CS2200-CP Fractional-N Frequency Synthesizer Features General Description Delta-Sigma Fractional-N Frequency Synthesis – Generates a Low Jitter 6 - 75 MHz Clock from an 8 - 75 MHz Reference Clock Highly Accurate PLL Multiplication Factor – Maximum Error Less Than 1 PPM I²C® / SPI™ Control Port Configurable Auxiliary Output – Buffered Reference Clock – PLL Lock Indication – Duplicate PLL Output Flexible Sourcing of Reference Clock – External Oscillator or Clock Source – Supports Inexpensive Local Crystal Minimal Board Space Required – No External Analog Loop-filter Components The CS2200-CP is an extremely versatile system clocking device that utilizes a programmable phase lock loop. The CS2200-CP is based on an analog PLL architecture comprised of a Delta-Sigma Fractional-N Frequency Synthesizer. This architecture allows for frequency synthesis and clock generation from a stable reference clock. The CS2200-CP supports both I²C and SPI for full software control. The CS2200-CP is available in a 10-pin MSOP package in Commercial (-10 °C to +70 °C) grade. Customer development kits are also available for device evaluation. Please see “Ordering Information” on page 25 for complete details. 3.3 V Timing Reference I²C/SPI Software Control PLL Output I²C / SPI PLL Lock Indicator 8 MHz to 75 MHz Low-Jitter Timing Reference Phase Comparator Internal Loop Filter Voltage Controlled Oscillator Auxiliary Output 6 to 75 MHz PLL Output Fractional-N Divider Delta-Sigma Modulator N Output to Input Clock Ratio Preliminary Product Information http://www.cirrus.com This document contains information for a new product. Cirrus Logic reserves the right to modify this product without notice. Copyright © Cirrus Logic, Inc. 2008 (All Rights Reserved) JUN '08 DS759PP1 CS2200-CP TABLE OF CONTENTS 1. PIN DESCRIPTION ................................................................................................................................. 4 2. TYPICAL CONNECTION DIAGRAM ..................................................................................................... 5 3. CHARACTERISTICS AND SPECIFICATIONS ...................................................................................... 6 RECOMMENDED OPERATING CONDITIONS .................................................................................... 6 ABSOLUTE MAXIMUM RATINGS ........................................................................................................ 6 DC ELECTRICAL CHARACTERISTICS ................................................................................................ 6 AC ELECTRICAL CHARACTERISTICS ................................................................................................ 7 CONTROL PORT SWITCHING CHARACTERISTICS- I²C FORMAT ................................................... 8 CONTROL PORT SWITCHING CHARACTERISTICS - SPI FORMAT ................................................. 9 4. ARCHITECTURE OVERVIEW ............................................................................................................. 10 4.1 Delta-Sigma Fractional-N Frequency Synthesizer ......................................................................... 10 5. APPLICATIONS ................................................................................................................................... 11 5.1 Timing Reference Clock Input ........................................................................................................ 11 5.1.1 Internal Timing Reference Clock Divider ............................................................................... 11 5.1.2 Crystal Connections (XTI and XTO) ...................................................................................... 11 5.1.3 External Reference Clock (REF_CLK) .................................................................................. 12 5.2 Output to Input Frequency Ratio Configuration ............................................................................. 12 5.2.1 User Defined Ratio (RUD) ..................................................................................................... 12 5.2.2 Manual Ratio Modifier (R-Mod) ............................................................................................. 12 5.2.3 Effective Ratio (REFF) .......................................................................................................... 13 5.2.4 Ratio Configuration Summary ............................................................................................... 13 5.3 PLL Clock Output ........................................................................................................................... 14 5.4 Auxiliary Output .............................................................................................................................. 14 5.5 Clock Output Stability Considerations ............................................................................................ 15 5.5.1 Output Switching ................................................................................................................... 15 5.5.2 PLL Unlock Conditions .......................................................................................................... 15 6. SPI / I²C CONTROL PORT ................................................................................................................... 16 6.1 SPI Control ..................................................................................................................................... 16 6.2 I²C Control ...................................................................................................................................... 16 6.3 Memory Address Pointer ............................................................................................................... 18 6.3.1 Map Auto Increment .............................................................................................................. 