a 15 second interval. 2. ETSI 300 462-5, Section 9.2, requires that the longterm phase error in the Holdover mode should not exceed 3. ANSI Tin1.101-1994, Section 8.2.2, requires that the phase variation be limited so that no more than 255 slips (of 125 µs each) occur during the first day of Holdover. This requires a frequency accuracy better than: ((24x60x60)+(255x125µs))/(24x60x60) = 0.37 ppm Temperature variation is not restricted, except to within the normal bounds of 0 to 50 °C. {(a1+a2)S+0.5bS2+c} 4. Telcordia GR.1244.CORE, Section 5.2., Table 4, shows that an initial frequency offset of 50 ppb is permitted on entering Holdover, whilst a drift over temperature of 280 ppb is allowed; an allowance of 40 ppb is permitted for all other effects. where a1 = 50 ns/s (allowance for initial frequency offset) a2 = 2000 ns/s (allowance for temperature variation) 5. ITU G.822, Section 2.6, requires that the slip rate during category(b) operation (interpreted as being applicable to Holdover mode operation) be limited to less than 30 slips (of 125 µs each) per hour b = 1.16x10-4 ns/s2 (allowance for ageing) c = 120 ns (allowance for entry into Holdover mode). ((((60 x 60)/30)+125µs)/(60x60)) = 1.042 ppm Revision 1.06/October 2002 Semtech Corp. 19 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 6. Maximum Time Interval Error of T OUT0 output port 1 00 G .8 13 o ption 1 , co nstan t te m pe rature w a nder lim it Tim e (n s) 10 1 M T IE m e as ure m en t o n 1 55 M H z ou tp ut, 1 9.44 M H z i/p (8 kH z locking), V e ctron 6 6 64 xtal 0.1 0 .01 0.01 0 .1 1 10 1 00 0 10 00 0 O b serva tio n interva l (s) 1 00 Figure 7. Time Deviation of T OUT0 output port 10 G .813 op tio n 1 con stan t tem perature w ander lim it T im e (ns ) 1 0.1 T D E V m ea su rem e nt on 1 55 M H z output, 1 9.4 4 M H z i/p (8kH z lock ing), V ectron 6 664 xtal 0 .01 0.01 0 .1 1 10 100 10 00 10 000 O b s erv ation in terv al (s) Figure 8. Phase error accumulation of T OUT0 output port in Holdover mode 10000000 Phase Error (ns) 1000000 P e rm itte d P h a s e E rr o r L im it 100000 10000 1000 100 Revision 1.06/October 2002 Semtech Corp. T y p ic a l m e a s u r e m e n t, 2 5 ° C c o n s ta n t te m p e r a tu re 10000 1000 20 100000 O b s e r v a tio n in te rv a l ( s ) www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Phase Build Out Phase Build Out (PBO) is the function to minimise phase transients on the output SEC clock during input reference switching. If the currently selected input reference clock source is lost (due to a short interruption, out of frequency detection, or complete loss of reference), the second, next highest priority reference source will be selected. During this transition, the Lost_Phase mode is entered. The typical phase disturbance on clock reference source switching will be less than 12 ns on the ACS8510. For clock reference switching caused by the main input failing or being disconnected, then the phase disturbance on the output will still be less than the 120 ns allowed for in the G.813 spec. The actual value is dependent on the frequency being locked to. ITU-T G.813 states that the max allowable short term phase transient response, resulting from a switch from one clock source to another, with Holdover mode entered in between, should be a maximum of 1 µs over a 15 second interval. The maximum phase transient or jump should be less than 120 ns at a rate of change of less than 7.5 ppm and the Holdover performance should be better than 0.05 ppm. On the ACS8510, PBO can be enabled, disabled or frozen using the µP interface. By default, it is enabled. When PBO is enabled, it can also be frozen, which will disable the PBO operation on the next input reference switch, but will remain with the current offset. If PBO is disabled while the device is in the Locked mode, there will be a phase jump on the output SEC clocks as the DPLL locks back to 0 degree phase error. Table 10. Microprocessor Interface Mode Selection UPSEL(2:0) Mode Description 111 110 101 100 011 010 001 000 OFF OFF SERIAL MOTOROLA INTEL MULTIPLEXED EPROM OFF Interface disabled Interface disabled Serial uP bus interface Motorola interface Intel compatible bus interface Multiplexed bus interface EPROM read mode Interface disabled (7) (6) (5) (4) (3) (2) (1) (0) Motorola Mode Parallel data + address: this mode is suitable for use with Motorola's 68x0 type bus. Intel Mode Parallel data + address: this mode is suitable for use with Intel's 80x86 type bus. Multiplexed Mode Data/address: this mode is suitable for use with microprocessors which share bus signals between address and data (e.g., Intel's 80x86 family). Serial Mode This mode is suitable for use with microprocessor which use a serial interface. EPROM Mode This mode is suitable for simple standalone applications where it is required to change the default loading of the register values to suit different applications. Microprocessor Interface This can be done by loading values from an external ROM. The data is read from the ROM automatically after power up when the UPSEL(2:0) pins are set to 001. Each register value is stored sequentially, with ROM address 0 corresponding to register address 0 and so on. The ACS8510 incorporates a microprocessor interface, which can be configured for the following modes via the bus interface mode control pins UPSEL(2:0) as defined in Table 10. The value in the chip_id location (address 00 & 01) is checked to see if it matches the ID number of the ACS8510 V2 (value 213E). Upon a successful number match, the remaining data Revision 1.06/October 2002 Semtech Corp. 21 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS from the ROM is used to set the internal register values. Only 64 locations in the ROM are required. Register Set All registers are 8-bits wide, organised with the most-significant bit positioned in the left-most bit, with bit significance decreasing towards the right most bit. Some registers carry several individual data fields of various sizes, from single-bit values (e.g. flags) upwards. Several data fields are spread across multiple registers; their organisation is shown in the register map, Table 11. Configuration Registers Each configuration register reverts to a default value on power-up or following a reset. Most default values are fixed, but some will be pinsettable. All configuration registers can be read out over the microprocessor port. Status Registers The Status Registers contain readable registers. They may all be read from outside the chip but are not writeable from outside the chip (except for a clearing operation). All status registers are read via shadow registers to avoid data hits due to dynamic operation. Each individual status register has a unique location. Register Access Most registers are of one of two types, configuration registers or status registers, the exceptions being the chip_ID and chip_revision registers. Configuration registers may be written to or read from at any time (the complete 8-bit register must be written, even if only one bit is being modified). All status registers may be read at any time and, in some status registers (such as the sts_interrupts register), any individual data field may be cleared by writing a 1 into each bit of the field (writing a 0 value into a bit will not affect the value of the bit). A description of each register is given in the Register Map, and Register Map Description. Revision 1.06/October 2002 Semtech Corp. 22 Interrupt Enable and Clear Interrupt requests are flagged on pin INTREQ (active High). Bits in the interrupt status register are set (high) by the following conditions: 1. Any reference source becoming valid or going invalid 2. A change in the operating state (eg. Locked, Holdover etc.) 3. A brief loss of the currently selected reference source 4. An AMI input error All interrupt sources are maskable via the mask register, each one being enabled by writing a '1' to the appropriate bit. Any unmasked bit set in the interrupt status register will cause the interrupt request pin to be asserted (high). All interrupts are cleared by writing a '1' to the bit(s) to be cleared in the status register. When all pending unmasked interrupts are cleared the interrupt pin will go inactive (low). The loss of the currently selected reference source will eventually cause the input to be considered invalid, triggering an interrupt. The time taken to raise this interrupt is dependant on the leaky bucket configuration of the activity monitors. The fastest leaky bucket setting will still take up to 128 ms to trigger the interrupt. The interrupt caused by the brief loss of the currently selected reference source is provided to facilitate very fast source failure detection if desired. It is triggered after missing just a couple of cycles of the reference source. Some applications require the facility to switch downstream devices based on the status of the reference sources. In order to provide extra flexibility, it is possible to flag the main reference failed interrupt (addr 06, bit 6) on the pin TDO. This is simply a copy of the status bit in the interrupt register and is independent of the mask register settings. The bit is reset by writing to the interrupt status register in the normal way. This feature can be enabled and disabled by writing to bit 6 of register 48Hex. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Register Map Shaded areas in the map are dont care and writing either 0 or 1 will not affect any function of the device. Bits labelled Set to 0 or Set to 1 must be set as stated during initialisation of the device, either following power up, or after a power on reset (POR). Failure to correctly set these bits may result in the device operating in an unexpected way. Some registers do not appear in this list. These are either not used, or have test functionality. Do not write to any undefined registers as this may cause the device to operate in a test mode. If an undefined register has been inadvertently addressed, the device should be reset to ensure the undefined registers are at default values. Table 11. Register Map A d d r. P ar am et er N am e ( Hex ) D at a B i t 7 ( m sb ) 00 6 5 4 chip _id (read only) chip _revision (read only) 03 cnfg_control1 (read /w rite) 04 cnfg_control2 (read /w rite) 05 sts_interrup ts (read /w rite) 06 08 sts_T4_inp uts (read /w rite) 09 sts_op erating_mod e (read only) 0A sts_p riority_tab le (read only) 0D 0F 0 ( l sb ) 8k Ed ge Polarity Set to '0' Set to '0' Set to '0' Set to '1' Set to '0' Ch ip revision numb er (7:0) Mu l t i p l e E1/T1 O/P A nalog d iv sync Set to '0' Phase loss flag limit <I_8> valid change <I_7> valid ch ange <I_6> valid change <I_5> valid ch ange <I_4> valid ch ange <I_3> valid ch ange <I_2> valid change <I_1> valid ch ange Op erating mode Main ref. failed <I_14> valid change <I_13> valid change <I_12> valid ch ange <I_11> valid ch ange <I_10> valid ch ange <I_9> valid change T4 ref failed A mi 2 V iolation A mi 2 L.O.S. A mi 1 V iolation A mi 1 L.O.S. Op erating mod e (2:0) High est p riority valid source Currently selected reference source 3rd high est p riority valid source 2nd high est p riority valid source sts_curr_inc_offset (read only) Current increment offset (7:0) Current increment offset (15:8) 07 0E 1 Device p ar t numb er (15:8) 02 0C 2 Device p ar t numb er (7:0) 01 0B 3 Current increment offset (18:16) sts_sources_valid (read only) <I_8> Revision 1.06/October 2002 Semtech Corp. <I_7> <I_6> <I_5> <I_4> <I_3> <I_2> <I_1> <I_14> <I_13> <I_12> <I_11> <I_10> <I_9> 23 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 11. Register Map (continued). A d d r. P ar am et er N am e ( Hex ) D at a B i t 7 ( m sb ) 10 sts_reference_sources (read /w rite) 6 5 4 3 2 1 status <I_2> status <I_1> 11 status <I_4> status <I_3> 12 status <I_6> status <I_5> 13 status <I_8> status <I_7> 14 status <I_10> status <I_9> 15 status <I_12> status <I_11> 16 status <I_14> status <I_13> p rogrammed _p riority <I_2> p rogrammed _p riority <I_1> 19 p rogrammed _p riority <I_4> p rogrammed _p riority <I_3> 1A p rogrammed _p riority <I_6> p rogrammed _p riority <I_5> 1B p rogrammed _p riority <I_8> p rogrammed _p riority <I_7> 1C p rogrammed _p riority <I_10> p rogrammed _p riority <I_9> 1D p rogrammed _p riority <I_12> p rogrammed _p riority <I_11> 1E p rogrammed _p riority <I_14> p rogrammed _p riority <I_13> 18 20 cnfg_ref_selection_p riority (read /w rite) cnfg_ref_source_freq uency (read /w rite) 0 ( l sb ) d ivn lock8k b ucket_id <I_1>(1:0) reference_source_freq uency <I_1>(3:0) 21 d ivn lock8k b ucket_id <I_2>(1:0) reference_source_freq uency <I_2>(3:0) 22 d ivn lock8k b ucket_id <I_3>(1:0) reference_source_freq uency <I_3>(3:0) 23 d ivn lock8k b ucket_id <I_4>(1:0) reference_source_freq uency <I_4>(3:0) 24 d ivn lock8k b ucket_id <I_5>(1:0) reference_source_freq uency <I_5>(3:0) 25 d ivn lock8k b ucket_id <I_6>(1:0) reference_source_freq uency <I_6>(3:0) 26 d ivn lock8k b ucket_id <I_7>(1:0) reference_source_freq uency <I_7>(3:0) 27 d ivn lock8k b ucket_id <I_8>(1:0) reference_source_freq uency <I_8>(3:0) 28 d ivn lock8k b ucket_id <I_9>(1:0) reference_source_freq uency <I_9>(3:0) 29 d ivn lock8k b ucket_id <I_10>(1:0) reference_source_freq uency <I_10>(3:0) 2A d ivn lock8k b ucket_id <I_11>(1:0) reference_source_freq uency <I_11>(3:0) 2B d ivn lock8k b ucket_id <I_12>(1:0) reference_source_freq uency <I_12>(3:0) 2C d ivn lock8k b ucket_id <I_13>(1:0) reference_source_freq uency <I_13>(3:0) 2D d ivn lock8k b ucket_id <I_14>(1:0) reference_source_freq uency <I_14>(3:0) Revision 1.06/October 2002 Semtech Corp. 24 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 11. Register Map (continued). A d d r. P ar am e t e r N am e ( Hex ) D at a B i t 7 ( m sb ) 30 31 6 5 4 cnfg_sts_remote_sources_ valid (read /w rite) 32 cnfg_op erating_mod e (read /w rite) 33 cnfg_ref_selection (read /w rite) 34 cnfg_mod e (read /w rite) 35 cnfg_T4 (read /w rite) 36 cnfg_d ifferential_inp uts (read /w rite) 37 cnfg_uPsel_p ins (read only) 38 cnfg_T0_outp ut_enab le (read /w rite) 39 cnfg_T0_outp ut_freq uencies (read /w rite) 3A cnfg_d ifferential_outp uts (read /w rite) 3B cnfg_b and w id th (read /w rite) 3C cnfg_nominal_freq uency (read /w rite) 1 Forced op erating mod e force_select_reference_source A u to external 2K enab le Ph ase alarm timeout enab le Clock ed ge Hold over Offset enab le Sq uelch Select T0/T1 SON ET/ SDH I/P External 2K Sync enab le Master/ Slave Force T1 inp ut source selection (only valid for inp uts I_5 