SYNCHRONOUS EQUIPMENT STRATUM 3 CLOCK UNIT WITH HF OUTPUTS – SY15-S3 SY15-S3 Date: 5/15/2001 • INTRODUCTION The SY15-S3 is an accurate time and frequency source, with high frequency, outputs that has been designed as a subsystem level module. The module is designed to work within ATM, SONET, SDH, and wireless systems environments where synchronization is vital. The SY15-S3 is an enhanced version of SY01 and is designed for Stratum 3 applications, but also holds certain features that can make it useful for SONET Minimum Clock (SMC) or other kinds of system clocks. • FEATURES √ A synchronization solution for timing, jitter and wander concerns in a single module. √ Complies with ITU-T Recommendations G.813 and ETSI-ETS 300 462-4 and Bellcore GR-1244-CORE for Stratum 3 applications. √ Supports three modes of operation: Locked to any of References (1-5), Holdover and Free-run. √ Accepts reference inputs from up to five independent sources from 8 kHz to 77.76 MHz. √ Provides three high frequency outputs up to 622.08 MHz. √ Loop filtering utilizing application specific software in the digital signal processor (DSP). √ Continuously monitors and evaluate input reference signals. √ Creates a history buffer for Holdover mode operation. √ Manual or Automatic selection between timing modes. √ Alarm and status signal. √ Host interface and JTAG port. √ Small dimensions of 1.8 x 1.8 x 0.60 inch. • APPLICATION The SY15-S3, a Synchronous Equipment Clock (SEC), fulfills clock regeneration function for STRATUM 3 equipment for: ATM, SDH, PDH, and SONET networks. It was designed for network system manufacturers such as: Access Switches, Core Switches, Cross Connects, Digital Multiplexers-Exchangers, and SDH/SONET equipment. The unit is also suitable for designs where a high frequency outputs are required. Wherever a Timing unit with high performance specifications is required, the SY15-S3 can be embedded within the network system and provide all necessary frequencies and interfaces. th RALTRON ELECTRONICS CORP. ! 10651 N.W.19 St ! Florida 33172 ! U.S.A. Tel: 305 593-6033 ! Fax: 305-594-3973 ! e-mail: [email protected] ! Internet: http://www.raltron.com SYNCHRONOUS EQUIPMENT STRATUM 3 CLOCK UNIT WITH HF OUTPUTS – SY15-S3 J-TAG DSP EX REF1 EX REF2 MUX PD1 FLASH RAM EX REF3 DAC 1 OCXO EX REF4 EX REF5 ÷N CNT1 CNT2 CNT3 CONTROL LOGIC ALARM OUT HIGH FREQUENCY SYNTHESIZER PLL UNLOCK REF 1 to OUT 1 OUT 2 REF 5 DIV CPLD ENOUT1 OUT 3 ENOUT3 ENOUT2 Figure 1. - The functional block diagram of SY15-S3 • DESCRIPTION The SY15-S3 synchronization module is a Digital PLL (DPLL), which utilizes application specific software in the digital signal processor (DSP). The DSP is complemented by fast hardware logic (CPLD) where all multiplexers, counters, dividers, phase detectors, and other control logic circuits are completely implemented. The functional block diagram with configuration is shown in figure 1. The configuration utilizes one DPLL with an OCXO as onboard oscillator, and one high frequency synthesizer. The OCXO is driven by a digital-to-analog converter (DAC1) and provides the accurate and stable signal under all conditions. The output frequencies are generated by the synthesizer that uses a VCXO and high frequency dividers to provide the output frequencies on all three outputs. For other configurations, please contact Raltron. " The module operates in the following four timing modes: Free-run In this mode the unit is unlocked to either of the inputs. The accuracy of the output frequencies in this mode is ±4.6ppm. Free-run mode is typically used when a master clock source is required, not valid history of data for the Holdover mode, or immediately following system power-up before network synchronization is achieved. In the Freerun Mode, the SY15-S3 provides timing and synchronization signals that are based on the accuracy of on-board oscillators only, and are not synchronized to the reference signals. Holdover In this mode the module has lost its reference inputs and is utilizing stored timing data, called history, to control the output frequency. Holdover Mode is typically used while network synchronization is temporarily disrupted. In Holdover Mode, the SY15-S3 provides timing, based on data from the history buffer, while unlocked to an external reference signal. The history data is determined while the device is locked to an external reference signal. The stability of the output signal in holdover mode depends primarily on the stability of on-board oscillator and environment effects where the clock is mounted. The SY15-S3 uses an OCXO as an on-board oscillator but other types of oscillators are available. th RALTRON ELECTRONICS CORP. ! 