18 7. REGISTER QUICK REFERENCE ........................................................................................................ 18 8. REGISTER DESCRIPTIONS ................................................................................................................ 19 8.1 Device I.D. and Revision (Address 01h) ....................................................................................... 19 8.1.1 Device Identification (Device[4:0]) - Read Only ..................................................................... 19 8.1.2 Device Revision (Revision[2:0]) - Read Only ........................................................................ 19 8.2 Device Control (Address 02h) ........................................................................................................ 19 8.2.1 Unlock Indicator (Unlock) - Read Only .................................................................................. 19 8.2.2 Auxiliary Output Disable (AuxOutDis) ................................................................................... 19 8.2.3 PLL Clock Output Disable (ClkOutDis) .................................................................................. 20 8.3 Device Configuration 1 (Address 03h) ........................................................................................... 20 8.3.1 R-Mod Selection (RModSel[2:0]) ........................................................................................... 20 8.3.2 Auxiliary Output Source Selection (AuxOutSrc[1:0]) ............................................................. 20 8.3.3 Enable Device Configuration Registers 1 (EnDevCfg1) ........................................................ 20 8.4 Global Configuration (Address 05h) ............................................................................................... 21 8.4.1 Device Configuration Freeze (Freeze) ................................................................................ 21 8.4.2 Enable Device Configuration Registers 2 (EnDevCfg2) ....................................................... 21 8.5 Ratio (Address 06h - 09h) .............................................................................................................. 21 8.6 Function Configuration 1 (Address 16h) ........................................................................................ 22 8.6.1 AUX PLL Lock Output Configuration (AuxLockCfg) .............................................................. 22 8.6.2 Reference Clock Input Divider (RefClkDiv[1:0]) .................................................................... 22 8.7 Function Configuration 2 (Address 17h) ........................................................................................ 22 2 DS759PP1 CS2200-CP 8.7.1 Enable PLL Clock Output on Unlock (ClkOutUnl) ................................................................. 22 9. CALCULATING THE USER DEFINED RATIO .................................................................................... 23 9.1 12.20 Format .................................................................................................................................. 23 10. PACKAGE DIMENSIONS .................................................................................................................. 24 THERMAL CHARACTERISTICS ......................................................................................................... 24 11. ORDERING INFORMATION .............................................................................................................. 25 12. REFERENCES .................................................................................................................................... 25 13. REVISION HISTORY .......................................................................................................................... 25 LIST OF FIGURES Figure 1. Typical Connection Diagram ........................................................................................................ 5 Figure 2. Control Port Timing - I²C Format .................................................................................................. 8 Figure 3. Control Port Timing - SPI Format (Write Only) ............................................................................ 9 Figure 4. Delta-Sigma Fractional-N Frequency Synthesizer ..................................................................... 10 Figure 5. Internal Timing Reference Clock Divider ................................................................................... 11 Figure 6. External Component Requirements for Crystal Circuit .............................................................. 11 Figure 7. Ratio Feature Summary ............................................................................................................. 13 Figure 8. PLL Clock Output Options ......................................................................................................... 14 Figure 9. Auxiliary Output Selection .......................................................................................................... 14 Figure 10. Control Port Timing in SPI Mode ............................................................................................. 16 Figure 11. Control Port Timing, I²C Write .................................................................................................. 17 Figure 12. Control Port Timing, I²C Aborted Write + Read ....................................................................... 17 LIST OF TABLES Table 1. Ratio Modifier .............................................................................................................................. 12 Table 2. Example 12.20 R-Values ............................................................................................................ 