to I_10) <I_6> PECL <I_5> PECL Micro-p rocessor typ e 311.04MHz on T06 1=SON ET 0=SDH for Dig2 1=SON ET 0=SDH for Dig1 T01 Digital2 Digital1 T07 Freq uency selection T06 Freq uency selection A uto b /w sw itch A cq /lock T03 19.44MHz T02 T04 38.88MHz T02 A cq uisition b and w id th T07 LV DS enab le T07 PECL enab le Set to '0' T05 77.76MHz T01 T06 LV DS enab le T06 PECL enab le N ormal/locked b and w id th N ominal freq uency (7:0) cnfg_h old over_offset (read /w rite) Hold over offset (7:0) Hold over offset (15:8) A u to Hold over A veraging Hold over offset (18:16) cnfg_freq _limit (read /w rite) DPLL Freq uency offset limit (7:0) DPLL Freq uency offset limit (9:8) 42 cnfg_interrup t_mask (read /w rite) 44 <I_8> valid ch ange <I_7> valid ch ange <I_6> valid ch ange <I_5> valid ch ange <I_4> valid ch ange <I_3> valid ch ange <I_2> valid ch ange <I_1> valid ch ange Op erating mod e Main ref. failed <I_14> valid ch ange <I_13> valid ch ange <I_12> valid ch ange <I_11> valid ch ange <I_10> valid ch ange <I_9> valid ch ange T4 ref A mi 2 V iolation A mi 2 L.O.S A mi 1 V iolation A mi 1 L.O.S 45 46 Reversion mod e N ominal freq uency (15:8) 40 43 0 ( l sb ) Remote status, ch annels <14:9> 3F 41 2 Remote status, ch annels <8:1> 3D 3E 3 cnfg_freq _d ivn (read /w rite) Divid e-inp ut-b y-n ratio (7:0) 47 Revision 1.06/October 2002 Semtech Corp. Divid e-inp ut-b y-n ratio (13:8) 25 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 11. Register Map (continued). A d d r. P ar am et er N am e ( Hex ) D at a B i t 7 ( m sb ) 6 5 4 3 2 Flag ref lost on TDO Ultra-fast sw itching External source sw itch enab le Freeze p hase b uildout Phase b uildout enab le 48 cnfg_monitors (read/w rite) 50 cnfg_activ_up p er_threshold0 (read/w rite) Configuration 0: Activity alarm set threshold (7:0) 51 cnfg_activ_low er_threshold0 (read/w rite) Configuration 0: Activity alarm reset threshold (7:0) 52 cnfg_b ucket_size0 (read/w rite) 53 cnfg_decay_rate0 (read/w rite) 54 cnfg_activ_up p er_threshold1 (read/w rite) Configuration 1: Activity alarm set threshold (7:0) 55 cnfg_activ_low er_threshold1 (read/w rite) Configuration 1: Activity alarm reset threshold (7:0) 56 cnfg_b ucket_size1 (read/w rite) 57 cnfg_decay_rate1 (read/w rite) 58 cnfg_activ_up p er_threshold2 (read/w rite) Configuration 2: Activity alarm set threshold (7:0) 59 cnfg_activ_low er_threshold2 (read/w rite) Configuration 2: Activity alarm reset threshold (7:0) 5A cnfg_b ucket_size2 (read/w rite) 5B cnfg_decay_rate2 (read/w rite) 5C cnfg_activ_up p er_threshold3 (read/w rite) Configuration 3: Activity alarm set threshold (7:0) 5D cnfg_activ_low er_threshold3 (read/w rite) Configuration 3: Activity alarm reset threshold (7:0) 5E cnfg_b ucket_size3 (read/w rite) 5F cnfg_decay_rate3 (read/w rite) 7F cnfg_uPsel (read/w rite) Revision 1.06/October 2002 Semtech Corp. 1 0 ( l sb ) Frequency monitors configuration (1:0) Configuration 0: Activity alarm b ucket size (7:0) Cfg 0:decay_rate (1:0) Configuration 1: Activity alarm b ucket size (7:0) Cfg 1:decay_rate (1:0) Configuration 2: Activity alarm b ucket size (7:0) Cfg 2:decay_rate (1:0) Configuration 3: Activity alarm b ucket size (7:0) Cfg 3:decay_rate (1:0) Micro-p rocessor typ e 26 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Register Map Description Table 12. Register Map Description Addr. Parameter N ame (H ex) chi p_i d 00 01 02 D escription D efault Value (bin) Thi s regi ster contai ns the chi p ID = 8510 (deci mal) Bi ts (7:0) C hi p ID bi ts (7:0) 00111110 Bi ts (7:0) C hi p ID bi ts (15:8) 00100001 chi p_revi si on Thi s read only regi ster contai ns the chi p revi si on number Thi s revi si on = 1 Last revi si on (engi neeri ng samples) = 0 cnfg_control1 Bi ts (7:6) 00000001 Unused Bit 5 =1 32/24MHz to APLL: Feeds 2x D i g2 frequency to the APLL i nstead of the normal 77.76Mhz. Thus the normal OC 3/STM1 outputs are replaced wi th multi ple E1/T1 rates. Note: D i g2 set bi ts (Reg. 39h Bi ts (7:6)) must be set to 11 for thi s mode. =0 77.76MHz to APLL Bit 4 =1 Synchroni zes the di vi ders i n the output APLL secti on to the di vi ders i n the D PLL secti on such that thei r phases ali gn. Thi s i s necessary i n order to have phase ali gnment between i nputs and output clocks at OC 3 deri ved rates (6.48 MHz to 77.76 MHz). Keepi ng thi s bi t hi gh may be necessary to avoi d the di vi ders getti ng out of synchroni zati on when qui ck changes i n frequency occur such as a force i nto Free-Run. =0 The di vi ders may get out of phase followi ng step changes i n frequency, but i n thi s mode the correct number of hi gh frequency edges i s guarenteed wi thi n any synchroni zati on peri od. The output wi ll frequency lock (default). The devi ce wi ll always remai n i n synchroni zati on 2 seconds from a reset, before the default setti ng appli es. 03 Bi ts 3 X X 000000 Test control - leave unchanged, or set to '0' Bit 2 =1 When i n 8k locki ng mode the system wi ll lock to the ri si ng i nput clock edge. =0 When i n 8k locki ng mode the system wi ll lock to the falli ng i nput clock edge. cnfg_control2 Bi ts (1:0) Test controls - leave unchanged, or set to '00' Bi ts (7:6) Unused Bi ts (5:3) defi ne the phase loss flag li mi t. By default set to 4 (100) whi ch corresponds to approxi mately 140°. A lower value sets a correspondi ng lower phase li mi t. The flag li mi t determi nes the value at whi ch the D PLL i ndi cates phase lost as a result of i nput ji tter, a phase jump, or a frequency jump on the i nput 04 Bi ts (2:0) sts_i nterrupts X X 100010 Test controls - leave unchanged, or set to '010' Thi s regi ster contai ns one bi t for each bi t of sts_sources_vali d, one for loss of reference the devi ce was locked to, and another for the operati ng mode. All bi ts are acti ve hi gh. All bi ts except the mai n_ref_fai led bi t (bi t 14) are set on a 'change' i n the state of the relevent status bi t, i .e. i f a source becomes vali d, or goes i nvali d i t wi ll tri gger an i nterrupt. If the Operati ng Mode (regi ster 9) changes state the i nterrupt wi ll be generated. Bi t 14 (mai n_ref_fai led) of the i nterrupt status regi ster i s used to flag i nacti vi ty on the reference that the devi ce i s locked to more qui ckly than the acti vi ty moni tors can support. If bi t 6 of the cnfg_moni tors regi ster (flag ref loss on TD O) i s set, then the state of thi s bi t i s dri ven onto the TD O pi n of the devi ce. All bi ts are maskable by the bi ts i n the cnfg_i nterrupt_mask regi ster. Each bi t may be cleared i ndi vi dually by wri ti ng a '1' to that bi t, thus resetti ng the i nterrupt. Any number of bi ts can be cleared wi th a si ngle wri te operati on. Wri ti ng '0's wi ll have no effect. 05 Bi ts (7:0) <I_8> to <I_1> 00000000 06 Bi ts (7:0) Operati ng mode, mai n ref fai led, <I_14> to <I_9> 00000000 Revision 1.06/October 2002 Semtech Corp. 27 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) D escription sts_T4_i nputs Thi s regi ster holds the status flags of the AMI i nputs and the TOUT4 reference. The alarms once set wi ll hold thei r state unti l reset. Each bi t may be cleared i ndi vi dually by wri ti ng a '1' to that bi t, thus resetti ng the i nterrupt. Wri ti ng '0's wi ll have no effect. These bi ts can also generate i nterrupts. Bi ts (7:5) Bit 4 =1 =0 Bit 3 =1 =0 Bit 2 =1 =0 Bit 1 =1 =0 Bit 0 =1 =0 08 sts_operati ng_mode 09 sts_pri ori ty_table D efault Value (bin) Unused. T4 reference fai led - no vali d TIN1 i nput (<I_10>:<I_5>), T4 D PLL cannot lock to source (default) T4 reference good - vali d TIN1 i nput avai lable. X X X 10000 Ami 2 Vi olati on detected Ami 2 clear (default) Ami 2 Loss of si gnal Ami 2 clear (default) Ami 1 Vi olati on detected Ami 1 clear (default) Ami 1 Loss of si gnal Ami 1 clear (default) Thi s read-only regi ster holds the current operati ng state of the mai n state machi ne. Fi gure 11 shows how the values of the 'operati ng state' vari able match wi th the i ndi vi dual states. Bi ts (7:3) Unused. Bi ts (2:0) 001 010 100 110 101 111 State Free-Run (default) Holdover Locked Pre-locked Pre-locked2 Phase lost X X X X X 001 Thi s i s a 16-bi t read-only regi ster. Bi ts (15:12) Thi rd hi ghest pri ori ty vali d source: thi s i s the channel number of the i nput reference source whi ch i s vali d and has the next-hi ghest pri ori ty to the second-hi ghest-pri ori ty vali d source. Bi ts (11:8) Second hi ghest pri ori ty vali d source: thi s i s the channel number of the i nput reference source whi ch i s vali d and has the next-hi ghest pri ori ty to the hi ghest-pri ori ty vali d source. Bi ts (7:4) Hi ghest pri ori ty vali d source: thi s i s the channel number of the i nput reference source whi ch i s vali d and has the hi ghest pri ori ty - i t may not be the same as the currently selected reference source (due to fai lure hi story or changes i n programmed pri ori ty). Bi ts (3:0) C urrently selected reference source: thi s i s the channel number of the i nput reference source whi ch i s currently i nput to D PLL. Note that these regi sters are updated by the state machi ne i n response to the contents of the cnfg_ref_selecti on_pri ori ty regi ster and the ongoi ng status of i ndi vi dual channels; channel number '0000', appeari ng i n any of these regi sters, i ndi cates that no channel i s avai lable for that pri ori ty. 0A Bi ts (7:4) Bi ts (3:0) Hi ghest pri ori ty vali d source (sts_pri ori ty_table bi ts (7:4)) C urrently selected reference source (sts_pri ori ty_table bi ts (3:0)) 00000000 0B Bi ts (7:4) Bi ts (3:0) 3 rd-hi ghest pri ori ty vali d source (sts_pri ori ty_table bi ts (15:12)) 2nd-hi ghest pri ori ty vali d source (sts_pri ori ty_table bi ts (11:8)) 00000000 Revision 1.06/October 2002 Semtech Corp. 28 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) sts_curr_i nc_offset D escription D efault Value (bin) Thi s read-only regi ster contai ns a si gned-i nteger value representi ng the 19 si gni fi cant bi ts of the current i ncrement offset of the di gi tal PLL. The regi ster may be read peri odi cally to bui ld up a hi stori cal database for later use duri ng holdover peri ods (thi s would only be necessary i f an external osci llator whi ch di d not meet the stabi li ty cri teri a descri bed i n Local Osci llator C lock secti on i s used). The regi ster wi ll read 00000000 i mmedi ately after reset. 0C Bi ts (7:0) sts_curr_i nc_offset bi ts (7:0) 00000000 0D Bi ts (7:0) sts_curr_i nc_offset bi ts (15:8) 00000000 07 Bi ts (7:3) Bi ts (2:0) Unused sts_curr_i nc_offset bi ts (18:16) X X X X X 000 sts_sources_vali d Thi s regi ster contai ns a bi t to show vali di ty for every reference source. =1 Vali d source =0 Invali d source (default) 0E Bi ts (7:0) <I_8> to <I_1> 00000000 0F Bi ts (7:6) Bi ts (5:0) Unused <I_14> to <I_9> X X 000000 sts_reference_sources Thi s i s a 7-byte regi ster whi ch holds the status of each of the 14 i nput reference sources. The status of each reference source i s shown i n a 4-bi t fi eld. Each bi t i s acti ve hi gh.To ai d status checki ng, a copy of each status bi t 3 i s provi ded i n the sts_sources_vali d regi ster. The status i s reported as follows: (Each bi t may be cleared i ndi vi dually) Status Status Status Status bi t 3 bi t 2 bi t 1 bi t 0 = Source vali d (no alarms) (bi t 3 i s combi nati on of bi ts (2:0)) (default 0) = out-of-band alarm (default 1) = no acti vi ty alarm (default 1) = phase lock alarm (default 0) 10 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_2> Status of i nput reference source <I_1> 01100110 11 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_4> Status of i nput reference source <I_3> 01100110 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_6> Status of i nput reference source <I_5> 01100110 13 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_8> Status of i nput reference source <I_7> 01100110 14 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_10> Status of i nput reference source <I_9> 01100110 15 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_12> Status of i nput reference source <I_11> 01100110 16 Bi ts (7:4) Bi ts (3:0) Status of i nput reference source <I_14> Status of i nput reference source <I_13> 01100110 12 sts_reference_sources (conti nued) cnfg_ref_selecti on_pri ori ty Thi s regi ster holds the pri ori ty of each of the 14 i nput reference sources. The pri ori ty values are all relati ve to each other, wi th lower-valued numbers taki ng hi gher pri ori ti es. Only the values '1' to '15' (dec) are vali d - '0' di sables the reference source. Each reference source should be gi ven a uni que number, however two sources gi ven the same pri ori ty number wi ll be assi gned on a fi rst i n fi rst out basi s. It i s recommended to reserve the pri ori ty value '1' as thi s i s used when forci ng reference selecti on vi a the cnfg_ref_selecti on regi ster. If the user does not i ntend to use the cnfg_ref_selecti on regi ster then the pri ori ty value '1' need not be reserved. 