10651 N.W.19 St ! Florida 33172 ! U.S.A. Tel: 305 593-6033 ! Fax: 305-594-3973 ! e-mail: [email protected] ! Internet: http://www.raltron.com SYNCHRONOUS EQUIPMENT STRATUM 3 CLOCK UNIT WITH HF OUTPUTS – SY15-S3 Locked to EX REF.1 In this mode the output of the module is phase locked to input reference 1. Locked to EX REF.2 In this mode the output of the module is phase locked to input reference 2. Locked to EX REF.3 In this mode the output of the module is phase locked to input reference 3. Locked to EX REF.4 In this mode the output of the module is phase locked to input reference 4. Locked to EX REF.5 In this mode the output of the module is phase locked to input reference 5. The EX REF1 to EX REF5 Modes are typically used when a slave clock source is synchronized to the network. In these modes, the SY15-S3 provides timing signals, which are synchronized, to one of five references inputs (EX REF1 or EX REF5). The input reference signals may have a variety of nominal frequencies, which is typically specified by the end user. When the modes are selected the unit goes through a reference evaluation, and then a frequency acquisition, and finally to phase locking. Local Reference Oscillator Depending on the type of clock, a local reference oscillator is selected. For example: for a Stratum 3 type of clock, the local oscillator can be an AT-cut OCXO or in some cases a good TCXO that meets this standard requirements for frequency drift and jitter noise. For other standards please contact the factory. • Control The external control is available for the user to control the operation of the SY15-S3. The three external inputs CNT1, CNT2 and CNT3 provide this feature. Below, the truth table shows behavior of the SY15-S3 module according to the control inputs states. CNT3 0 0 0 0 1 1 1 1 • CNT2 0 0 1 1 0 0 1 1 CNT1 0 1 0 1 0 1 0 1 MODE OF OPERATION Free-run Locked to EX REF1 Locked to EX REF2 Locked to EX REF3 Locked to EX REF4 Locked to EX REF5 Ignored Holdover Input References The SY15-S3 module accepts five input references EX REF1 to EX REF5. End users can specify the frequencies within a range of 8 kHz to 77.76 MHz. The input reference signals are HCMOS/TTL levels with timing characteristic in according to Bellcore GR-1244-core 3.2.1.R3-1 or equivalent standards. Please note that the end user must specify the input frequencies at the time of order. • Output Signals The SY15-S3 module provides three high frequency output signals OUT1, OUT2 and OUT3. The outputs are generated by the high quality low jitter VCXO and scaled by the output frequency converters. The quality of the output significantly depends on the VCXO oscillator and special care was taken to define its specification. The OUT1 and OUT2 are buffered from VCXO output while the OUT3 is derived by dividing the output frequency of the th RALTRON ELECTRONICS CORP. ! 10651 N.W.19 St ! Florida 33172 ! U.S.A. Tel: 305 593-6033 ! Fax: 305-594-3973 ! e-mail: [email protected] ! Internet: http://www.raltron.com SYNCHRONOUS EQUIPMENT STRATUM 3 CLOCK UNIT WITH HF OUTPUTS – SY15-S3 VCXO. The division ratio can be from 1 to 8. All outputs are complementary PECL and can be enabled and disabled by external pins ENOUT1, ENOUT2 and ENOUT3. • SPECIFICATIONS General Specifications Mechanical Power Supply Input Signals Output Signal Signal Quality Performance Warm Up Current Supply Steady State Current Supply Operating Temperature Storage Temperature Humidity Internal Oscillators Number of Inputs Input reference frequency Signal Level Time Reference characteristics Number of Outputs Output 1 Output 2 Output 3 Signal Level 2”(D)x2”(W)x0.75”(H) 1.8”(D)x1.8”(W)x0.60”(H) 5VDC +3.3VDC TBD TBD -20°C to 70°C -40° to 85°C 5% to 95% non-condensing OCXO or TCXO 5 8kHz to 77.76MHz HCMOS/TTL Compatible Other ranges available on request User selectable Bellcore: GR-1244-core 3.2.1.R3-1 3 155,52 or 622.08MHz 155,52 or 622.08MHz 155,52 or 622.08MHz PECL User define Same as Output 1 Output 1 divided by 1,2,4 or 8 Bellcore: GR-1244-core 4.2 ITU-T: G.813 Bellcore: GR-1244-core 4.4 Bellcore: GR-1244-core 5.3 ITU-T: G.812 Bellcore: GR-1244-core 4.3 ITU-T: G.812 Bellcore: GR-1244-core 5.5 ITU-T: G.812 Bellcore: GR-1244-core 5.4 ITU-T: G.812 On all outputs within the bandwidth 12kHz-20MHz GR-1244-core 5.1 ITU-T: G.812 TCXO: ±3.7x10-7 for 24 hours @ ∆T≤±10°C Bellcore: GR-1244-core 5.2 ITU-T: G.812 TCXO: ±280x10-9 within ∆T≤±10°C ±1x10-6 -20°C to 70°C Bellcore: GR-1244-core 5.2 ITU-T: G.812 or adjustable GR-1244-core 3.7 Jitter Tolerance Phase Transient Tolerance Wander Generation Wander Tolerance Jitter Generation and Transfer Wander Transfer Frequency Output Performance Hermetically Sealed Metal box Module on PCB Regulated for PECL Only with OCXO Jitter <1ps RMS Free run accuracy ±4.6ppm Holdover frequency stability ±3.7x10-7 for 24hours Initial Offset ±50x10-9 Temperature ±280x10-9 Drift ±40x10-9 DPLL bandwidth Lock Time Lock accuracy 0.1Hz <30sec ±1x10-11 th RALTRON ELECTRONICS CORP. ! 