23 DS759PP1 3 CS2200-CP 1. PIN DESCRIPTION VD 1 10 SDA/CDIN GND 2 9 SCL/CCLK CLK_OUT 3 8 AD0/CS AUX_OUT 4 7 XTI/REF_CLK TST_IN 5 6 XTO Pin Name # Pin Description VD 1 Digital Power (Input) - Positive power supply for the digital and analog sections. GND 2 Ground (Input) - Ground reference. CLK_OUT 3 PLL Clock Output (Output) - PLL clock output. 4 Auxiliary Output (Output) - This pin outputs a buffered version of one of the input or output clocks, or a status signal, depending on register configuration. 5 Test Input (Input) - This pin is for factory test purposes and must be connected to GND for proper operation. 6 7 Crystal Connections (XTI/XTO) / Timing Reference Clock Input (REF_CLK) (Input/Output) XTI/XTO are I/O pins for an external crystal which may be used to generate the low-jitter PLL input clock. REF_CLK is an input for an externally generated low-jitter reference clock. 8 Address Bit 0 (I²C) / Control Port Chip Select (SPI) (Input) - AD0 is a chip address pin in I²C Mode. CS is the chip select signal in SPI Mode. 9 Control Port Clock (Input) - SCL/CCLK is the serial clock for the serial control port in I²C and SPI mode. AUX_OUT TST_IN XTO XTI/REF_CLK AD0/CS SCL/CCLK SDA/CDIN 4 10 Serial Control Data (Input/Output) - SDA is the data I/O line in I²C Mode. CDIN is the input data line for the control port interface in SPI Mode. DS759PP1 CS2200-CP 2. TYPICAL CONNECTION DIAGRAM Note1 Notes: 1. Resistors required for I2C operation. 0.1 µF 2 kΩ 1 µF +3.3 V 2 kΩ VD SCL/CCLK System MicroController SDA/CDIN CLK_OUT AD0/CS To circuitry which requires a low-jitter clock CS2200-CP AUX_OUT 1 or 2 XTI/REF_CLK XTO GND Low-Jitter Timing Reference To other circuitry or Microcontroller TST_IN REF_CLK 1 N.C. x XTO or Crystal XTI 2 XTO 40 pF 40 pF Figure 1. Typical Connection Diagram DS759PP1 5 CS2200-CP 3. CHARACTERISTICS AND SPECIFICATIONS RECOMMENDED OPERATING CONDITIONS GND = 0 V; all voltages with respect to ground. (Note 1) Parameters DC Power Supply Symbol Min Typ Max Units VD 3.1 3.3 3.5 V TAC -10 - +70 °C Ambient Operating Temperature (Power Applied) Commercial Grade Notes: 1. Device functional operation is guaranteed within these limits. Functionality is not guaranteed or implied outside of these limits. Operation outside of these limits may adversely affect device reliability. ABSOLUTE MAXIMUM RATINGS GND = 0 V; all voltages with respect to ground. Parameters Symbol Min Max Units DC Power Supply VD -0.3 6.0 V Input Current IIN - ±10 mA Digital Input Voltage (Note 1) VIN -0.3 VD + 0.4 V Ambient Operating Temperature (Power Applied) TA -55 125 °C Storage Temperature Tstg -65 150 °C WARNING: Operation at or beyond these limits may result in permanent damage to the device. Notes: 1. The maximum over/under voltage is limited by the input current except on the power supply pin. DC ELECTRICAL CHARACTERISTICS Test Conditions (unless otherwise specified): VD = 3.1 V to 3.5 V; TA = -10°C to +70°C (Commercial Grade). Parameters Symbol Min Typ Max Units Power Supply Current - Unloaded (Note 2) ID - 12 18 mA Power Dissipation - Unloaded (Note 2) PD - 40 60 mW Input Leakage Current IIN - - ±10 µA Input Capacitance IC - 8 - pF High-Level Input Voltage VIH 70% - - VD Low-Level Input Voltage VIL - - 30% VD High-Level Output Voltage (IOH = -1.2 mA) VOH 80% - - VD Low-Level Output Voltage (IOH = 1.2 mA) VOL - - 20% VD Notes: 2. To calculate the additional current consumption due to loading (per output pin), multiply clock output frequency by load capacitance and power supply voltage. For example, fCLK_OUT (49.152 MHz) * CL (15 pF) * VD (3.3 V) = 2.4 mA of additional current due to these loading conditions on CLK_OUT. 6 DS759PP1 CS2200-CP AC ELECTRICAL CHARACTERISTICS Test Conditions (unless otherwise specified): VD = 3.1 V to 3.5 V; TA = -10°C to +70°C (Commercial Grade); CL = 15 pF. Parameters Crystal Frequency Symbol Conditions Min Typ Max Units fXTAL Fundamental Mode 8 - 50 MHz Reference Clock Input Frequency fREF_CLK 8 - 75 MHz Reference Clock Input Duty Cycle DREF_CLK 45 - 55 % Internal System Clock Frequency fSYS_CLK 8 18.75 MHz PLL Clock Output Frequency fCLK_OUT 6 75 MHz - PLL Clock Output Duty Cycle tOD Measured at VD/2 48 50 52 % Clock Output Rise Time tOR 20% to 80% of VD - 1.7 3.0 ns Clock Output Fall Time tOF 80% to 20% of VD - 1.7 3.0 ns Period Jitter tJIT (Note 3) - 70 150 ps rms Base Band Jitter (100 Hz to 40 kHz) (Notes 3, 4) - 50 - ps rms Wide Band JItter (100 Hz Corner) (Notes 3, 5) - 175 - ps rms - 1 2 ms 0 - ±0.5 ppm PLL Lock Time - REF_CLK tLR Output Frequency Synthesis Resolution (Note 6) ferr fREF_CLK = 8 to 75 MHz Notes: 3. fCLK_OUT = 24.576 MHz; Sample size = 10,000 points; AuxOutSrc[1:0] = 11. 4. In accordance with AES-12id-2006 section 3.4.2. Measurements are Time Interval Error taken with 3rd order 100 Hz to 40 kHz bandpass filter. 5. In accordance with AES-12id-2006 section 3.4.1. Measurements are Time Interval Error taken with 3rd order 100 Hz Highpass filter. 6. The frequency accuracy of the PLL clock output is directly proportional to the frequency accuracy of the reference clock. DS759PP1 7 CS2200-CP CONTROL PORT SWITCHING CHARACTERISTICS- I²C FORMAT Inputs: Logic 0 = GND; Logic 1 = VD; CL = 20 pF. Parameter Symbol Min Max Unit SCL Clock Frequency fscl - 100 kHz Bus Free-Time Between Transmissions tbuf 4.7 - µs Start Condition Hold Time (prior to first clock pulse) thdst 4.0 - µs Clock Low Time tlow 4.7 - µs Clock High Time thigh 4.0 - µs Setup Time for Repeated Start Condition tsust 4.7 - µs SDA Hold Time from SCL Falling (Note 7) thdd 0 - µs tsud 250 - ns Rise Time of SCL and SDA tr - 1 µs Fall Time SCL and SDA tf - 300 ns SDA Setup Time to SCL Rising Setup Time for Stop Condition tsusp 4.7 - µs Acknowledge Delay from SCL Falling tack 300 1000 ns Delay from Supply Voltage Stable to Control Port Ready tdpor 100 - µs Notes: 7. Data must be held for sufficient time to bridge the transition time, tf, of SCL. VD t dpor Repeated Start Stop SDA t buf t t high t hdst tf hdst t susp SCL Stop Start t low t hdd t sud t sust tr Figure 2. Control Port Timing - I²C Format 8 DS759PP1 CS2200-CP CONTROL PORT SWITCHING CHARACTERISTICS - SPI FORMAT Inputs: Logic 0 = GND; Logic 1 = VD; CL = 20 pF. Parameter Symbol Min Max Unit fccllk - 6 MHz tspi 500 - ns CS High Time Between Transmissions tcsh 1.0 - µs CS Falling to CCLK Edge tcss 20 - ns CCLK Low Time tscl 66 - ns CCLK High Time tsch 66 - ns CCLK Clock Frequency CCLK Edge to CS Falling (Note 8) CDIN to CCLK Rising Setup Time tdsu 40 - ns (Note 9) tdh 15 - ns Rise Time of CCLK and CDIN (Note 10) tr2 - 100 ns Fall Time of CCLK and CDIN (Note 10) tf2 - 100 ns tdpor 100 - µs CCLK Rising to DATA Hold Time Delay from Supply Voltage Stable to Control Port Ready Notes: 8. tspi is only needed before first falling edge of CS after power is applied. tspi = 0 at all other times. 