18 19 1A 1B Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_2> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_1> Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_4> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_3> Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_6> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_5> Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_8> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_7> Revision 1.06/October 2002 Semtech Corp. 29 00110010 01010100 01110110 10011000 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) 1C cnfg_ref_selecti on_pri ori ty (conti nued) 1D 1E cnfg_ref_source_frequency D escription Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_10> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_9> Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_12> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_11> Bi ts (7:4) Programmed pri ori ty of i nput reference source <I_14> Bi ts (3:0) Programmed pri ori ty of i nput reference source <I_13> D efault Value (bin) 10111010 11010001 (MSTSLVB=0) 11011100 (MSTSLVB=1) 11111110 Thi s regi ster i s used to set up each of the 14 i nput reference sources. Bi ts (7:6) of each byte defi nes the operati on undertaken on the i nput frequency, i n accordance wi th the followi ng key: 00 01 10 11 The i nput frequency i s fed di rectly i nto the D PLL. (default). The i nput frequency i s i nternally di vi ded down to 8 kHz, before bei ng fed i nto the D PLL. (For hi gh ji tter tolerance). Unsupported confi gurati on - do not use. Uses the di vi si on coeffi ci ent stored i n regi sters 46 and 47 (cnfg_freq_di vn) to di vi de the i nput by thi s value pri or to bei ng fed i nto the D PLL. The frequency moni tors must be di sabled. The di vi ded down frequency should equal 8 kHz. The frequency (3:0) should be set to the nearest spot frequency just below the actual i nput frequency. The D i vN feature works for i nput frequenci es between 1.544 MHz and 100 MHz. Bi ts (5:4) defi ne whi ch leaky bucket group (0-3) i s used, as defi ned i n regi sters 50 to 5F. (default 00). Bi ts (3:0) defi nes the frequency of the reference source i n accordance wi th the followi ng: 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 8 kHz (fi xed <I_1>, <I_2>, default <I_3>, <I_4>) 1.544 MHz (SONET)/2.048 MHz (SD H) (as defi ned by regi ster 34, bi t 2) (default <I_12>, <I_13>, <I_14>) 6.48 MHz (default <I_11> when MSTSLVB = 1) 19.44 MHz (default <I_11> when MSTSLVB=0, and <I_5>, <I_6>, <I_7>, <I_8>, <I_9>, <I_10>) 25.92 MHz 38.88 MHz 51.84 MHz 77.76 MHz 155.52 MHz 2 kHz 4 kHz 20 Frequency of reference source <I_1> - fi xed at 00000000 for 8kHz only 00000000 21 Frequency of reference source <I_2> - fi xed at 00000000 for 8kHz only 00000000 22 Frequency of reference source <I_3> 00000000 23 Frequency of reference source <I_4> 00000000 24 Frequency of reference source <I_5> 00000011 25 Frequency of reference source <I_6> 00000011 26 Frequency of reference source <I_7> 00000011 27 Frequency of reference source <I_8> 00000011 28 Frequency of reference source <I_9> 00000011 29 Frequency of reference source <I_10> 00000011 Frequency of reference source <I_11> 00000010 (MSTSLVB=0) 00000011 (MSTSLVB=1) 2A Revision 1.06/October 2002 Semtech Corp. 30 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) 2B cnfg_ref_source_frequency (conti nued) D escription D efault Value (bin) Frequency of reference source <I_12> 00000001 2C Frequency of reference source <I_13> 00000001 2D Frequency of reference source <I_14> 00000001 cnfg_sts_remote_sources_ vali d Thi s regi ster holds the status of the reference sources suppli ed to the other devi ce i n a master/slave confi gurati on. It i s a copy of the other devi ce's sts_sources_vali d regi ster. The regi ster i s part of the protecti on mechani sm. 30 Bi ts (7:0) Reference sources <I_8>:<I_1> 11111111 31 Bi ts (7:6) Bi ts (5:0) Unused Reference sources <I_14>:<I_9> XX111111 cnfg_operati ng_mode 32 Thi s regi ster i s used to force the devi ce i nto a desi red operati ng state, represented by the bi nary values shown i n Fi gure 11. Value 0 (hex) allows the control state machi ne to operate automati cally. Bi ts (7:3) Bi ts (2:0) cnfg_ref_selecti on 33 cnfg_mode X X X X X 000 Unused D esi red operati ng state (as per Fi gure 11) Thi s regi ster i s used to force the devi ce to select a parti cular i nput reference source, i rrespecti ve of i ts pri ori ty. Wri ti ng to thi s regi ster temporari ly rai ses the selected i nput to pri ori ty '1'. Provi ded no other i nput i s already programmed wi th pri ori ty '1', and reverti ve mode i s on, thi s source wi ll be selected. Bi ts (7:4) Unused Bi ts (3:0) allows D esi red reference source (0000 and 1111 di sables the force selecti on, and automati c selecti on of all sources, default i s 1111) XXXX1111 Thi s regi ster contai ns several i ndi vi dual confi gurati on fi elds, as detai led below: Bit 7 =1 Auto 2 kHz Sync enable: External 2 kHz Sync wi ll be enabled only when the source i s locked to 6.48 MHz. Otherwi se i t wi ll be di sabled (default) =0 Auto 2 kHz Sync di sable: The user controls thi s functi on usi ng bi t 3 of thi s regi ster, as descri bed below Bit 6 =1 Phase Alarm Ti meout enable: The phase alarm wi ll ti meout after 100 seconds (default) =0 Phase Alarm Ti meout di sable: The phase alarm wi ll not ti meout and must be reset by software 34 Bit 5 =1 Ri si ng C lock Edge selected: The devi ce wi ll reference to the ri si ng edge of the external 12.8 MHz crystal osci llator si gnal =0 Falli ng edge Edge selected: The devi ce wi ll reference to the falli ng edge of the external 12.8 MHz crystal osci llator si gnal (default) Bit 4 =1 Holdover offset enable: The devi ce wi ll adopt the Holdover offset value stored i n the cnfg_holdover_offset regi ster, i n order to set the frequency i n Holdover =0 Holdover offset di sable: The devi ce wi ll i gnore the value and Holdover wi ll freeze the frequency of the D PLL on enteri ng Holdover mode (default) 11001000 (MSTSLVB=0) (SONSD HB=0) 11001100 (MSTSLVB=0) (SONSD HB=1) 11000010 (MSTSLVB=1) (SONSD HB=0) 11000110 (MSTSLVB=1) (SONSD HB=1) Bit 3 = 1 External 2 kHz Sync Enable: The devi ce wi ll ali gn the phase of i ts i nternally generated Frame Sync si gnal (8 kHz) and Multi -Frame Sync si gnal (2 kHz) wi th that of the si gnal suppli ed to the Sync2K pi n. The devi ce should be locked to a 6.48 MHz output from another A C S 8510. = 0 External 2 kHz Sync D i sable: The devi ce wi ll i gnore the Sync2k pi n. Revision 1.06/October 2002 Semtech Corp. 31 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) cnfg_mode (conti nued) D escription D efault Value (bin) Thi s regi ster contai ns several i ndi vi dual confi gurati on fi elds, as detai led below: Bit 2 = 1 SONET Mode: The devi ce expects the i nput frequency of any i nput channel gi ven the value '0001' i n the cnfg_ref_source_frequency regi ster to be 1544 kHz = 0 SD H Mode: The devi ce expects the i nput frequency of any i nput channel gi ven the value '0001' i n the cnfg_ref_source_frequency regi ster to be 2048 kHz. At start up or reset the bi t value wi ll be defaulted to the setti ng of pi n SONSD HB. Thi s setti ng can subsequently be altered by changi ng thi s bi t value 11001000 (MSTSLVB=0) (SONSD HB=0) 11001100 (MSTSLVB=0) (SONSD HB=1) Bit 1 = 1 Master Mode: The devi ce wi ll adopt the master mode and make the acti ve deci si ons of 11000010 whi ch source to select, etc. Thi s bi t i s wri teable, but i ts default value i s determi ned by the pi n, (MSTSLVB=1) MSTSLVB (SONSD HB=0) = 0 Slave Mode: The devi ce wi ll adopt the slave mode and wi ll follow the master devi ce. At start up or reset the bi t value wi ll be defaulted to the setti ng of pi n MSTSLVB. Thi s setti ng 11000110 can subsequently be altered by changi ng thi s bi t value (MSTSLVB=1) (SONSD HB=1) Bit 0 = 1 Reverti ve Mode: The devi ce wi ll swi tch to the hi ghest pri ori ty source avai lable shown i n the sts_pri ori ty_table regi ster, bi ts (7:4) = 0 Non Reverti ve Mode: The devi ce wi ll retai n the presently selected source (default) 34 cnfg_T4 35 Thi s controls D PLL _T4 (output on TO8/TO9) and i nput source selecti on: Bi ts (7:6) Unused Bit 5 =1 =0 D PLL_T4 i s turned off (squelched) D PLL_T4 i s on (default) Bit 4 =1 =0 Selects whi ch D PLL (T4 or T0) source feeds outputs TO8/TO9: D PLL_T0 output i s fed to outputs TO8 and TO9 D PLL_T4 output i s fed to outputs TO8 and TO9 X X 000000 Bi ts (3:0) Input source selecti on. The devi ce wi ll swi tch to the source shown i n thi s fi eld for the generati on of the TOUT4 si gnal. If '0' i t wi ll select the hi ghest pri ori ty acti ve TIN1. cnfg_di fferenti al_i nputs 36 cnfg_uPsel_pi ns 37 Thi s regi ster contai ns two i ndi vi dual confi gurati on fi elds, as follows: Bi ts (7:2) Unused Bit 1 =1 =0 Input <I_6> i s PEC L-compati ble (D efault) Input <I_6> i s LVD S-compati ble Bit 0 =1 =0 Input <I_5> i s PEC L-compati ble Input <I_5> i s LVD S-compati ble (D efault) X X X X X X 10 Thi s read only regi ster returns a value i ndi cati ng the mi croprocessor type selected at power up or reset. Thi s i s set by the confi gurati on of the UPSEL pi ns (pi ns 58 - 60). If the UPSEL pi n confi gurati on i s changed whi le the devi ce i s operati ng no effect wi ll take place, but thi s regi ster wi ll reflect that change, so i ndi cati ng the confi gurati on that wi ll be i mplemented at the next power up or reset. The mi croprocessor type can be changed wi th the devi ce operati onal, though regi ster 7F. Bi ts (7:3) Unused. Bi t (2:0) 000 001 010 011 100 101 110 111 Mi croprocessor type OFF (i nterface di sabled) EPROM MULTIPLEXED INTEL MOTOROLA SERIAL OFF (i nterface di sabled) OFF (i nterface di sabled) Revision 1.06/October 2002 Semtech Corp. 32 Bi ts(7:3)= XXXXX Bi ts(2:0)= UPSEL pi n confi gurati on www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) cnfg_T0_output_enable D escription Thi s regi ster contai ns several i ndi vi dual confi gurati on fi elds, as follows: Bit 7 =1 =0 Bit 6 =1 =0 Bit 5 =1 =0 Bit 4 =1 =0 38 D efault Value (bin) Bit 3 =1 =0 T06 output frequency set to 311.04 MHz * T06 output frequency set by Address 3A (5:4) (default) SONET mode selected for D i g2 SD H mode selected for D i g2 (default) - see regi ster cnfg_T0_output_frequenci es SONET mode selected for D i g1 SD H mode selected for D i g1 (default) - see regi ster cnfg_T0_output_frequenci es Output port T01 enabled (default) Output port T01 di sabled** - see regi ster cnfg_T0_output_frequenci es 00011111 Output port T02 enabled (default) Output port T02 di sabled** - see regi ster cnfg_T0_output_frequenci es Bit 2 =1 =0 Output port T03 enabled (19.44 MHz*) (default) Output port T03 di sabled** Bit 1 =1 =0 Output port T04 enabled (38.88 MHz*) (default) Output port T04 di sabled** Bit 0 =1 =0 Output port T05 enabled (77.76 MHz*) (default) Output port T05 di sabled** Notes: * D efaults frequenci es are changed to multi ples of E1/T1 i f the appropri ate bi t of the cnfg_control 1 regi ster i s set to 1. For detai ls, see Table 8. ** "D i sabled" means that the output port holds a stati c logi c value (the port i s not Tri -stated). cnfg_T0_output_frequenci es 39 Thi s regi ster holds the frequency selecti ons for each output port, as detai led below.* Bi ts (7:6) 00 01 10 11 D i g2 1544 kHz/2048 kHz (default) 3088 kHz/4096 kHz 6176 kHz/8192 kHz 12352 kHz/16384 kHz Bi ts (5:4) 00 01 10 11 D i g1 1544 kHz/2048 kHz (default) 3088 kHz/4096 kHz 6176 kHz/8192 kHz 12352 kHz/16384 kHz Bi ts (3:2) 00 01 10 11 T02 25.92 MHz 51.84 MHz 38.88 MHz (default) D i g2 Bi ts (1:0) 00 01 10 11 T01 6.48 MHz (default) 25.92 MHz 19.44 MHz D i g1 00001000 For D i g1/D i g2 the frequency values are shown for SONET/SD H. They are selected vi a the SONET/SD H bi ts i n regi ster cnfg_T0_output_enable. Note: * The above frequenci es are changed to multi ples of E1/T1 i f the appropri ate bi t of the cnfg_control 1 regi ster i s set to 1. For detai ls, see Table 8. Revision 1.06/October 2002 Semtech Corp. 33 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) cnfg_di fferenti al_outputs 3A cnfg_bandwi dth 3B cnfg_nomi nal_frequency D escription D efault Value (bin) Thi s regi ster holds the frequency selecti ons and the port-technology type for the di fferenti al outputs, T06 and T07, as detai led below. Bi ts (7:6) 00 01 10 11 T07 155.52 MHz 51.84 MHz 77.76 MHz 19.44 MHz (default) Bi ts (5:4) 00 01 10 11 T06 38.88 MHz (default) 19.44 MHz 155.52 MHz D i g1 Bi ts (3:2) 00 01 10 11 T07 Port di sabled PEC L-compati ble (default) LVD S-compati ble Unused (1:0) 00 01 10 11 T06 Port di sabled PEC L-compati ble LVD S-compati ble (default) Unused 11000110 Thi s regi ster contai ns i nformati on used to control the operati on of the di gi tal PLL. When bandwi dth selecti on i s set to automati c, the D PLL wi ll use the acqui si ti on bandwi dth setti ng when out of lock, and the normal/locked bandwi dth setti ng when i n lock. When set to manual, the D PLL wi ll alway use the normal/locked bandwi dth setti ng. Bit 7 =1 =0 Automati c operati on Manual operati on (default) Bi ts (6:4) 000 001 010 011 100 101 110 111 Acqui si ti on bandwi dth 0.1 Hz 0.3 Hz 0.5Hz 1.0 Hz 2.0 Hz 4.0 Hz 8.0 Hz 17 Hz (default) Bit 3 Unused Bi t (2:0) 000 001 010 011 100 101 110 111 Loop bandwi dth 0.1 Hz 0.3 Hz 0.5 Hz 1.0 Hz 2.0 Hz 4.0 Hz (default) 8.0 Hz 17 Hz 0111X101 Thi s regi ster holds a 16 bi t unsi gned i nteger allowi ng compensati on for offset of the crystal osci llator from the nomi nal 12.8 MHz. See secti on C rystal Frequency C ali brati on. D efault results i n 0 ppm adjustment. 3C Bi ts (7:0) cnfg_nomi nal_frequency bi ts (7:0) 10011001 3D Bi ts (7:0) cnfg_nomi nal_frequency bi ts (15:8) 10011001 cnfg_holdover_offset Thi s regi ster holds a 19 bi t si gned i nteger, representi ng the holdover offset value, whi ch can be used to set the holdover mode frequency when enabled vi a the holdover offset enabled bi t i n the cnfg_mode regi ster. 3E Bi ts (7:0) cnfg_holdover_offset bi ts (7:0) 00000000 3F Bi ts (7:0) cnfg_holdover_offset bi ts (15:8) 00000000 Bit 7 =1 Auto Holdover Averagi ng enable. Thi s enables the frequency average to be taken from 32 samples. One sample taken every 32 seconds, after the frequency has been confi rmed to be i n-band by the frequency moni tors. Thi s gi ves a 17 mi nute hi story of the currently locked to reference source for use i n Holdover. (default). =0 Auto Holdover Averagi ng di sabled. 40 cnfg_freq_li mi t Bi ts (6:3) Unused Bi ts (2:0) cnfg_holdover_offset bi ts (18:16) 1X X X X 000 Thi s regi ster holds a 10 bi t unsi gned i nteger representi ng the pull-i n range of the D PLL. It should be set accordi ng to the accuracy of crystal i mplemented i n the appli cati on, usi ng the followi ng formula: Frequency range +/- (ppm) = (cnfg_freq_li mi t x 0.0785)+0.01647 or cnfg_freq_li mi t = (Frequency range +/- (ppm) - 0.01647) / 0.0785 D efault value when SRC SW i s left unconnected or ti ed low i s ±9.3 ppm. D efault value when SRC SW i s hi gh i s the full range of around ±80 ppm. Revision 1.06/October 2002 Semtech Corp. 34 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) 41 cnfg_freq_li mi t (conti nued) 42 cnfg_i nterrupt-mask D escription Bi ts (7:0) cnfg_freq_li mi t bi ts (7:0) Bi ts (7:2) Unused Bi ts (1:0) cnfg_freq_li mi t bi ts (9:8) D efault Value (bin) 01110101 (SRC SW low) 11111111 (SRC SW hi gh) X X X X X X 00 (SRC SW low) XXXXXX11 (SRC SW hi gh) Each bi t, i f set to '0' wi ll di sable the appropri ate i nterrupt source i n ei ther the i nterrupt status regi ster or the sts_T4_i nputs regi ster. 43 Bi ts (7:0) cnfg_i nterrupt_mask bi ts (7:0) 11111111 44 Bi ts (7:0) cnfg_i nterrupt_mask bi ts (15:8) 11111111 45 Bi ts (7:5) Bi ts (4:0) Unused cnfg_i nterrupt_mask bi ts (20:16) XXX11111 cnfg_freq_di vn Thi s 14 bi t i nteger i s used as the di vi sor for any i nput appli ed to <I_14>:<I_1> to get the phase locki ng frequency desi red. Only acti ve for i nputs wi th the D i vN bi t set to 1 . Thi s wi ll cause the i nput frequency to be di vi ded by (N+1) pri or to phase compari son, e.g. program N to: ((i nput freq)/ 8 kHz) -1 The reference_source_frequency bi ts should be set to reflect the closest spot frequency to the i nput frequency, but must be lower than the i nput frequency. 