10651 N.W.19 St ! Florida 33172 ! U.S.A. Tel: 305 593-6033 ! Fax: 305-594-3973 ! e-mail: [email protected] ! Internet: http://www.raltron.com SYNCHRONOUS EQUIPMENT STRATUM 3 CLOCK UNIT WITH HF OUTPUTS – SY15-S3 34 1 HOLDOVER EX REF 1 VCC 33 2 REF 1 EX REF 2 32 3 REF 2 EX REF 3 31 4 REF 3 EX REF 4 30 5 REF 4 ENOUT2 29 6 REF 5 OUT2 28 7 FREERUN OUT2 27 8 RESET GND 26 9 GND ENOUT3 25 10 OUT3 24 11 OUT3 23 12 REV EX REF5 ALARM OUT PVDD 22 13 CNT 1 ENOUT1 21 14 CNT 2 OUT1 20 15 CNT 3 OUT1 19 16 AUTS GND 18 17 PLL UNLOCK Figure 2 – Bottom view • PIN ASSIGNMENT On the picture below it is shown the pin-out for the SY15-S3. The design is done in such a way that is can support basically any other pin-out without changes in the hardware. For other pin-out requirement please contact the Raltron. Pin # 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 Name HOLDOVER REF 1 REF 2 REF 3 REF 4 REF 5 FREERUN RESET GND EX REF 5 ALARM OUT REV CNT 1 CNT 2 CNT 3 AUTS PLL UNLOCK GND OUT1 OUT 1 ENOUT1 PVDD OUT3 OUT3 ENOUT3 GND OUT2 OUT2 ENOUT2 EX REF 4 EX REF 3 EX REF 2 EX REF 1 VCC Description Holdover Signal -> the output is high when the unit is in holdover mode Reference 1 Signal -> the output is high when the unit is using the reference 1 Reference 2 Signal -> the output is high when the unit is using the reference 2 Reference 3 Signal -> the output is high when the unit is using the reference 3 Reference 4 Signal -> the output is high when the unit is using the reference 4 Reference 5 Signal -> the output is high when the unit is using the reference 5 Free-run Signal -> the output is high when the unit is in the free run mode Reset -> input signal, reset the module Ground External Reference 5 Input -> the input signal from reference 5 Alarm signal -> the output is high when there is an alarm in the module. Revertive Input-> to set revertive mode (low), to disable revertive mode set the pin high. Control Input 1 -> the external input for selecting mode of the unit – see table above. Control Input 2 -> the external input for selecting mode of the unit – see table above. Control Input 3 -> the external input for selecting mode of the unit – see table above. Automatic Switching Input -> to select automating switching between references (low), to disable set high. PLL Unlocked Signal -> the output is high when the unit is not locked to any of the references Ground Output 1 complementary -> Complementary signal from the Output 1 Output 1 -> Signal from the O1 Enable Output 1-> Signal enable output 1 when low PECL VDD -> +3.3V, power supply for PECL and VCSO Output 3 complementary -> Complementary signal from the Output 3 Output 3 -> Signal from the O3 Enable Output 3-> Signal enable output 3 when low Ground Output 2 complementary -> Complementary signal from the Output 2 Output 2 -> Signal from the O2 Enable Output 2-> Signal enable output 2 when low External Reference 4 Input -> the input signal from reference 4 External Reference 3 Input -> the input signal from reference 3 External Reference 2 Input -> the input signal from reference 2 External Reference 1 Input -> the input signal from reference 1 Positive Voltage Supply For other pin-out configurations contact the factory! th RALTRON ELECTRONICS CORP. ! 10651 N.W.19 St ! Florida 33172 ! U.S.A. Tel: 305 593-6033 ! Fax: 305-594-3973 ! e-mail: [email protected] ! Internet: http://www.raltron.com SYNCHRONOUS EQUIPMENT STRATUM 3 CLOCK UNIT WITH HF OUTPUTS – SY15-S3 • MECHANICAL DIMENSIONS Figure 3 – The mechanical dimensions. Figure 3. shows the mechanical dimension of the SY15-S3 module. The module can be supplied in two different types of packaging: - Metal box Module without packaging The dimensions shown on figure are valid for first and second type of packaging, the actual dimensions for the third type are 1.8 x 1.8 x 0.60” keeping the pin-out dimensions the same for all of three. The label on the module shows part number, factory name, week and year of production. The height of the module is 0.50” if a TCXO is used as the reference oscillator! th RALTRON ELECTRONICS CORP. ! 10651 N.W.19 St ! Florida 33172 ! U.S.A. Tel: 305 593-6033 ! Fax: 305-594-3973 ! e-mail: [email protected] ! Internet: http://www.raltron.com