9. Data must be held for sufficient time to bridge the transition time of CCLK. 10. For fcclk < 1 MHz. VD tdpor CS t spi t css t scl t sch t csh CCLK t r2 t f2 CDIN t dsu tdh Figure 3. Control Port Timing - SPI Format (Write Only) DS759PP1 9 CS2200-CP 4. ARCHITECTURE OVERVIEW 4.1 Delta-Sigma Fractional-N Frequency Synthesizer The core of the CS2200 is a Delta-Sigma Fractional-N Frequency Synthesizer which has very high-resolution for Input/Output clock ratios, low phase noise, very wide range of output frequencies and the ability to quickly tune to a new frequency. In very simplistic terms, the Fractional-N Frequency Synthesizer multiplies the Timing Reference Clock by the value of N to generate the PLL output clock. The desired output to input clock ratio is the value of N that is applied to the delta-sigma modulator (see Figure 4). The analog PLL based frequency synthesizer uses a low-jitter timing reference clock as a time and phase reference for the internal voltage controlled oscillator (VCO). The phase comparator compares the fractional-N divided clock with the original timing reference and generates a control signal. The control signal is filtered by the internal loop filter to generate the VCO’s control voltage which sets its output frequency. The delta-sigma modulator modulates the loop integer divide ratio to get the desired fractional ratio between the reference clock and the VCO output (thus the one’s density of the modulator sets the fractional value). This allows the design to be optimized for very fast lock times for a wide range of output frequencies without the need for external filter components. As with any Fractional-N Frequency Synthesizer the timing reference clock should be stable and jitter-free. Timing Reference Clock Phase Comparator Internal Loop Filter Voltage Controlled Oscillator PLL Output Fractional-N Divider Delta-Sigma Modulator N Figure 4. Delta-Sigma Fractional-N Frequency Synthesizer 10 DS759PP1 CS2200-CP 5. APPLICATIONS 5.1 Timing Reference Clock Input The low jitter timing reference clock (RefClk) can be provided by either an external reference clock or an external crystal in conjunction with the internal oscillator. In order to maintain a stable and low-jitter PLL output the timing reference clock must also be stable and low-jitter; the quality of the timing reference clock directly affects the performance of the PLL and hence the quality of the PLL output. 5.1.1 Internal Timing Reference Clock Divider The Internal Timing Reference Clock (SysClk) has a smaller maximum frequency than what is allowed on the XTI/REF_CLK pin. The CS2200 supports the wider external frequency range by offering an internal divider for RefClk. The RefClkDiv[1:0] bits should be set such that SysClk, the divided RefClk, then falls within the valid range as indicated in Figure 5. Timing Reference Clock XTI/REF_CLK 8 MHz < RefClk < 50 MHz (XTI) 75 MHz (REF_CLK) Timing Reference Clock Divider ÷1 ÷2 ÷4 Internal Timing Reference Clock 8 MHz < SysClk < 18.75 MHz Fractional-N Frequency Synthesizer PLL Output N RefClkDiv[1:0] Figure 5. Internal Timing Reference Clock Divider It should be noted that the maximum allowable input frequency of the XTI/REF_CLK pin is dependent upon its configuration as either a crystal connection or external clock input. See the “AC Electrical Characteristics” on page 7 for more details. Referenced Control Register Location RefClkDiv[1:0] .......................“Reference Clock Input Divider (RefClkDiv[1:0])” on page 22 5.1.2 Crystal Connections (XTI and XTO) An external crystal may be used to generate RefClk. To accomplish this, a 20 pF fundamental mode parallel resonant crystal must be connected between the XTI and XTO pins as shown in Figure 6. As shown, nothing other than the crystal and its load capacitors should be connected to XTI and XTO. Please refer to the “AC Electrical Characteristics” on page 7 for the allowed crystal frequency range. XTI 40 pF XTO 40 pF Figure 6. External Component Requirements for Crystal Circuit DS759PP1 11 CS2200-CP 5.1.3 External Reference Clock (REF_CLK) For operation with an externally generated REF_CLK signal, XTI/REF_CLK should be connected to the reference clock source and XTO should be left unconnected or pulled low through a 47 kΩ resistor to GND. 5.2 5.2.1 Output to Input Frequency Ratio Configuration User Defined Ratio (RUD) The User Defined Ratio, RUD, is a 32-bit un-signed fixed-point number, stored in the Ratio register set, which determines the basis for the desired input to output clock ratio. The 32-bit RUD is represented in a 12.20 format where the 12 MSBs represent the integer binary portion while the remaining 20 LSBs represent the fractional binary portion. The maximum multiplication factor is approximately 4096 with a resolution of 0.954 PPM in this configuration. See “Calculating the User Defined Ratio” on page 23 for more information. The status of internal dividers, such as the internal timing reference clock divider, are automatically taken into account. Therefore RUD is simply the desired ratio of the output to input clock frequencies. Referenced Control Register Location Ratio......................................