46 Bi ts (7:0) cnfg_freq_di vn bi ts (7:0) 00000000 47 Bi ts (7:6) Bi ts (5:0) Unused cnfg_freq_di vn bi ts (13:8) X X 000000 cnfg_moni tors Thi s 7 bi t regi ster allows global confi gurati on of moni tors and control of phase bui ld out. Bi t 7 Unused Bit 6 =1 Enables value of the mai n_ref_fai led i nterrupt to be dri ven out of pi n TD O =0 D i sables value of the mai n_ref_fai led i nterrupt from bei ng dri ven out of pi n TD O (default) Bit 5 =1 Enables ultra fast swi tchi ng: Allows the D PLLto rai se an i nacti vi ty alarm on the currently selected source after mi ssi ng only a few cycles. See secti on on Ultra Fast Swi tchi ng =0 Normal operati on (default) 48 Bit 4 =1 Forces locki ng to <I_3> i f pi n SRC SW hi gh, or <I_4> i f SRC SW low =0 Pi n SRC SW i gnored , and automati c control enabled X 0000101 (SRC SW low) X 0010101 (SRC SW hi gh) Bit 3 =1 Wi ll freeze the output phase relati onshi p wi th the current i nput to output phase offset =0 Allows changes i n i nput to output phase offset (Normal phasebui ld out mode) (default) Bit 2 =1 Enables phase bui ld out (default) =0 D PLL wi ll always lock to 0° Bi ts (1:0) are for confi guri ng frequency moni tors- 00 = off, 01 = 15 ppm (default), others are reserved for future use. 50 cnfg_acti v_upper_threshold0 Bi ts (7:0) set the value i n the leaky bucket that causes the acti vi ty alarm to be rai sed 00000110 51 cnfg_acti v_lower_threshold0 Bi ts (7:0) set the value i n the leaky bucket that causes the acti vi ty alarm to be cleared 00000100 cnfg_bucket_si ze0 Bi ts (7:0) set the maxi mum value that the leaky bucket can reach gi ven an i nacti ve i nput 00001000 cnfg_decay_rate0 Bi ts (7:2) 52 53 Unused Bi ts (1:0) control the leak rate of the leaky bucket. The fi ll-rate of the bucket i s +1 for every 128 ms i nterval that has experi enced some level of i nacti vi ty. The decay rate i s programmable i n rati os of the fi ll rate. The rati o can be set to 1:1, 2:1, 4:1, 8:1 by usi ng values of 00, 01, 10, 11 respecti vely. However, these buckets are not true leaky buckets i n nature. The bucket stops leaki ng when i t i s bei ng fi lled. Thi s means that the fi ll and decay rates can be the same (00 = 1:1) wi th the net effect that an acti ve i nput can be recogni sed at the same rate as an i nacti ve one. Revision 1.06/October 2002 Semtech Corp. 35 X X X X X X 01 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 12. Register Map Description (continued). Addr. Parameter N ame (H ex) D escription D efault Value (bin) 54 cnfg_acti v_upper_threshold1 As for regi ster 50 but for bucket 1 00000110 55 cnfg_acti v_lower_threshold1 00000100 As for regi ster 51 but for bucket 1 56 cnfg_bucket_si ze1 As for regi ster 52 but for bucket 1 00001000 57 cnfg_decay_rate1 As for regi ster 53 but for bucket 1 X X X X X X 01 58 cnfg_acti v_upper_threshold2 As for regi ster 50 but for bucket 2 00000110 59 cnfg_acti v_lower_threshold2 00000100 As for regi ster 51 but for bucket 2 5A cnfg_bucket_si ze2 As for regi ster 52 but for bucket 2 00001000 5B cnfg_decay_rate2 As for regi ster 53 but for bucket 2 X X X X X X 01 5C cnfg_acti v_upper_threshold3 As for regi ster 50 but for bucket 3 00000110 5D cnfg_acti v_lower_threshold3 00000100 As for regi ster 51 but for bucket 3 5E cnfg_bucket_si ze3 As for regi ster 52 but for bucket 3 00001000 5F cnfg_decay_rate3 As for regi ster 53 but for bucket 3 X X X X X X 01 cnfg_uPsel Bi ts (7:3) 7F Unused Bi ts (2:0) can be used to change the mode of the mi croprocessor i nterface. The i nterface wi ll i ni ti ally be set as the pi ns UPSEL (pi ns 58 - 60) - the pi n set up can be read vi a regi ster 37 (cnfg_uPsel_pi ns). At power up or reset the devi ce wi ll default to thi s setti ng. Thi s regi ster can be used to change the mi croprocessor mode after start up, supporti ng booti ng from EPROM and subsequently communi cati ng vi a another mode. At start up the EPROM wi ll down load the pre-programmed setti ngs for all the regi sters, and as the last operati on, acti on the change of i nterface wi th thi s last regi ster. It i s recommended that thi s functi on i s only used for EPROM start up appli cati ons, as subsequent versi ons of thi s devi ce may only allow operati on i n thi s way. The bi ts are defi ned i n Table 9 or as gi ven i n regi ster 37 of the regi ster map descri pti on. Selection of Input Reference Clock Source Under normal operation, the input reference sources are selected automatically by an order of priority. But, for special circumstances, such as chip or board testing, the selection may be forced by configuration. Automatic operation selects a reference source based on its pre-defined priority and its current availability. A table is maintained which lists all reference sources in the order of priority. This is initially downloaded into the ACS8510 via the microprocessor interface by the Network Manager, and is subsequently modified by the results of the ongoing quality monitoring. In this way, when all the defined sources are active and valid, the source with the highest programmed priority is selected but, if this source fails, the next-highest source is selected, and so on. Restoration of repaired reference sources is handled carefully to avoid inadvertent disturbance of the output clock. The ACS8510 has two modes of operation; Revertive and Revision 1.06/October 2002 Semtech Corp. 36 Bi ts(7:3)= XXXXX Bi ts(2:0)= Pi n dependent Non-Revertive. In Revertive mode, if a revalidated (or newly validated) source has a higher priority than the reference source which is currently selected, a switch over will take place. Many applications prefer to minimise the clock switching events and choose NonRevertive mode. In Non-Revertive mode , when a re-validated (or newly validated) source has a higher priority then the selected source will be maintained. The re-validation of the reference source will be flagged in the sts_sources_valid register and, if not masked, will generate an interrupt. Selection of the re-validated source can only take place under software control the software should briefly enable Revertive mode to affect a switch-over to the higher priority source. If the selected source fails under these conditions the device will still not select the higher priority source until instructed to do so by the software, by briefly setting the Revertive mode bit. When there is a reference available with higher priority than the selected reference, there will be NO change of reference source as long as the Non-Revertive mode remains on. This is the case even if there are lower priority references available or the www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS currently selected reference fails. When the ONLY valid reference sources that are available have a lower priority than the selected reference, a failure of the selected reference will always trigger a switch-over regardless of whether Revertive or Non-Revertive mode has been chosen. Also, in a Master/Slave redundancy-protection scheme, the Slave device(s) must follow the Master device. The alignment of the Master and Slave devices is part of the protection mechanism. The availability of each source is determined by a combination of local and remote monitoring of each source. Each input reference source supplied to each ACS8510 device is monitored locally and the results are made available to other devices. Forced Control Selection A configuration register, cnfg_ref_selection, controls both the choice of automatic or forced selection and the selection itself (when forced selection is required). The forced selection of an input reference source occurs when the cnfg_ref_selection variable contains a non-zero value, the value then representing the input port required to be selected. This is not the normal mode of operation, and the cnfg_ref_selection variable is defaulted to the all-one value on reset, thereby adopting the automatic selection of the reference source. Automatic Control Selection When an automatic selection is required, the cnfg_ref_selection register must be set to all zero or all one. The configuration registers, cnfg_ref_selection_priority, held in the µP port block, consists of seven, 8 bit registers organised as one 4 bit register per input reference port. Each register holds a 4-bit value which represents the desired priority of that particular port. Unused ports should be given the value, '0000' or '1111', in the relevant register to indicate they are not to be included in the priority table. On power-up, or following a reset, the whole of the configuration file will be Revision 1.06/October 2002 Semtech Corp. 37 defaulted to the values defined by Table 4. The selection priority values are all relative to each other, with lower-valued numbers taking higher priorities. Each reference source should be given a unique number, the valid values are 1 to 15 (dec). A value of 0 disables the reference source. However if two or more inputs are given the same priority number those inputs will be selected on a first in, first out basis. If the first of two same priority number sources goes invalid the second will be switched in. If the first then becomes valid again, it becomes the second source on the first in, first out basis, and there will not be a switch. If a third source with the same priority number as the other two becomes valid, it joins the priority list on the same first in, first out basis. There is no implied priority based on the channel numbers. The input port <I_11> is for the connection of the synchronous clock of the TOUT0 output of the Master device (or the active-Slave device), to be used to align the TOUT0 output with the Master (or active-Slave) device if this device is acting in a subordinate-Slave or subordinateMaster role. Ultra Fast Switching A reference source is normally disqualified after the leaky bucket monitor thresholds have been crossed. An option for a faster disqualification has been implemented, whereby if register 48H, bit 5 (Ultra Fast Switching), is set then a loss of activity of just a few reference clock cycles will set the no activity alarm and cause a reference switch. This can be chosen to cause an interrupt to occur instead of or as well as causing the reference switch. The sts_interrupts register 05 Hex Bit 14 (main_ref_failed) of the interrupt status register is used to flag inactivity on the reference that the device is locked to much faster than the activity monitors can support. If bit 6 of the cnfg_monitors register (flag ref loss on TDO) is set, then the state of this bit is driven onto the TDO pin of the device. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS The flagging of the loss of the main reference failure on TDO is simply allowing the status of the sts_interrupt bit 14 to be reflected in the state of the TDO output pin. The pin will, therefore remain High until the interrupt is cleared. This functionality is not enabled by default so the usual JTAG functions can be used. When JTAG is normally used straight out of power-up, then this feature will have no bearing on the functionality. The TDO flagging feature will need to be disabled if JTAG is not enabled on power-up and the feature has since been enabled. When the TDO output from the ACS8510 is connected to the TDI pin of the next device in the JTAG scan chain, the implementation should be such that a logic change caused by the action of the interrupt on the TDI input should not effect the operation when JTAG is not active. External Protection Switching Fast external switching between inputs <I_3> and <I_4> can also be triggered directly from a dedicated pin (SRCSW). This mode can be activated either by holding this pin high during reset, or by writing to bit 4 of register address 48Hex. Once external protection switching is enabled, then the value of this pin directly selects either <I_3> (SRCSW high) or <I_4> (SRCSW low). If this mode is activated at reset by pulling the SRCSW pin high, then it configures the default frequency tolerance of <I_3> and <I_4> to +/- 80 ppm (register address 41Hex and 42Hex). Any of these registers can be subsequently set by external software if required. When external protection switching is enabled, the device will operate as a simple switch. All clock monitoring is disabled and the DPLL will simply be forced to try to lock on to the indicated reference source. Clock Quality Monitoring Clock quality is monitored and used to modify the priority tables of the local and remote ACS8510 devices. The following parameters are monitored: 1. Activity (toggling) 2. Frequency (This monitoring is only performed when there is no irregular operation of the clock or loss of clock condition) In addition, input ports <I_1> and <I_2> carry AMI-encoded composite clocks which are Figure 9. Inactivity and Irregularity Monitoring inactivities/irregularities reference source bucket_size leaky bucket response upper_threshold lower_threshold programmable fall slopes (all programmable) alarm Revision 1.06/October 2002 Semtech Corp. 38 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS monitored by the AMI-decoder blocks. Loss of signal is declared by the decoders when either the signal amplitude falls below +0.3 V or there is no activity for 1 ms. Any reference source which suffers a loss-ofsignal, loss-of-activity, loss-of-regularity or clockout-of-band condition will be declared as unavailable. Clock quality monitoring is a continuous process which is used to identify clock problems. There is a difference in dynamics between the selected clock and the other reference clocks. Anomalies occurring on non-selected reference sources affect only that source's suitability for selection, whereas anomalies occurring on the selected clock could have a detrimental impact on the accuracy of the output clock. Anomalies, whether affecting signal purity or signal frequency, could induce jitter or frequency offsets in the output clock, leading to anomalous behaviour. Anomalies on the selected clock, therefore, have to be detected as they occur and the phase locked loop must be temporarily isolated until the clock is once again pure. The clock monitoring process cannot be used for this because the high degree of accuracy required dictates that the process be slow. To achieve the immediacy required by the phase locked loop requires an alternative mechanism. The phase locked loop itself contains appropriate circuitry, based around the phase detector, and isolates itself from the selected reference source as soon as a signal impurity is detected. It can likewise respond to frequency offsets outside the permitted range since these result in saturation of the phase detector. When the phase locked loop is isolated from the reference source, it is essentially operating in a Holdover state; this is preferable to feeding the loop with a standby source, either temporarily or permanently, since excessive phase excursions on the output clock are avoided. Anomalies detected by the phase detector are integrated in a leaky bucket accumulator. Leaky bucket timing The time taken to raise an inactivity alarm on a reference source that has previously been fully active (leaky bucket empty) will be: (cnfg_activ_upper_threshold N) secs 8 where N is the number of the relevent leaky bucket configuration. If an input is intermittently inactive then this time can be longer. The default setting of cnfg_activ_upper_threshold is 6, therefore the default time is 0.75 s. The time taken to cancel the activity alarm on a previously completely inactive reference source is calculated as: (cnfg_decay_rate N) 2 x ((cnfg_bucket_size N) - (cnfg_activ_lower_thrshold N)) secs 8 where N is the number of the relevent leaky bucket configuration in each case. The default setting are shown in the following: 1 2 x (8-4) = 1.0 s 8 Revision 1.06/October 2002 Semtech Corp. 39 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Occasional anomalies do not cause the accumulator to cross the alarm setting threshold, so the selected reference source is retained. Persistent anomalies cause the alarm setting threshold to be crossed and result in the selected reference source being rejected. Activity Monitoring The ACS8510 has a combined inactivity and irregularity monitor. The ACS8510 uses a leaky bucket accumulator, which is a digital circuit which mimics the operation of an analog integrator, in which input pulses increase the output amplitude but die away over time. Such integrators are used when alarms have to be triggered either by fairly regular defect events, which occur sufficiently close together, or by defect events which occur in bursts. Events which are sufficiently spread out should not trigger the alarm. By adjusting the alarm setting threshold, the point at which the alarm is triggered can be controlled. The point at which the alarm is cleared depends upon the decay rate and the alarm clearing threshold. On the alarm setting side, if several events occur close together, each event adds to the amplitude and the alarm will be triggered quickly; if events occur a little more spread out, but still sufficiently close together to overcome the decay, the alarm will be triggered eventually. If events occur at a rate which is not sufficient to overcome the decay, the alarm will not be triggered. On the alarm clearing side, if no defect events occur for a sufficient time, the amplitude will decay gradually and the alarm will be cleared when the amplitude falls below the alarm clearing threshold. The ability to decay the amplitude over time allows the importance of defect events to be reduced as time passes by. This means that, in the case of isolated events, the alarm will not be set, whereas, once the alarm becomes set, it will be held on until normal operation has persisted for a suitable time (but if the operation is still erratic, the alarm will remain set). See Figure 9. Revision 1.06/October 2002 Semtech Corp. 40 The leaky bucket accumulators are programmable for size, alarm set & reset thresholds and decay rate. Each source is monitored over a 128 ms period. If, within a 128 ms period, an irregularity occurs that is not deemed to be due to allowable jitter/wander, then the accumulator is incremented. The accumulator will continue to increment up to the point that it reaches the programmed bucket size. The fill rate of the leaky bucket is, therefore, 8 units/second. The leak rate of the leaky bucket is programmable to be in multiples of the fill rate (x1, x0.5, x0.25 and x0.125) to give a programmable leak rate from 8 units/sec down to 1 unit/sec. A conflict between trying to leak at the same time as a fill is avoided by preventing a leak when a fill event occurs. Disqualification of a non-selected reference source is based on inactivity, or on an out of band result from the frequency monitors. The currently selected reference source can be disqualified for phase, frequency, inactivity or if the source is outside the DPLL lock range. If the currently selected reference source is disqualified, the next highest priority, active reference source is selected. Frequency Monitoring The ACS8510 performs frequency monitoring to identify reference sources which have drifted outside the acceptable frequency range of +/- 16.6 ppm (measured with respect to the output clock). The sts_reference_sources outof-band alarm for a particular reference source is raised when the reference source is outside the acceptable frequency range. The ACS8510 DPLL has a programmable frequency limit of +/- 80 ppm. If the range is programmed to be > 16.6 ppm, the frequency monitors should be disabled so the input reference source is not automatically rejected as out of frequency range. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Modes of Operation Locked mode The ACS8510 has three primary modes of operation (Free-run, Locked and Holdover) supported by three secondary, temporary modes (Pre-Locked, Lost_Phase and PreLocked2). These are shown in the State Transition Diagram, Figure 11. The Locked mode is used when an input reference source has been selected and the PLL has had time to lock. When the Locked mode is achieved, the output signal is in phase and locked to the selected input reference source. The selected input reference source is determined by the priority table. When the ACS8510 is in Locked mode, the output frequency and phase follows that of the selected input reference source. Variations of the external crystal frequency have a minimal effect on the output frequency. Only the minimum to maximum frequency range is affected. Note that the term, 'in phase', is not applied in the conventional sense when the ACS8510 is used as a frequency translator (e.g., when the input frequency is 2.048 MHz and the output frequency is 19.44 MHz) as the input and output cycles will be constantly moving past each other; however, this variation will itself be cyclical over time unless the input and output are not locked. The ACS8510 can operate in Forced or Automatic control. On reset, the ACS8510 reverts to Automatic Control, where transitions between states are controlled completely automatically. Forced Control can be invoked by configuration, allowing transitions to be performed under external control. This is not the normal mode of operation, but is provided for special occasions such as testing, or where a high degree of hands-on control is required. Free-run mode The Free-run mode is typically used following a power-on-reset or a device reset before network synchronization has been achieved. In the Free-run mode, the timing and synchronization signals generated from the ACS8510 are based on the Master clock frequency provided from the external oscillator and are not synchronized to an input reference source. The frequency of the output clock is a fixed multiple of the frequency of the external oscillator, and the accuracy of the output clock is equal to the accuracy of the Master clock. The transition from Free-run to Pre-locked occurs when the ACS8510 selects a reference source. Pre-Locked mode The ACS8510 will enter the Locked state in a maximum of 100 seconds, as defined by GR1244-CORE specification, if the selected reference source is of good quality. If the device cannot achieve lock within 100 seconds, it reverts to Free-run mode and another reference source is selected. Revision 1.06/October 2002 Semtech Corp. 41 Lost_Phase mode Lost-phase mode is entered when the current phase error, as measured within the DPLL, is larger than a preset limit (see register 04, bits 5:3), as a result of a frequency or phase transient on the selected reference source. This mode is similar in behavior to the Pre-locked or Pre-locked(2) modes, although in this mode the DPLL is attempting to regain lock to the same reference rather than attempt lock to a new reference. If the DPLL cannot regain lock within 100 s, the source is disqualified, and one of the following transitions takes place: 1. Go to Pre-Locked(2); - If a known-good standby source is available. 2. Go to Holdover; - If no standby sources are available. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Holdover mode The Holdover mode is used when the ACS8510 has been in Locked mode for long enough to acquire stable frequency data, but the final selected reference source has become unavailable and a replacement has not yet been qualified for selection. In Holdover mode, the ACS8510 provides the timing and synchronisation signals to maintain the Network Element (NE), but they are not phase locked to any input reference source. The timing is based on a stored value of the frequency ratio obtained during the last Locked mode period. To allow for further development of the way the internal algorithm operates, and to allow for customised switching behaviour, the switch to and from Holdover state may be controlled by external software. The device must be set in either manual mode or automatic mode: 1. Register cnfg_mode bit holdover offset en set high (manual mode). The Holdover frequency is determined by the value in register cnfg_holdover_offset. This is a 19 bit signed number, with a LSB resolution of 0.0003 ppm, which gives an adjustment range of ± 80 ppm. This value can be derived from a reading of the register sts_curr_inc_offset (addr 0D, 0C and 07) which gives, in the same format, an indication of the current output frequency deviation, which would be read when the device is locked. If required, this value could be read by an external microcontroller and averaged over the time required. The averaged value could then be fed to the cnfg_holdover_offset register ready for setting of the averaged frequency value when the device enters Holdover mode. The sts_curr_inc_offset value is internally derived from the Digital Phase Locked Loop (DPLL) integral path value, which already represents a well averaged measure of the current frequency, depending on the loop bandwidth selected. 2. Register cnfg_mode bit holdover offset en set low (automatic mode). In automatic control, the device can be run in one of two ways: 2.1 Register cnfg_holdover_offset register 40 bit 7 auto holdover averaging is set high. The value is averaged Revision 1.06/October 2002 Semtech Corp. 42 internally over 32 samples at 32 seconds apart, giving the average frequency over approximatley the last 20 minutes. The proportional DPLL path is ignored so that recent signal disturbances do not affect the Holdover frequency value. If the device has been previously correctly locked, missing pulses in the input clock stream fed to the SETS IC are ignored, hence also avoiding any frequency disturbances to the output frequency value when an input clock source fails. 2.2 Register cnfg_holdover_offset register 40 bit 7 auto holdover averaging is set low. This simply freezes the DPLL at the current frequency (as reported by the sts_curr_inc_offset register). The proportional DPLL path is ignored so that recent signal disturbances do not affect the Holdover frequency value. Automatic control with internal averaging (option 2.1) is the default condition. If the TCXO frequency is varying due to temperature fluctuations in the room, then the instantaneous value can be different from the average value, and then it may be possible to exceed the 0.05 ppm limit (depending on how extreme the temperature flucuations are). It is advantageous to shield the TCXO to slow down frequency changes due to drift and external temperature fluctuations. The frequency accuracy of Holdover mode has to meet the ITU-T, ETSI and Telcordia performance requirements. The performance of the external oscillator clock is critical in this mode, although only the frequency stability is important - the stability of the output clock in Holdover is directly related to the stability of the external oscillator. Pre-Locked(2) mode This state is very similar to the Pre-Locked state. It is entered from the Holdover state when a reference source has been selected and applied to the phase locked loop. It is also entered if the device is operating in Revertive mode and a higher-priority reference source is restored. Upon applying a reference source to the phase locked loop, the ACS8510 will enter the Locked state in a maximum of 100 seconds, as defined www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS by GR-1244-CORE specification, if the selected reference source is of good quality. If the device cannot achieve lock within 100 seconds, it reverts to Holdover mode and another reference source is selected. Protection Facility The ACS8510 supports redundancy protection. The primary functions of this include: - Alignment of the priority tables of both Master and Slave ACS8510 devices so as to align the selection of reference sources of both Master and Slave ACS8510 devices. - Alignment of the phases of the 8 kHz and 2 kHz clocks in both Master and Slave ACS8510 devices to within one cycle of the 77.76 MHz internal clock. When two ACS8510 devices are to be used in a redundancy-protection scheme within an NE, one will be designated as the Master and the other as the Slave. It is expected that an NE will use the T OUT0 output for its internal operations because the TOUT4 output is intended to feed an SSU/BITS system. An SSU/BITS will not be bothered by phase differences between signals arriving from different sources because it typically incorporates line build-out functions to absorb phase differences on reference inputs. This means that the phasing of the composite clocks between two ACS8510 devices do not have to be mutually-aligned. The same is not true, however, of the TOUT0 output signals (T01 - T07, Frame clock and Multi-Frame clock). It is usually important to align the phases of all equivalent TOUT0 signals generated by different sources