“Ratio (Address 06h - 09h)” on page 21 5.2.2 Manual Ratio Modifier (R-Mod) The manual Ratio Modifier is used to internally multiply/divide the RUD (the Ratio stored in the register space remains unchanged). The available options for RMOD are summarized in Table 1 on page 12. The R-Mod value selected by RModSel[2:0] is always used in the calculation for the Effective Ratio (REFF), see “Effective Ratio (REFF)” on page 13. If R-Mod is not desired, RModSel[2:0] should be left at its default value of ‘000’, which corresponds to an R-Mod value of 1, thereby effectively disabling the ratio modifier. RModSel[2:0] Ratio Modifier 000 1 001 2 010 4 011 8 100 0.5 101 0.25 110 0.125 111 0.0625 Table 1. Ratio Modifier Referenced Control Register Location Ratio......................................“Ratio (Address 06h - 09h)” on page 21 RModSel[2:0] ........................“R-Mod Selection (RModSel[2:0])” section on page 20 12 DS759PP1 CS2200-CP 5.2.3 Effective Ratio (REFF) The Effective Ratio (REFF) is an internal calculation comprised of RUD and the appropriate modifiers, as previously described. REFF is calculated as follows: REFF = RUD • RMOD To simplify operation the device handles some of the ratio calculation functions automatically (such as when the internal timing reference clock divider is set). For this reason, the Effective Ratio does not need to be altered to account for internal dividers. Ratio modifiers which would produce an overflow or truncation of REFF should not be used; For example if RUD is 1024 an RMOD of 8 would produce an REFF value of 8192 which exceeds the 4096 limit of the 12.20 format. In all cases, the maximum and minimum allowable values for REFF are dictated by the frequency limits for both the input and output clocks as shown in the “AC Electrical Characteristics” on page 7. 5.2.4 Ratio Configuration Summary The RUD is the user defined ratio stored in the register space. R-Mod is applied if selected. The user defined ratio and ratio modifier make up the effective ratio REFF, the final calculation used to determine the output to input clock ratio. The effective ratio is then corrected for the internal dividers. The conceptual diagram in Figure 7 summarizes the features involved in the calculation of the ratio values used to generate the fractional-N value which controls the Frequency Synthesizer. Timing Reference Clock (XTI/REF_CLK) Divide RefClkDiv[1:0] Effective Ratio REFF SysClk User Defined Ratio RUD Ratio Ratio Format 12.20 RModSel[2:0] RefClkDiv[1:0] Ratio Modifier R Correction Frequency Synthesizer PLL Outpu N Figure 7. Ratio Feature Summary Referenced Control Register Location Ratio......................................“Ratio (Address 06h - 09h)” on page 21 RModSel[2:0] ........................“R-Mod Selection (RModSel[2:0])” section on page 20 RefClkDiv[1:0] .......................“Reference Clock Input Divider (RefClkDiv[1:0])” on page 22 DS759PP1 13 CS2200-CP 5.3 PLL Clock Output The PLL clock output pin (CLK_OUT) provides a buffered version of the output of the frequency synthesizer. The driver can be set to high-impedance with the ClkOutDis bit. The output from the PLL automatically drives a static low condition while the PLL is un-locked (when the clock may be unreliable). This feature can be disabled by setting the ClkOutUnl bit, however the state CLK_OUT may then be unreliable during an unlock condition. ClkOutUnl PLL Locked/Unlocked 0 0 2:1 Mux ClkOutDis 0 1 2:1 Mux PLL Clock Output PLL Clock Output Pin (CLK_OUT) PLLClkOut 1 PLL Output Figure 8. PLL Clock Output Options Referenced Control Register Location ClkOutUnl..............................“Enable PLL Clock Output on Unlock (ClkOutUnl)” on page 22 ClkOutDis ..............................“PLL Clock Output Disable (ClkOutDis)” on page 20 5.4 Auxiliary Output The auxiliary output pin (AUX_OUT) can be mapped, as shown in Figure 9, to one of three signals: reference clock (RefClk), additional PLL clock output (CLK_OUT), or a PLL lock indicator (Lock). The mux is controlled via the AuxOutSrc[1:0] bits. If AUX_OUT is set to Lock, the AuxLockCfg bit is then used to control the output driver type and polarity of the LOCK signal (see section 8.6.1 on page 22). If AUX_OUT is set to CLK_OUT the phase of the PLL Clock Output signal on AUX_OUT may differ from the CLK_OUT pin. The driver for the pin can be set to high-impedance using the AuxOutDis bit. AuxOutSrc[1:0] Timing Reference Clock (RefClk) PLL Clock Output (PLLClkOut) PLL Lock/Unlock Indication (Lock) AuxOutDis Auxiliary Output Pin (AUX_OUT) 3:1 Mux AuxLockCfg Figure 9. Auxiliary Output Selection Referenced Control Register Location AuxOutSrc[1:0]......................“Auxiliary Output Source Selection (AuxOutSrc[1:0])” on page 20 AuxOutDis .............................“Auxiliary Output Disable (AuxOutDis)” on page 19 AuxLockCfg...........................“AUX PLL Lock Output Configuration (AuxLockCfg)” section on page 22 14 DS759PP1 CS2200-CP 5.5 5.5.1 Clock Output Stability Considerations Output Switching CS2200 is designed such that re-configuration of the clock routing functions do not result in a partial clock period on any of the active outputs (CLK_OUT and/or AUX_OUT). In particular, enabling or disabling an output, changing the auxiliary output source between REF_CLK and CLK_OUT, and the automatic disabling of the output(s) during unlock will not cause a runt or partial clock period. The following exceptions/limitations exist: • Enabling/disabling AUX_OUT when AuxOutSrc = 11 (unlock indicator). • Switching AuxOutSrc[1:0] to or from 11 (unlock indicator) (Transitions between AuxOutSrc[1:0] = [00,10] will not produce a glitch). • Changing the ClkOutUnl bit while the PLL is in operation. When any of these exceptions occur, a partial clock period on the output may result. 