so that switch-over from one device to another does not affect the internal operations of the NE. Both ACS8510 devices will produce the same signals, which will be routed around the NE to the various consumers (clock sinks). With the possible exception of a Revision 1.06/October 2002 Semtech Corp. 43 through-timing mode, the signals from the Master device will be used by all consumers, unless the Master device fails, when each consumer will switch over to the signals generated by the Slave device. Switchover to a new TOUT0 clock should be as hitless as possible. This requires the signals of both ACS8510 devices to be phase aligned at each consumer. Phase alignment requires frequency alignment. To ensure that both devices can generate output clocks locked to the same source, both devices are supplied with the same reference sources on the same input ports and will have identical priority tables. Failures of selected reference sources will result in both ACS8510 devices making the same updates to their priority tables as availability information will be updated in both devices. Although, in principle, the priority tables will be the same if the same reference sources are used on the same input port on each device, in practice, this is only true if the reference sources actually arrive at each device - failures of a source seen only by one device and not by the other, such as could be caused, for example, by a backplane connector failure, would result in the priority tables becoming misaligned. It is thus necessary to force the priority tables to be aligned under normal operating conditions so that the devices can make the same decisions - this can be achieved by loading the availability seen by one device (via the sts_reference_sources register) into the cnfg_sts_remote_sources_valid register of the other device. Another factor which could affect hit-less switching is the frequency of the local oscillator clock used by each ACS8510 device: these clocks are not mutually aligned and, whilst this has no impact on the frequency of the output clocks during locked mode, it could cause the output frequencies to diverge during Holdover mode if no action were taken to avoid it. In order to maintain alignment of the output frequencies of each ACS8510 device even www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS during Holdover, the Master device's 6.48 MHz output is fed into the Slave device on its <I_11> pin, whilst the Multi-Frame Sync (2 kHz) output is fed to the Sync2k input of the Slave. In this way, the Slave locks to the master's output and remains locked whilst the Master moves between operating states. Only when the Master fails does the Slave use its own reference inputs - should the Master have been in the Holdover state, the Slave device will see the same lack of reference sources and also enter the Holdover state. This scheme also provides a convenient way to phase-align all TOUT0 output clocks in Master and Slave devices, and also to detect the failure of the Master device. If a Master device fails, the Slave has to take over responsibility for the generation of the output clocks, including the 8 kHz and 2 kHz Frame and Multi-Frame clocks. The Slave device is also given responsibility for building the priority table and performing the reference switching operations. The Slave device, therefore, adopts a more active role when the Master has failed. The cnfg_mode register 34 (Hex) Bit 1 contains the Master/Slave control bit to determine the designation of the device. To restore redundancy protection, the Master has to be repaired and replaced. When this occurs, the new Master cannot immediately adopt its normal role because it must not cause phase hits on the output clocks. It has, therefore, to adopt a subordinate role to the active Slave device, at least until such time as it has acquired alignment to the 8 kHz and 2 kHz frame and Multi-Frame clocks and the priority table of the Slave device; then, when a switch-back (restoration) is ordered, the Master can take over responsibility. These activities, in Master or Slave operation, are summarized in Table 12 and described in detail in Application Note AN-SETS-2. Revision 1.06/October 2002 Semtech Corp. 44 Alignment of Priority Tables in Master and Slave ACS8510 Correct protection will only be achieved by connecting individual reference sources to the same input ports on each device and priority tables in each device must be aligned to each other. The Master device must take account of the availability of each reference source seen by another device and a Slave device must adopt the same order of priority as the Master device (except that the Slave's highest-priority input is <I_11>). Both devices monitor the reference sources and decide the availability of each source; if the failure of a reference source is seen by both devices, they will both update their priority tables - however, if the reference source failure is only seen by one device and not by both, the priority tables could get out of step: this could be catastrophic if it resulted in two devices choosing different reference sources since any slight differences in frequency variation over time (e.g. wander) would mis-align the phase of the 8 kHz Frame and 2 kHz MultiFrame clocks produced by the individual devices, resulting in phase hits on switch-over. It is therefore important that the same priority table be built by each device, using the reference source availability seen by each device. The monitoring of the reference sources performed by a Master ACS8510 results in a list of available sources being placed in a sts_valid_sources register. This information is used within the device as one of the masks used to build the device's priority table. The information is passed to the Slave device and used to configure the cnfg_sts_remote_ sources_valid register so that it can use it as a mask in building its own priority tables. The information is passed between devices using the microprocessor port. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Alignment of the Selection of Reference Sources for T OUT4 Generation in the Master and Slave ACS8510 As stated previously, there is no need to align the phases of the TOUT4 outputs in Master and Slave devices. There is a need, however, to ensure that all devices select the same reference source. But, since there is no Holdover mode required for the generation of the TOUT4 clock, and every reference source is continuously monitored within each device, it is permissible to rely on external intelligence to command a switch-over to an alternative source should the selected one fail. The time delay involved in detecting the failure, indicating it to the outside and selecting a new source, will result only in the SSU/BITS entering its Holdover mode for a short time. Alignment of the Phases of the 8kHz and 2kHz Clocks in both Master and Slave ACS8510 In addition to aligning the edges of the TOUT0 outputs of Master and Slave devices, it is necessary to align the edges of the Frame and Multi-Frame clocks. If this is not performed, frame alignment may be lost in distant equipment on switch-over to an alternative device, resulting in anomalous network operation of a very serious nature. In accordance with the alignment mechanism used with the main TOUT0 clock (described in the opening paragraphs of this section), whereby the 6.48 MHz output of the Master device is supplied to the Slave device, the alignment of both the 8 kHz and 2 kHz clocks is accomplished (they are already synchronous to the TOUT0 clocks) by feeding the 2 kHz clock of the Master device into the Slave device. The Multi-Frame Sync clock output of the Slave device is also fed to the Sync2K input of the Master device. Alignment of the Multi-Frame Revision 1.06/October 2002 Semtech Corp. 45 Sync input occurs only when cnfg_mode register, bit 3, address 34Hex External 2 kHz Sync Enable is set to 1. JTAG The JTAG connections on the ACS8510 allow a full boundary scan to be made. The JTAG implementation is fully compliant to IEEE 1149.1, with the following minor exceptions, and the user should refer to the standard for further information. 1. The output boundary scan cells do not capture data from the core, and so do not support EXTEST. However this does not affect board testing. 2. In common with some other manufacturers, pin TRST is internally pulled low to disable JTAG by default. The standard is to pull high. The polarity of TRST is as the standard: TRST high to enable JTAG boundary scan mode, TRST low for normal operation. 3. The device does not support the optional tri-state capability (HIGHZ). This will be supported on the next revision of the device. The JTAG timing diagram is shown in Figure 17. PORB The Power On Reset (PORB) pin resets the device if forced Low for a power on reset to be initiated. The reset is asynchronous, the minimum Low pulse width is 5 ns. Reset is needed to initialize all of the register values to their defaults. Asserting Reset is required at power on, and may be re-asserted at any time to restore defaults. This is implemented most simplistically by an external capacitor to GND along with the internal pull-up resistor. The ACS8510 is held in a reset state for 250 ms after the PORB pin has been pulled High. In normal operation PORB should be held High. www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 10. Master-Slave Schematic TCXO V DD MASTER 6.48 MHz MSTSLVB T 01 SEC1 I_1 T 02 SEC2 I_2 T 03 SEC3 I_3 . . . T 04 . . . I_11 . . . I_14 T 07 . . . T 011 SEC14 MFr S ync SYNC2K 6.48 MHz TCXO SLAVE GND MSTSLVB T 01 SEC1 I_1 T 02 SEC2 I_2 T 03 SEC3 I_3 . . . T 04 . . . I_11 T 07 . . . T 011 SEC13 . . . I_14 MFr S ync SYNC2K SYNC2K_EN=1 34Bit3 Table 13. Master-Slave Relationship R e f _ so u r ce s t o M ast e r A C S 8510 R e f _ so u r ce s t o S l av e A C S 8510 M ast e r A C S 8510 s t at u s S l av e A C S 8510 s t at u s M ast e r A C S 8510 S l av e A C S 8510 ou t p u t C om m en t s A ll good A ll good Good Good Locked (ref_x) Locked to master N ote 1 Some failed Some oth ers failed Good Good Locked (ref_y) Locked to master N ote 1 Good Good Good Failed Locked (ref_x) Dead Good Good Failed Good Dead Locked (ref_x) Good Good Failed Failed Dead Dead Failed Failed Failed Good Hold over Locked to master Failed Failed Good Failed Hold over Dead Failed Failed Failed Good Dead Hold over Failed Failed Failed Failed Dead Dead N ote 2 N ote 3 Notes to Table 13 Note 1: Both ACS8510 must build a common priority table so that the Slave ACS8510 can select the same input reference source as the Master ACS8510 if the Master fails (when the Master is OK, the Slave locks to the Master's output). Note 2: Slave ACS8510 uses common priority table, built before Master ACS8510 failed - priority table can be modified as status of the input reference sources changes Note 3: Slave ACS8510 outputs must remain in phase with those of Master ACS8510 Revision 1.06/October 2002 Semtech Corp. 46 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 11. Automatic Mode Control State Diagram (1)Reset free-run select ref (state 001) (2) all refs evaluated & at least one ref valid (3) no valid standby ref & (main ref invalid or out of lock >100s) Reference sources are flagged as ’valid’ when active, ’in-band’ and have no phase alarm set. (4) valid standby ref & [ main ref invalid or (higher-priority ref valid & in revertive mode) or out of lock >100s] pre-locked w ait for up to 100s (state 110) (5) selected ref phase locked All sources are continuously checked for activity and frequency. Only the main source is checked for phase. A phase lock alarm is only raised on a reference when that reference has lost phase whilst being used as the main reference. The micro-processor can reset the phase lock alarm. A source is considered to have phase locked when it has been continuously in phase lock for between 1 and 2 seconds locked keep ref (state 100) (10) selected source phase locked (9) valid standby ref & [ main ref invalid or (higher-priority ref valid & in revertive mode) ] pre-locked2 w ait for up to 100s (state 101) (12) valid standby ref & (main ref invalid or out of lock >100s) (15) valid standby ref & [ main ref invalid or (higher-priority ref valid & in revertive mode) or out of lock >100s] Revision 1.06/October 2002 Semtech Corp. (8) phase regained within 100s (6) no valid standby ref & main ref invalid (7) phase lost on main ref Lost phase w ait for up to 100s (state 111) (11) no valid standby ref & (main ref invalid or out of lock >100s) holdover select ref (state 010) (13) no valid standby ref & (main ref invalid or out of lock >100s) (14) all refs evaluated & at least one ref valid 47 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Electrical Specification Important Note: The Absolute Maximum Ratings are stress ratings only, and functional operation of the device at conditions other than those indicated in the Operating Conditions sections of this specification are not implied. Exposure to the absolute maximum ratings for an extended period may reduce the reliability or useful lifetime of the product. Table 14. Absolute Maximum Ratings PA RA MET ER SYM B OL MIN MA X U N IT S Sup p ly Voltage VDD, VD+, V A1+,V A2+ VDD -0.5 3.6 V Inp ut Voltage (non-sup p ly p ins) V in - 5.5 V Outp ut Voltage (non-sup p ly p ins) Vout - 5.5 V TA -40 +85 °C Tstor -50 +150 °C A mb ient Op erating Temp erature Range Storage Temp erature Table 15. Operating Conditions PA RA MET ER SYM B OL MIN T YP MA X U N IT S Pow er Sup p ly (d c voltage) V DD, V D+,VA 1+, VA 2+, VA MI+, V DD_DIFF V DD 3.0 3.3 3.6 V Pow er Sup p ly (d c voltage) V DD5 V DD5 3.0 3.3/5.0 5.5 V A mb ient temp erature Range TA -40 - +85 °C Sup p ly current IDD - 110 200 mA Total p ow er d issip ation PTOT - 360 720 mW (Typ ical - one 19 MHz outp ut) Table 16. DC Characteristics: TTL Input Port Across all operating conditions, unless otherwise stated PA R A M E T E R SYM B OL MIN T YP MA X U N IT S V in High V ih 2.0 - - V V in Low V il - - 0.8 V Inp ut current Ii n - - 10 µA Revision 1.06/October 2002 Semtech Corp. 48 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 17. DC Characteristics: TTL Input Port with Internal Pull-up Across all operating conditions, unless otherwise stated PA R A M E T E R SYM B OL MIN T YP MA X U N IT S V in High V ih 2.0 - - V V in Low V il - - 0.8 V Pull-up resistor PU 30 - 80 kW Inp ut current Ii n - - 120 µA Table 18. DC Characteristics: TTL Input Port with Internal Pull-down Across all operating conditions, unless otherwise stated PA R A M E T E R SYM B OL MIN T YP MA X U N IT S V in High V ih 2.0 - - V V in Low V il - - 0.8 V Pull-d ow n resistor PD 30 - 80 kW Inp ut current Ii n - - 120 µA Table 19. DC Characteristics: TTL Output Port Across all operating conditions, unless otherwise stated PA R A M E T E R SYM B OL MIN T YP MA X U N IT S Vout Low Iol = 4mA Vol 0 - 0.4 V Vout High Ioh = 4mA Voh 2.4 - Drive current ID - - Revision 1.06/October 2002 Semtech Corp. 49 V 4 mA www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 20. DC Characteristics: PECL Input/Output Port Across all operating conditions, unless otherwise stated PA R A M E T E R SYM B OL MIN T YP MA X U N IT S V ILPECL V DD-2.5 - V DD-0.5 V Differential inp uts (N ote 1) V IHPECL V DD-2.4 - V DD-0.4 V Inp ut Differential voltage V IDPECL 0.1 - 1.4 V V ILPECL_S V DD-2.4 - V DD-1.5 V V IHPECL_S V DD-1.3 - V DD-0.5 V IIHPECL -10 - +10 µA IILPECL -10 - +10 µA V OLPECL V DD-2.10 - V DD-1.62 V V OHPECL V DD-1.25 - V DD-0.88 V V ODPECL 580 - 900 mV PECL Inp ut Low voltage Differential inp uts (N ote 1) PECL Inp ut High voltage PECL Inp ut Low voltage Single end ed inp ut (N ote 2) PECL Inp ut High voltage Single end ed inp ut (N ote 2) Inp ut High current Inp ut d ifferential voltage V ID = 1.4v Inp ut Low current Inp ut d ifferential voltage V ID = 1.4v PECL Outp ut Low voltage (N ote 3) PECL Outp ut High voltage (N ote 3) PECL Outp ut Differential voltage (N ote 1) Notes to Table 20 Unused differential input ports should be left floating and set in LVDS mode, or the positive and negative inputs tied to VDD and GND respectively. Note 1. Assuming a differential input voltage of at least 100 mV. Note 2. Unused differential input terminated to VDD-1.4 V. Note 3. With 50 W load on each pin to VDD-2 V. i.e. 82 W to GND and 130 W to VDD. Revision 1.06/October 2002 Semtech Corp. 50 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 12. Recommended Line Termination for PECL Input/Output Ports V DD 8kHz, 1.544/2.048, 6.48, 19.44, 38.88, 51.84, 77.76 or 155.52 MHz ZO=50Ω V DD 130R ZO=50Ω I5POS ZO=50Ω 130R 82R 130R T06POS ZO=50Ω I5NEG 130R 82R T06NEG 82R 82R GND GND V DD 8kHz, 1.544/2.048, 6.48, 19.44, 38.88, 51.84, 77.76 or 155.52 MHz ZO=50Ω V DD 130R ZO=50Ω 130R 82R 130R T07POS I6POS ZO=50Ω 19.44, 38.88, 155.52, 311.04 MHz & DIG1 ZO=50Ω 130R 82R 19.44, 51.84, 77.76, 155.52 MHz T07NEG I6NEG 82R 82R GND GND VDD = +3.3 V Revision 1.06/October 2002 Semtech Corp. 51 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 21. DC Characteristics: LVDS Input/Output Port Across all operating conditions, unless otherwise stated PA R A M E T E R SYM B OL MIN T YP MA X U N IT S V VRLVDS 0 - 2.40 V VDITH -100 - +100 mV VIDLVDS 0.1 - 1.4 V R T E RM 95 100 105 W V OHLVDS - - 1.585 V V OLLVDS 0.885 - - V V ODLVDS 250 - 450 mV V DOSLVDS - - 25 mV V OSLVDS 1.125 - 1.275 V LV DS Inp ut voltage range Differential inp ut voltage = 100 mV LV DS Differential inp ut th resh old LV DS Inp ut Differential voltage LV DS Inp ut termination resistance Must b e p laced externally across th e LV DS+/- inp ut p ins of A CS8510. Resistor sh ould b e 100W w ith 5% tolerance LV DS Outp ut h igh voltage (N ote 1) LV DS Outp ut low voltage (N ote 1) LV DS Differential outp ut voltage (N ote 1) LV DS Ch ange in magnitud e of d ifferential outp ut voltage for comp limentary states (N ote 1) LV DS outp ut offset voltage Temp erature = 25°C (N ote 1) Note to Table 21 Note 1. With 100 W load between the differential outputs. Revision 1.06/October 2002 Semtech Corp. 52 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 13. Recommended Line Termination for LVDS Input/Output Ports 8kHz, 1.544/2.048, 6.48, 19.44, 38.88, 51.84, 77.76 or 155.52 MHz 8kHz, 1.544/2.048, 6.48, 19.44, 38.88, 51.84, 77.76 or 155.52 MHz ZO=50Ω ZO=50Ω I5POS ZO=50Ω T06POS 100R ZO=50Ω I5NEG T06NEG I6POS T07POS ZO=50Ω ZO=50Ω 100R 19.44, 38.88, 155.52, 311.04 MHz & DIG1 ZO=50Ω 100R Revision 1.06/October 2002 Semtech Corp. ZO=50Ω 100R 19.44, 51.84, 77.76, 155.52 MHz T07NEG I6NEG 53 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS DC Characteristics: AMI Input/Output Port Across all operating conditions, unless otherwise stated The Alternate Mark Inversion (AMI) signal is DC balanced and consists of positive and negative pulses with a peak to peak voltage of 2.0 +/- 0.2 V. The electrical specifications are taken from option a) of Table 2/G.703 - Digital 64 kbit/s centralized clock interface, from ITU G.703. Table 22. DC Characteristics: AMI Input/Output Port PA R A M E T E R SYM B OL MIN T YP MA X U N IT S Inp ut Pulse w id th t PW 1.56 7.8 14.04 us Inp ut Pulse rise/fall time tR/F - - 5 us A MI Inp ut voltage h igh V IH A M I 2.5 - VDD + 0.3 V A MI Inp ut voltage mid d le V V IM A M I 1.5 1.65 1.8 V A MI Inp ut voltage low V V IL A M I 0 - 1.4 V A MI Outp ut current d rive IAMIOUT - - 20 mA VOH AMI V DD - 0.16 - - V Outp ut current = 20mA VOLAMI - - 0.16 V N ominal test load imp ed ence RTEST - 110 - W "Mark" amp litud e after transformer V MA R K 0.9 1.0 1.1 V "Sp ace" amp litud e after transformer V SPACE -0.1 0 0.1 V A MI Outp ut h igh voltage Outp ut current = 20mA A MI Outp ut low voltage The electrical characteristics of 64 kbits/s interface are as follows; Nominal bit rate: 64 kbit/s. The tolerance is determined by the network clock stability. There should be a symmetrical pair carrying the composite timing signal (64 kHz and 8 kHz). The use of transformers is recommended. Over-voltage protection requirement; refer to Recommendation K.41. Code conversion rules; The data signals are coded in AMI code with 100% duty cycle. The composite clock timing signals convey the 64 kHz bit-timing information using AMI coding with a 50% to 70% duty ratio and the 8 kHz octet phase information by introducing violations in the code rule. The structure of the signals and voltage levels are shown in Figures 14 and 15. Revision 1.06/October 2002 Semtech Corp. 54 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 14. Signal Structure of 64 kHz/8kHz Central Clock Interface after suitable input/output transformer (also see Figure 6/G.703) 15.6us 7.8us +1.0VIH 1V 2Vp-p 0VIM 1V -1.0VIL Figure 15. AMI Input and Output Signal Levels 15.6us Signal structure of 64 kHz/ 8 kHz central clock interface after suitable transformer. 7.8us +VDD 15.6us 7.8us +1.0VIH 0V I_1 1V 2Vp-p TO8POS C1 0VIM C2 15.6us -1.0VIL 1V I_2 TO8NEG 7.8us +VDD C1 0V Revision 1.06/October 2002 Semtech Corp. 55 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 16. Recommended Line Termination for AMI Output/Output Ports AMI input signal Turns ratio 1:1 <I_1> C1 C2 AMI input signal <I_2> AMI output signal to external devices TO8POS TO8NEG R load C3 GND C1 Notes The AMI inputs <I_1> and <I_2> should be connected to the external AMI clock source by 470 nF coupling capacitor C1. The AMI differential output TO8POS/TO8NEG should be coupled to a line transformer with a turns ration of 3:1. Components C2 = 470 pF and C3 = 2 nF. If a transformer with a turns ratio of 1:1 is used, a 3:1 ratio potential divider Rload must be used to achieve the required 1 V pp voltage level for the positive and negative pulses. Revision 1.06/October 2002 Semtech Corp. 56 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 23. DC Characteristics: Output Jitter Generation (Test Definition G.813) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m e asu r e m e n t o n A C S 8510 R ev 2 G.813 for 155.52 MHz op tion 1 500 Hz to 1.3 MHz UIpp = 0.5 0.058 (N ote 2) G.813 for 155.52 MHz op tion 1 65 kHz to 1.3 MHz UIpp = 0.1 0.048 (N ote 3) 0.048 (N ote 2) 0.053 (N ote 4) 0.053 (N ote 5) 0.058 (N ote 6) 0.053 (N ote 7) G.813 for 155.52 MHz op tion 2 12 kHz to 1.3 MHz UIpp = 0.1 0.053 (N ote 2) 0.058 (N ote 3) 0.057 (N ote 8) 0.055 (N ote 9) 0.057 (N ote 10) 0.057 (N ote 11) 0.057 (N ote 12) 0.053 (N ote 13) G.813 & G.812 for 2.048 MHz op tion 1 UIpp = 0.05 20 Hz to 100 kHz 0.046 (N ote 14) Table 24. DC Characteristics: Output Jitter Generation (Test Definition G.812) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m e asu r e m e n t o n A C S 8510 R ev 2 G.812 for 1.544 MHz 10 Hz to 40 kHz UIpp = 0.05 0.036 (N ote 14) G.812 for 155.52 MHz electrical 500 Hz to 1.3 MHz UIpp = 0.5 0.058 (N ote 15) G.812 for 2.048 MHz electrical 65 kHz to 1.3 MHz U Ip p = 0.075 0.048 (N ote 15) Revision 1.06/October 2002 Semtech Corp. 57 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 25. DC Characteristics: Output Jitter Generation (Test Definition ETS-300-462-3) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m e asu r e m e n t o n A C S 8510 R ev 2 ETS-300-462-3 for 2.048 MHz SEC 20 Hz to 100 kHz UIpp = 0.5 0.046 ( N ote 14) ETS-300-462-3 for 2.048 MHz SEC ( Filter sp ec 49 Hz to 100 kHz) 20 Hz to 100 kHz UIpp = 0.2 0.046 ( N ote 14) ETS-300-462-3 for 2.048 MHz SSU 20 Hz to 100 kHz UIpp = 0.05 0.046 ( N ote 14) ETS-300-462-3 for 155.52 MHz 500 Hz to 1.3 MHz UIpp = 0.5 0.058 ( N ote 15) ETS-300-462-3 for 155.52 MHz 65 kHz to 1.3 MHz UIpp = 0.1 0.048 ( N ote 15) Table 26. DC Characteristics: Output Jitter Generation (Test Definition GR-253-CORE) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m e asu r e m e n t o n A C S 8510 R ev 2 GR-253-CORE net i/f, 51.84 MHz 100 Hz to 400 kHz UIpp = 1.5 0.022 (N ote 15) GR-253-CORE net i/f, 51.84 MHz (Filter sp ec 20 kHz to 400 kHz) 18 kHz to 400 kHz UIpp = 0.15 0.019 (N ote 15) GR-253-CORE net i/f, 155.52 MHz 500 Hz to 1.3 MHz UIpp = 1.5 0.058 (N ote 15) GR-253-CORE net i/f, 155.52 MHz 65 kHz to 1.3 MHz UIpp = 0.15 0.048 (N ote 15) GR-253-CORE cat II elect i/f, 155.52 MHz UIpp = 0.1 0.057 (N ote 15) 12 kHz to 400 kHz UIrms = 0.01 0.006 (N ote 15) GR-253-CORE cat II elect i/f, 51.84 MHz 12 kHz to 1.3 MHz UIpp = 0.1 0.017 (N ote 15) UIrms = 0.01 0.003 (N ote 15) GR-253-CORE DS1 i/f, 1.544 MHz UIpp = 0.1 0.036 (N ote 14) 10 Hz to 40 kHz UIrms = 0.01 0.0055 (N ote 14) Revision 1.06/October 2002 Semtech Corp. 58 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 27. DC Characteristics: Output Jitter Generation (Test Definition AT&T 62411) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m e asu r e m e n t o n A C S 8510 R ev 2 AT&T 62411 for 1.544 MHz (Filter sp ec 10 Hz to 8 kHz) 10 Hz to 40 kHz UIrms = 0.02 0.0055 (N ote 14) AT&T 62411 for 1.544 MHz 10 Hz to 40 kHz UIrms = 0.025 0.0055 (N ote 14) AT&T 62411 for 1.544 MHz 10 Hz to 40 kHz UIrms = 0.025 0.0055 (N ote 14) AT&T 62411 for 1.544 MHz Broad b and UIrms = 0.05 0.0055 (N ote 14) Table 28. DC Characteristics: Output Jitter Generation (Test Definition G.742) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m easu r em en t on A C S 8510 R ev 2 G.742 for 2.048 MHz DC to 100 kHz UIpp = 0.25 0.047 (N ote 14) G.742 for 2.048 MHz (Filter sp ec 18 kHz to 100 kHz) 20 Hz to 100 kHz UIpp = 0.05 0.046 (N ote 14) G.742 for 2.048 MHz 20 Hz to 100 kHz UIpp = 0.05 0.046 (N ote 14) Table 29. DC Characteristics: Output Jitter Generation (Test Definition TR-NWT-000499) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m easu r em en t on A C S 8510 R ev 2 TR-N WT-000499 & G824 for 1.544 MHz 10 Hz to 40 kHz UIpp = 5.0 0.036 (N ote 14) TR-N WT-000499 & G824 for 1.544 MHz (Filter sp ec 8 kHz to 40 kHz) 10 Hz to 40 kHz UIpp = 0.1 0.036 (N ote 14) Revision 1.06/October 2002 Semtech Corp. 59 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 30. DC Characteristics: Output Jitter Generation (Test Definition GR-1244-CORE) Across all operating conditions, unless otherwise stated Output jitter generation measured over 60 seconds interval, UI pp max measured using Vectron 6664 12.8 MHz TCXO on ICT Flexacom + 10 MHz reference from Wavetek 905. Te s t d e f i n i t i o n F i l t e r u se d U I sp e c U I m e asu r e m e n t o n A C S 8510 R ev 2 GR-1244-CORE for 1.544 MHz >10 Hz UIpp = 0.05 0.036 (N ote 14) Notes for Tables 23 - 30 Note 1. Filter used is that defined by test definition unless otherwise stated Note 2. 5 Hz bandwidth, 19.44 MHz direct lock Note 3. 5 Hz bandwidth, 8 kHz lock Note 4. 20 Hz bandwidth, 19.44 MHz direct lock Note 5. 20 Hz bandwidth, 8 kHz lock Note 6. 10 Hz bandwidth, 19.44 MHz direct lock Note 7. 10 Hz bandwidth, 8 kHz lock Note 8. 2.5 Hz bandwidth, 19.44 MHz direct lock Note 9. 2.5 Hz bandwidth, 8 kHz lock Note 10. 1.2 Hz bandwidth, 19.44 MHz direct lock Note 11. 1.2 Hz bandwidth, 8 kHz lock Note 12. 0.6 Hz bandwidth, 19.44 MHz direct lock Note 13. 0.6 Hz bandwidth, 8 kHz lock Note 14. 5 Hz bandwidth, 8 kHz lock, 2.048 MHz input Note 15. 