5.5.2 PLL Unlock Conditions Certain changes to the clock inputs and registers can cause the PLL to lose lock which will affect the presence the clock signal on CLK_OUT. The following outlines which conditions cause the PLL to go unlocked: • Changes made to the registers which affect the Fraction-N value that is used by the Frequency Synthesizer. This includes all the bits shown in Figure 7 on page 13. • Any discontinuities on the Timing Reference Clock, REF_CLK. DS759PP1 15 CS2200-CP 6. SPI / I²C CONTROL PORT The control port is used to access the registers and allows the device to be configured for the desired operational modes and formats. The operation of the control port may be completely asynchronous with respect to device inputs and outputs. However, to avoid potential interference problems, the control port pins should remain static if no operation is required. The control port operates with either the SPI or I²C interface, with the CS2200 acting as a slave device. SPI Mode is selected if there is a high-to-low transition on the AD0/CS pin after power-up. I²C Mode is selected by connecting the AD0/CS pin through a resistor to VD or GND, thereby permanently selecting the desired AD0 bit address state. In both modes the EnDevCfg1 and EnDevCfg2 bits must be set to 1 for normal operation. WARNING: All “Reserved” registers must maintain their default state to ensure proper functional operation. Referenced Control Register Location EnDevCfg1 ............................“Enable Device Configuration Registers 1 (EnDevCfg1)” on page 20 EnDevCfg2 ............................“Enable Device Configuration Registers 2 (EnDevCfg2)” section on page 21 6.1 SPI Control In SPI Mode, CS is the chip select signal; CCLK is the control port bit clock (sourced from a microcontroller), and CDIN is the input data line from the microcontroller. Data is clocked in on the rising edge of CCLK. The device only supports write operations. Figure 10 shows the operation of the control port in SPI Mode. To write to a register, bring CS low. The first eight bits on CDIN form the chip address and must be 10011110. The next eight bits form the Memory Address Pointer (MAP), which is set to the address of the register that is to be updated. The next eight bits are the data which will be placed into the register designated by the MAP. There is MAP auto increment capability, enabled by the INCR bit in the MAP register. If INCR is a zero, the MAP will stay constant for successive read or writes. If INCR is set to a 1, the MAP will automatically increment after each byte is read or written, allowing block writes of successive registers. CS 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 CCLK CHIP ADDRESS CDIN 1 0 0 1 1 1 MAP BYTE 1 0 INCR 6 5 4 3 2 DATA +n DATA 1 0 7 6 1 0 7 6 1 0 Figure 10. Control Port Timing in SPI Mode 6.2 I²C Control In I²C Mode, SDA is a bidirectional data line. Data is clocked into and out of the device by the clock, SCL. There is no CS pin. The AD0 pin forms the least-significant bit of the chip address and should be connected to VD or GND as appropriate. The state of the AD0 pin should be maintained throughout operation of the device. The signal timings for a read and write cycle are shown in Figure 11 and Figure 12. A Start condition is defined as a falling transition of SDA while the clock is high. A Stop condition is a rising transition while the clock is high. All other transitions of SDA occur while the clock is low. The first byte sent to the CS2200 after a Start condition consists of the 7-bit chip address field and a R/W bit (high for a read, low for a write). The upper 6 bits of the 7-bit address field are fixed at 100111 followed by the logic state of the AD0 pin. The 16 DS759PP1 CS2200-CP eighth bit of the address is the R/W bit. If the operation is a write, the next byte is the Memory Address Pointer (MAP) which selects the register to be read or written. If the operation is a read, the contents of the register pointed to by the MAP will be output. Setting the auto increment bit in MAP allows successive reads or writes of consecutive registers. Each byte is separated by an acknowledge bit. The ACK bit is output from the CS2200 after each input byte is read and is input from the microcontroller after each transmitted byte. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 24 25 26 27 28 SCL CHIP ADDRESS (WRITE) 1 SDA 0 0 1 1 1 AD0 MAP BYTE 0 INCR 6 5 4 3 2 1 0 ACK 7 6 DATA +n DATA +1 DATA 1 0 ACK 7 6 1 0 7 6 1 0 ACK ACK STOP START Figure 11. Control Port Timing, I²C Write 0 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 SCL CHIP ADDRESS (WRITE) SDA 1 0 0 1 STOP MAP BYTE 1 1 AD0 0 INCR 6 5 4 3 2 1 ACK START CHIP ADDRESS (READ) 1 0 0 ACK 0 1 0 DATA 1 AD0 1 7 ACK START DATA +1 0 7 ACK 0 DATA + n 7 0 NO ACK STOP Figure 12. Control Port Timing, I²C Aborted Write + Read Since the read operation cannot set the MAP, an aborted write operation is used as a preamble. As shown in Figure 11, the write operation is aborted after the acknowledge for the MAP byte by sending a stop condition. The following pseudocode illustrates an aborted write operation followed by a read operation. Send start condition. Send 100111x0 (chip address & write operation). Receive acknowledge bit. Send MAP byte, auto increment off. Receive acknowledge bit. Send stop condition, aborting write. Send start condition. Send 100111x1(chip address & read operation). Receive acknowledge bit. Receive byte, contents of selected register. Send acknowledge bit. Send stop condition. Setting the auto increment bit in the MAP allows successive reads or writes of consecutive registers. Each byte is separated by an acknowledge bit. DS759PP1 17 CS2200-CP 6.3 Memory Address Pointer The Memory Address Pointer (MAP) byte comes after the address byte and selects the register to be read or written. Refer to the pseudocode above for implementation details. 6.3.1 Map Auto Increment The device has MAP auto increment capability enabled by the INCR bit (the MSB) of the MAP. If INCR is set to 0, MAP will stay constant for successive I²C writes or reads and SPI writes. If INCR is set to 1, MAP will auto increment after each byte is read or written, allowing block reads or writes of successive registers. 7. REGISTER QUICK REFERENCE This table shows the register and bit names with their associated default values. EnDevCfg1 and EnDevCfg2 bits must be set to 1 for normal operation. WARNING: All “Reserved” registers must maintain their default state to ensure proper functional operation. Adr Name 01h Device ID p 19 02h Device Ctrl p 19 03h Device Cfg 1 p 20 05h Global Cfg p 21 06h - 32-Bit Ratio 09h 16h Funct Cfg 1 p 22 17h Funct Cfg 2 p 22 18 7 6 5 4 3 2 1 Device4 Device3 Device2 Device1 Device0 Revision2 Revision1 0 0 0 0 0 x x Unlock Reserved Reserved Reserved Reserved Reserved AuxOutDis x 0 0 0 0 0 0 RModSel2 RModSel1 RModSel0 Reserved Reserved AuxOutSrc1 AuxOutSrc0 0 0 0 0 0 0 0 Reserved Reserved Reserved Reserved Freeze Reserved Reserved 0 0 0 0 0 0 0 MSB ........................................................................................................................... MSB-8 ........................................................................................................................... LSB+15 ........................................................................................................................... LSB+7 ........................................................................................................................... Reserved AuxLockCfg Reserved RefClkDiv1 RefClkDiv0 Reserved Reserved 0 0 0 0 0 0 0 Reserved Reserved Reserved ClkOutUnl Reserved Reserved Reserved 0 0 0 0 0 0 0 0 Revision0 x ClkOutDis 0 EnDevCfg1 0 EnDevCfg2 0 MSB-7 MSB-15 LSB+8 LSB Reserved 0 Reserved 0 DS759PP1 CS2200-CP 8. REGISTER DESCRIPTIONS In I²C Mode all registers are read/write unless otherwise stated. In SPI mode all registers are write only. All “Reserved” registers must maintain their default state to ensure proper functional operation. The default state of each bit after a power-up sequence or reset is indicated by the shaded row in the bit decode table and in the “Register Quick Reference” on page 18. Control port mode is entered when the device recognizes a valid chip address input on its I²C/SPI serial control pins and the EnDevCfg1 and EnDevCfg2 bits are set to 1. 8.1 Device I.D. and Revision (Address 01h) 7 Device4 8.1.1 6 Device3 5 Device2 4 Device1 3 Device0 2 Revision2 1 Revision1 0 Revision0 2 Reserved 1 AuxOutDis 0 ClkOutDis Device Identification (Device[4:0]) - Read Only I.D. code for the CS2200. 8.1.2 Device[4:0] Device 00000 CS2200. Device Revision (Revision[2:0]) - Read Only CS2200 revision level. 8.2 REVID[2:0] Revision Level 100 B2. Device Control (Address 02h) 7 Unlock 8.2.1 6 Reserved 5 Reserved 4 Reserved 3 Reserved Unlock Indicator (Unlock) - Read Only Indicates the lock state of the PLL. 8.2.2 Unlock PLL Lock State 0 PLL is Locked. 1 PLL is Unlocked. Auxiliary Output Disable (AuxOutDis) This bit controls the output driver for the AUX_OUT pin. AuxOutDis Output Driver State 0 AUX_OUT output driver enabled. 1 AUX_OUT output driver set to high-impedance. Application: “Auxiliary Output” on page 14 DS759PP1 19 CS2200-CP 8.2.3 PLL Clock Output Disable (ClkOutDis) This bit controls the output driver for the CLK_OUT pin. 8.3 ClkOutDis Output Driver State 0 CLK_OUT output driver enabled. 1 CLK_OUT output driver set to high-impedance. Application: “PLL Clock Output” on page 14 Device Configuration 1 (Address 03h) 7 RModSel2 8.3.1 6 RModSel1 5 RModSel0 4 Reserved 3 Reserved 2 AuxOutSrc1 1 AuxOutSrc0 0 EnDevCfg1 R-Mod Selection (RModSel[2:0]) Selects the R-Mod value, which is used as a factor in determining the PLL’s Fractional N. 8.3.2 RModSel[2:0] R-Mod Selection 000 Left-shift R-value by 0 (x 1). 001 Left-shift R-value by 1 (x 2). 010 Left-shift R-value by 2 (x 4). 011 Left-shift R-value by 3 (x 8). 100 Right-shift R-value by 1 (÷ 2). 101 Right-shift R-value by 2 (÷ 4). 110 Right-shift R-value by 3 (÷ 8). 111 Right-shift R-value by 4 (÷ 16). Application: “Manual Ratio Modifier (R-Mod)” on page 12 Auxiliary Output Source Selection (AuxOutSrc[1:0]) Selects the source of the AUX_OUT signal. AuxOutSrc[1:0] Auxiliary Output Source 00 RefClk. 01 Reserved. 10 CLK_OUT. 11 PLL Lock Status Indicator. Application: “Auxiliary Output” on page 14 Note: When set to 11, AuxLckCfg sets the polarity and driver type (“AUX PLL Lock Output Configuration (AuxLockCfg)” on page 22). 8.3.3 Enable Device Configuration Registers 1 (EnDevCfg1) This bit, in conjunction with EnDevCfg2, enables control port mode. Both bits must be set to 1 during initialization. EnDevCfg1 Disabled. 1 Enabled. Application: “SPI / I²C Control Port” on page 16 Note: 20 Register State 0 EnDevCfg2 must also be set to enable control port mode (“SPI / I²C Control Port” on page 16). DS759PP1 CS2200-CP 8.4 Global Configuration (Address 05h) 7 Reserved 8.4.1 6 Reserved 5 Reserved 4 Reserved 3 Freeze 2 Reserved 1 Reserved 0 EnDevCfg2 Device Configuration Freeze (Freeze) Setting this bit allows writes to the Device Control and Device Configuration registers (address 02h - 04h) but keeps them from taking effect until this bit is cleared. 8.4.2 FREEZE Device Control and Configuration Registers 0 Register changes take effect immediately. 1 Modifications may be made to Device Control and Device Configuration registers (registers 02h-04h) without the changes taking effect until after the FREEZE bit is cleared. Enable Device Configuration Registers 2 (EnDevCfg2) This bit, in conjunction with EnDevCfg1, enables control port mode. Both bits must be set to 1 during initialization. EnDevCfg2 0 Disabled. 1 Enabled. Application: “SPI / I²C Control Port” on page 16 Note: 8.5 Register State EnDevCfg1 must also be set to enable control port mode (“SPI / I²C Control Port” on page 16). Ratio (Address 06h - 09h) 7 MSB MSB-8 LSB+15 LSB+7 6 5 4 3 2 1 ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... 