5 Hz bandwidth, 8 kHz lock, 19.44 MHz input Revision 1.06/October 2002 Semtech Corp. 60 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 17. JTAG Timing t CYC TCK t S UR t HT TM S TDI t D OD TDO Table 31. JTAG Timing (for use with Figure 17) PA R A M E T E R SYM B OL MIN T YP MA X U N IT S Cycle time tCYC 50 - - ns TMS/TDI to TCK rising edge t i me tSUR 3 - - ns TCK rising to TMS/TDI hold t i me tHT 23 - - ns TCK falling to TDO valid tDOD - - 5 ns Revision 1.06/October 2002 Semtech Corp. 61 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 18. Input/Output Timing 7\SLFDO ,QSXW2XWSXW 'HOD\ 7\SLFDO N+]LQSXW 2XWSXW QV 3KDVH $OLJQPHQW N+]RXWSXW N+] 0+]LQSXW N+] QV WRQV 0+]RXWSXW 7 WRQV 0XOWLSOHVKDYHWKH VDPHRIIVHW 0+]LQSXW ( WRQV 0XOWLSOHVKDYHWKH VDPHRIIVHW WRQV 0+]RXWSXW 0+] WRQV 0+] WRQV 0+] WRQV 0+] WRQV 0+] WRQV 0+]LQSXW WRQV 0+]RXWSXW 0+]LQSXW WRQV 0+]RXWSXW $GGLWLRQDOGHOD\ IRUWKLVRXWSXW 0+]LQSXW 0+] WRQV WRQV 0+]RXWSXW 0+] QV 0+] QV 0+]LQSXW WRQV 0+]RXWSXW Revision 1.06/October 2002 Semtech Corp. 62 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Microprocessor Interface Timing Motorola Mode In MOTOROLA mode, the device is configured to interface with a microprocessor using a 680x0 type bus. The following figures show the timing diagrams of write and read accesses for this mode. Figure 19. Read Access Timing in MOTOROLA Mode t pw1 CSB t su2 WRB t h2 X X t h1 t su1 A X address X t d1 AD t d3 Z t d2 RDY (DTACK) Z data t pw2 t h3 t d4 Z Z Table 32. Read Access Timing in MOTOROLA Mode (for use with Figure 19) Sy m b ol tsu1 tsu2 P ar am e t e r Setup A valid to CSBfalling edge Setup WRB valid to CSBfalling edge MIN T YP MA X 0 ns - - 0 ns - - td1 Delay CSBfalling edge to A D valid - - 177 ns td 2 Delay CSBfalling edge to DTA CKrising edge - - 13 ns td 3 Delay CSBrising edge to A D h igh -Z - - 0 ns td 4 Delay CSBrising edge to RDY h igh -Z - - 7 ns tp w 1 CSB low time 485 ns(1) - - tpw2 RDY h igh time 310 ns - 472 ns th 1 Hold A valid after CSBrising edge 0 ns - - th2 Hold WRB h igh after CSBrising edge 0 ns - - th3 Hold CSB low after RDYfalling edge 0 ns - - tp Time b etw een consecutive accesses (CSBrising edge to CSBfalling edge) 320 ns - - Note 1: Timing with RDY. If RDY not used, tpw1 becomes 178 ns. Revision 1.06/October 2002 Semtech Corp. 63 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 20. Write Access Timing in MOTOROLA Mode t pw1 CSB t su2 WRB t h2 X X t h1 t su1 A X address X t h4 t su3 AD X data t d2 RDY (DTACK) t pw2 X t h3 t d4 Z Z Table 33. Write Access Timing in MOTOROLA Mode (for use with Figure 20) Sy m b ol tsu1 P ar am e t e r Setup A valid to CSBfalling edge MIN T YP MA X 0 ns - - tsu2 Setup WRB valid to CSBfalling edge 0 ns - - tsu3 Setup A D valid b efore CSBrising edge 3 ns - - td2 Delay CSBfalling edge to RDYrising edge - - 13 ns td 4 Delay CSBrising edge to RDY h igh -Z - - 7 ns tp w 1 CSB low time 485 ns(1) - - tpw2 RDY h igh time 310 ns - 472 ns th 1 Hold A valid after CSBrising edge 3 ns - - th2 Hold WRB low after CSBrising edge 0 ns - - th3 Hold CSB low after RDYfalling edge 0 ns - - th4 Hold A D valid after CSBrising edge 4 ns tp Time b etw een consecutive accesses (CSBrising edge to CSBfalling edge) - - 320 ns Note 1: Timing with RDY. If RDY not used, tpw1 becomes 178 ns. Revision 1.06/October 2002 Semtech Corp. 64 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Intel Mode In INTEL mode, the device is configured to interface with a microprocessor using a 80x86 type bus. The following figures show the timing diagrams of write and read accesses for this mode. Figure 21. Read Access Timing in INTEL Mode CSB WRB t su2 t pw 1 t h2 RDB t su 1 t h1 A ad d ress t d1 AD Z d ata t d2 RDY t d4 Z t d3 t pw 2 t h3 t d5 Z Z Table 34. Read Access Timing in INTEL Mode (for use with Figure 21) Sy m b ol tsu1 tsu2 P ar am e t e r Setup A valid to CSBfalling edge Setup CSBfalling edge to RDBfalling edge MIN T YP MA X 0 ns - - 0 ns - - td1 Delay RDBfalling edge to A D valid - - 177 ns td 2 Delay CSBfalling edge to RDY active - - 13 ns td 3 Delay RDBfalling edge to RDYfalling edge - - 14 ns td4 Delay RDBrising edge to A D h igh -Z - - 10 ns td 5 Delay CSBrising edge to RDY h igh -Z tp w 1 RDB low time 486 ns(1) - - tpw2 RDY low time 310 ns - 472 ns th 1 Hold A valid after RDBrising edge 0 ns - - th2 Hold CSB low after RDBrising edge 0 ns - - th3 Hold RDB low after RDYrising edge 0 ns - - tp Time b etw een consecutive accesses (RDBrising edge to RDBfalling edge , or RDBrising edge to WRBfalling edge) 320 ns - - 9 ns Note 1: Timing with RDY. If RDY not used, tpw1 becomes 180 ns. Revision 1.06/October 2002 Semtech Corp. 65 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 22. Write Access Timing in INTEL Mode CSB t su2 t pw1 t h2 WRB RDB t su1 t h1 A address t su3 data AD t d2 RDY t h4 t d3 t pw2 t h3 t d5 Z Z Table 35. Write Access Timing in INTEL Mode (for use with Figure 22) S y m b ol tsu1 tsu2 P ar am e t e r Setup A valid to CSBfalling edge Setup CSBfalling edge to WRBfalling edge MIN T YP MA X 0 ns - - 0 ns - - tsu3 Setup A D valid to WRBrising edge 3 ns - - td2 Delay CSBfalling edge to RDY active - - 13 ns td 3 Delay WRBfalling edge to RDYfalling edge - - 14 ns td5 Delay CSBrising edge to RDY h igh -Z tp w 1 WRB low time 486 ns(1) - - tpw2 RDY low time 310 ns - 472 ns th 1 Hold A valid after WRBrising edge 170 ns(2) - - th2 Hold CSB low after WRBrising edge 0 ns - - th3 Hold WRB low after RDYrising edge 0 ns - - th4 Hold A D valid after WRBrising edge 4 ns tp Time b etw een consecutive accesses (WRBrising edge to WRBfalling edge , or WRBrising edge to RDBfalling edge) - - 9 ns 320 ns Note 1: Timing with RDY. If RDY not used, tpw1 becomes 180 ns. Note 2: Timing if th2 is greater than 170 ns, otherwise 5 ns after CSB rising edge. Revision 1.06/October 2002 Semtech Corp. 66 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Multiplexed Mode In MULTIPLEXED mode, the device is configured to interface with a microprocessor using a multiplexed address/ data bus. The following figures show the timing diagrams of write and read accesses for this mode. Figure 23. Read Access Timing in MULTIPLEXED Mode t t pw 3 p1 ALE t su1 t h1 CSB t su2 WRB t t pw 1 h2 RDB t X a d d re s s AD t RDY t d1 d4 X d a ta t d2 d3 t pw 2 t t h3 d5 Z Z Table 36. Read Access Timing in MULTIPLEXED Mode (for use with Figure 23) S y m b ol tsu1 P ar am e t e r Setup A D ad d ress valid to A LEfalling edge MIN T YP MA X 2 ns - - tsu2 Setup CSBfalling edge to RDBfalling edge 0 ns - - td1 Delay RDBfalling edge to A D d ata valid - - 177 ns td 2 Delay CSBfalling edge to RDY active - - 13 ns td 3 Delay RDBfalling edge to RDYfalling edge - - 15 ns td 4 Delay RDBrising edge to A D d ata h igh -Z - - 9 ns td 5 Delay CSBrising edge to RDY h igh -Z - - 10 ns tp w 1 RDB low time - - tpw2 RDY low time 310 ns - 472 ns tp w 3 A LE h i gh t i me 2 ns th 1 Hold A D ad d ress valid after A LEfalling edge 3 ns - - th2 Hold CSB low after RDBrising edge 0 ns - - th3 Hold RDB low after RDYrising edge 0 ns - - tp1 Time b etw een A LEfalling edge and RDBfalling edge 0 ns - - tp2 Time b etw een consecutive accesses ( RDBrising edge to A LErising edge) 320 ns - - 487 ns ( 1) Note 1: Timing with RDY. If RDY not used, tpw1 becomes 180 ns. Revision 1.06/October 2002 Semtech Corp. 67 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Figure 24. Write Access Timing in MULTIPLEXED Mode t t pw 3 p1 ALE t t su1 h1 CSB t t su 2 t pw 1 h2 W RB RDB t X a d d re s s AD t RDY t su3 h4 X d a ta t d2 d3 t pw 2 t h3 t d5 Z Z Table 37. Write Access Timing in MULTIPLEXED Mode (for use with Figure 24) S y m b ol tsu1 P ar am e t e r Setup A D ad d ress valid to A LEfalling edge MIN T YP MA X 2 ns - - tsu2 Setup CSBfalling edge to WRBfalling edge 0 ns - - tsu3 Setup A D d ata valid to WRBrising edge 3 ns - - td2 Delay CSBfalling edge to RDY active - - 13 ns td 3 Delay WRBfalling edge to RDYfalling edge - - 15 ns td 5 Delay CSBrising edge to RDY h igh -Z tp w 1 WRB low time 487 ns(1) - - tpw2 RDY low time 310 ns - 472 ns tp w 3 A LE h i gh t i me 2 ns - - th 1 Hold A D ad d ress valid after A LEfalling edge 3 ns - - th2 Hold CSB low after WRBrising edge 0 ns - - th3 Hold WRB low after RDYrising edge 0 ns - - th4 A D d ata h old valid after WRBrising edge 4 ns tp1 Time b etw een A LEfalling edge and WRBfalling edge 0 ns - - tp2 Time b etw een consecutive accesses (WRBrising edge to A LErising edge) 320 ns - - 9 ns Note 1: Timing with RDY. If RDY not used, tpw1 becomes 180 ns. Revision 1.06/October 2002 Semtech Corp. 68 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Serial Mode In Serial mode, the device is configured to interface with a serial microprocessor bus.The combined minimum High and Low times for SCLK define the maximum clock rate. For Write access this is 2.77 MHz (360 ns). For Read access the maximum SCLK rate is slightly slower and is affected by the setting of CLKE, being either 2.0 MHz (500 ns) or 1 MHz (1 us). This mismatch in rates is caused by the sampling technique used to detect the end of the address field in Read mode. It takes up to 3 cycles of an internal 6.40 MHz clock to start the Read process following receipt of the final address bit. This is 468 ns. The Read data is then decoded and clocked out onto SDO directly using SCLK. With CLKE=1, the falling edge of SCLK is used to clock out the SDO. With CLKE=0, the rising edge of SCLK is used to clock out the SDO. A minimum period of 500 ns (468 capture plus 32 decode) is required between the final address bit and clocking it out onto SDO. This means that to guarantee the correct operation of the Serial interface, with CLKE=0, SCLK has a maximum clock rate of 2 MHz. With CLKE=1, SCLK has a maximum clock rate of 1 MHz. SCLK is not required to run between accesses (i.e., when CSB = 1). The following Figures show the timing diagrams for Write and Read access for this mode. Figure 25. Read Access Timing in Serial Mode CLKE = 0; SDO data is clocked out on the rising edge of SCLK CSB tsu2 tpw2 th2 SCLK th1 tsu1 tpw1 _ SDI R/W A0 A1 A2 A3 A4 A5 A6 td1 SDO Output not driven, pulled low by internal resistor td2 D0 D1 D2 D3 D4 D5 D6 D7 CLKE = 1; SDO data is clocked out on the falling edge of SCLK CSB th2 SCLK _ SDI R/W A0 A1 A2 A3 A4 A5 A6 td1 SDO Output not driven, pulled low by internal resistor td2 D0 D1 D2 D3 D4 D5 D6 D7 F8525D_013ReadAccSerial_01 Revision 1.06/October 2002 Semtech Corp. 69 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 38. Read Access Timing in SERIAL Mode (for use with Figure 25) S y m b ol P ar am e t e r Setup SDI valid to SCLKrising edge tsu1 tsu2 Setup CSB falling edge to SCLKrising edge MIN T YP MA X 0 ns - - 160 ns - - td1 Delay SCLKrising edge ( SCLKfalling edge for CLKE = 1) to SDO valid - - 17 ns td 2 Delay CSB rising edge to SDO h igh -Z - - 10 ns tp w 1 SCLK low time CLKE = 0 CLKE = 1 250ns 500ns - - tp w 2 SCLK h igh time CLKE = 0 CLKE = 1 250ns 500ns - - th 1 Hold SDI valid after SCLKrising edge 170 ns - - th2 Hold CSB low after SCLKrising edge, for CLKE = 0 Hold CSB low after SCLKfalling edge, for CLKE = 1 5 ns - - tp Time b etw een consecutive accesses ( CSB rising edge to CSB falling edge) 160 ns - - Figure 26. Write Access Timing in SERIAL Mode CSB tsu2 tpw2 th2 ALE=SCLK th1 tsu1 tpw1 _ A(0)=SDI AD(0)=SDO R/W A0 A1 A2 A3 A4 A5 A6 D0 D1 D2 D3 D4 D5 D6 D7 Output not driven, pulled low by internal resistor F8110D_014WriteAccSerial_02 Table 39. Write Access Timing in SERIAL Mode (for use with Figure 26) S y m b ol P ar am e t e r MIN T YP MA X 0 ns - - tsu1 Setup SDI valid to SCLKrising edge tsu2 Setup CSBfalling edge to SCLKrising edge 160 ns - - tpw 1 SCLK low time 180 ns - - tp w 2 SCLK high time 180 ns - - th 1 Hold SDI valid after SCLKrising edge 170 ns - - th2 Hold CSB low after SCLKrising edge 5 ns - - tp Time b etw een consecutive accesses (CSBrising edge to CSBfalling edge) 160 ns - - Revision 1.06/October 2002 Semtech Corp. 70 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS EPROM Mode In EPROM mode, the ACS8510 takes control of the bus as Master, and reads the device set-up from an AMD AM27C64 type EPROM at lowest speed (250ns), after device start-up (system reset). The EPROM access state machine in the up interface sequences the accesses. Further details can be found in the AMD AM27C64 data sheet. Figure 27. Access Timing in EPROM Mode CSB (=OEB) A address t acc AD Z Z data Table 40. Access Timing in EPROM Mode (for use with Figure 27) S y m b ol tacc P ar am e t e r Delay CSBfalling edge or A ch ange to A D valid Revision 1.06/October 2002 Semtech Corp. 71 MIN T YP MA X - - 920 ns www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Package Information Figure 28. LQFP Package D 2 D1 1 3 AN2 AN3 1 Section A-A R1 S E 2 R2 B AN1 E1 1 A A B 3 AN4 L 4 L1 5 1 2 3 b Section B-B 7 e A A2 c c1 7 7 Seating plane A1 6 b1 7 b 8 Notes 1 The top package body may be smaller than the bottom package body by as much as 0.15 mm. 2 To be determined at seating plane. 3 Dimensions D1 and E1 do not include mold protrusion. Allowable protrusion is 0.25 mm per side. D1 and E1 are maximum plastic body size dimensions including mold mismatch. 4 Details of pin 1 identifier are optional but will be located within the zone indicated. 5 Exact shape of corners can vary. 6 A1 is defined as the distance from the seating plane to the lowest point of the package body. 7 These dimensions apply to the flat section of the lead between 0.10 mm and 0.25 mm from the lead tip. 8 Shows plating. Revision 1.06/October 2002 Semtech Corp. 72 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Table 41. 100 Pin LQFP Package Dimension Data (for use with Figure 28) 100 L Q F P P ac k ag e D i m e n si o n s in mm D/E D 1/ E 1 Mi n N om Max 16.00 14.00 A A1 A2 1.40 0.05 1.35 1.50 0.10 1.40 1.60 0.15 1.45 e 0.50 AN1 AN2 AN3 AN4 R1 R2 L 11° 11° 0° 0° 0.08 0.08 0.45 12° 12° - 3.5° - - 0.60 13° 13° - 7° - 0.20 0.75 L1 1.00 (ref) S b b1 c c1 0.20 0.17 0.17 0.09 0.09 - 0.22 0.20 - - - 0.27 0.23 0.20 0.16 Thermal Conditions The device is rated for full temperature range when this package is used with a 4 layer or more PCB. Copper coverage must exceed 50%. All pins must be soldered to the PCB. Maximum operating temperature must be reduced when the device is used with a PCB with less than these requirements. Figure 29. Typical 100 Pin LQFP Footprint 18.3 mm 17.0 mm (1) 14.6 mm 1.85 mm Pitch 0.5 mm Width 0.3 mm Notes (1) Solderable to this limit. Square package - dimensions apply in both X and Y directions. Typical example. The user is reponsible for ensuring compatibility with PCB manufacturing process, etc. Revision 1.06/October 2002 Semtech Corp. 73 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Application Information Figure 30. Simplified Application Schematic Revision 1.06/October 2002 Semtech Corp. 74 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Revision History Table 42. Changes from Revision 1.05 to 1.06 October 2002 I t em 1 S e ct i o n Serial Mode P ag e 69 Revision 1.06/October 2002 Semtech Corp. D e scr i p t i o n Up dated descrip tion of SCLK 75 www.semtech.com ACS8510 Rev2.1 SETS FINAL ADVANCED COMMUNICATIONS Ordering Information PA R T N U M B E R DE SCR I P T I O N A CS8510 Rev2.1 SON ET/SDH Synch ronisation, 100 p in LQFP Disclaimers Life support - This product is not designed or intended for use in life suport equipment, devices or systems, or other critical applications. This product is not authorized or warranted by Semtech Corporation for such use. Right to change - Semtech Corporation reserves the right to make changes, without notice, to this product. Customers are advised to obtain the latest version of the relevant information before placing orders. Compliance to relevant standards - Operation of this device is subject to the users implementation, and design practices. The user is responsible to ensure equipment using this device is compliant to any relevant standards. For additional information, contact the following: Semtech Corporation Advanced Communications Products E-Mail: [email protected] [email protected] Internet: http://www.semtech.com USA: Mailing Address: P.O. Box 6097, Camarillo, CA 93011-6097 Street Address: 200 Flynn Road, Camarillo, CA 93012-8790 Tel: +1 805 498 2111, Fax: +1 805 498 3804 FAR EAST: 11F, No. 46, Lane 11, Kuang Fu North Road, Taipei, Taiwan, R.O.C. Tel: +886 2 2748 3380, Fax: +886 2 2748 3390 EUROPE: Units 2 & 3 Park Court, Premier Way, Abbey Park Industrial Estate, Romsey, Hampshire, SO51 9DN, UK Tel: +44 1794 527 600, Fax: +44 1794 527 601 ISO9001 CERTIFIED Revision 1.06/October 2002 Semtech Corp. 76 www.semtech.com