0 MSB-7 MSB-15 LSB+8 LSB These registers contain the User Defined Ratio as shown in the “Register Quick Reference” section on page 18. These 4 registers form a single 32-bit ratio value as shown above. See “Output to Input Frequency Ratio Configuration” on page 12 and “Calculating the User Defined Ratio” on page 23 for more details. DS759PP1 21 CS2200-CP 8.6 Function Configuration 1 (Address 16h) 7 Reserved 8.6.1 6 AuxLockCfg 5 Reserved 4 RefClkDiv1 3 RefClkDiv0 2 Reserved 1 Reserved 0 Reserved AUX PLL Lock Output Configuration (AuxLockCfg) When the AUX_OUT pin is configured as a lock indicator (AuxOutSrc[1:0] = 11), this bit configures the AUX_OUT driver to either push-pull or open drain. It also determines the polarity of the lock signal. If AUX_OUT is configured as a clock output, the state of this bit is disregarded. AuxLockCfg AUX_OUT Driver Configuration 0 Push-Pull, Active High (output ‘high’ for unlocked condition, ‘low’ for locked condition). 1 Open Drain, Active Low (output ‘low’ for unlocked condition, high-Z for locked condition). Application: “Auxiliary Output” on page 14 Note: AUX_OUT is an unlock indicator, signalling an error condition when the PLL is unlocked. Therefore, the pin polarity is defined relative to the unlock condition. 8.6.2 Reference Clock Input Divider (RefClkDiv[1:0]) Selects the input divider for the timing reference clock. 8.7 RefClkDiv[1:0] Reference Clock Input Divider REF_CLK Frequency Range 00 ÷ 4. 32 MHz to 75 MHz (50 MHz with XTI) 01 ÷ 2. 16 MHz to 37.5 MHz 10 ÷ 1. 8 MHz to 18.75 MHz 11 Reserved. Application: “Internal Timing Reference Clock Divider” on page 11 Function Configuration 2 (Address 17h) 7 Reserved 8.7.1 6 Reserved 5 Reserved 4 ClkOutUnl 3 Reserved 2 Reserved 1 Reserved 0 Reserved Enable PLL Clock Output on Unlock (ClkOutUnl) Defines the state of the PLL output during the PLL unlock condition. 22 ClkOutUnl Clock Output Enable Status 0 Clock outputs are driven ‘low’ when PLL is unlocked. 1 Clock outputs are always enabled (results in unpredictable output when PLL is unlocked). Application: “PLL Clock Output” on page 14 DS759PP1 CS2200-CP 9. CALCULATING THE USER DEFINED RATIO Note: The software for use with the evaluation kit has built in tools to aid in calculating and converting the User Defined Ratio. This section is for those who are not interested in the software or who are developing their systems without the aid of the evaluation kit. Most calculators do not interpret the fixed point binary representation which the CS2200 uses to define the output to input clock ratio (see Section 5.2.1 on page 12); However, with a simple conversion we can use these tools to generate a binary or hex value which can be written to the Ratio register. 9.1 12.20 Format To calculate the User Defined Ratio (RUD) to store in the register(s), divide the desired output clock frequency by the given input clock (RefClk). Then multiply the desired ratio by the scaling factor of 220 to get the scaled decimal representation; then use the decimal to binary/hex conversion function on a calculator and write to the register. A few examples have been provided in Table 2. Scaled Decimal Representation = (output clock/input clock) • 220 Hex Representation of Binary RUD 12.288 MHz/10 MHz=1.2288 1288490 00 13 A9 2A 11.2896 MHz/44.1 kHz=256 268435456 10 00 00 00 Desired Output to Input Clock Ratio (output clock/input clock) Table 2. Example 12.20 R-Values DS759PP1 23 CS2200-CP 10.PACKAGE DIMENSIONS 10L MSOP (3 mm BODY) PACKAGE DRAWING (Note 1) N D E11 c E A2 A ∝ e b A1 SIDE VIEW 1 2 3 END VIEW L SEATING PLANE L1 TOP VIEW DIM MIN INCHES NOM A A1 A2 b c D E E1 e L L1 -0 0.0295 0.0059 0.0031 ----0.0157 -- -----0.1181 BSC 0.1929 BSC 0.1181 BSC 0.0197 BSC 0.0236 0.0374 REF MAX 0.0433 0.0059 0.0374 0.0118 0.0091 ----0.0315 -- MIN MILLIMETERS NOM NOTE MAX -0 0.75 0.15 0.08 ----0.40 -- -----3.00 BSC 4.90 BSC 3.00 BSC 0.50 BSC 0.60 0.95 REF 1.10 0.15 0.95 0.30 0.23 ----0.80 -- 4, 5 2 3 Notes: 1. Reference document: JEDEC MO-187 2. D does not include mold flash or protrusions which is 0.15 mm max. per side. 3. E1 does not include inter-lead flash or protrusions which is 0.15 mm max per side. 4. Dimension b does not include a total allowable dambar protrusion of 0.08 mm max. 5. Exceptions to JEDEC dimension. THERMAL CHARACTERISTICS Parameter Junction to Ambient Thermal Impedance 24 JEDEC 2-Layer JEDEC 4-Layer Symbol Min Typ Max Units θJA θJA - 170 100 - °C/W °C/W DS759PP1 CS2200-CP 11.ORDERING INFORMATION Product Description Package Pb-Free CS2200-CP Clocking Device 10L-MSOP Yes CS2200-CP Clocking Device 10L-MSOP Yes CDK2000 Evaluation Platform - Yes Grade Temp Range Container Commercial - Order# -10° to +70°C Rail CS2200-CP-CZZ -10° to +70°C Tape and Reel CS2200-CP-CZZR - - CDK-2000-CLK 12.REFERENCES 1. Audio Engineering Society AES-12id-2006: “AES Information Document for digital audio measurements Jitter performance specifications,” May 2007. 2. Philips Semiconductor, “The I²C-Bus Specification: Version 2,” Dec. 1998. http://www.semiconductors.philips.com 13.REVISION HISTORY Release Changes A1 Initial Release A2 Updated AC Electrical Characteristics PP1 Updated “AC Electrical Characteristics” on page 7 Contacting Cirrus Logic Support For all product questions and inquiries, contact a Cirrus Logic Sales Representative. To find one nearest you, go to www.cirrus.com IMPORTANT NOTICE “Preliminary” product information describes products that are in production, but for which full characterization data is not yet available. Cirrus Logic, Inc. and its subsidiaries (“Cirrus”) believe that the information contained in this document is accurate and reliable. However, the information is subject to change without notice and is provided “AS IS” without warranty of any kind (express or implied). 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DS759PP1 25 CS2200-CP 26 DS759PP1