Stratum 3 Simplified Control Timing Modules (MSTM-S3-T2NC)

Transcription

1 DESCRIPTION The Connor-Winfield Stratum 3 Miniature Simplified Control Timing Module acts as a complete system clock module for general Stratum 3 timing applications. The MSTM is designed for external control functions. Full external control input allows for selections and monitoring of any of four possible operating states: ) Holdover, 2) External Reference #, 3) External Reference #2, and 4) Free Run. The table below illustrates the control signal inputs and corresponding operational states: In the absence of External Control Inputs (A,B), the MSTM enters the Free Run mode and signals an External Alarm. The MSTM will enter other operating modes upon application of a proper control signal. Mode operation (A=, B=) results in an output signal that is phase locked to the External Reference Input #. Mode 2 operation (A=, B=) results in an output signal that is phase locked to External Reference Input #2. Holdover mode operation (A=, B=) results in an output signal at or near the frequency as determined by the latest (last) locked-signal input values and the holdover performance of the MSTM. Alarm signals are generated at the Alarm Output during Holdover and Free Run operation. Alarm Signals are also generated by loss-of-lock, loss of Reference, and by a Tune-Limit indication from the PLL. A Tune-Limit alarm signal indicates that the OCXO tuning voltage is approaching within % the limits of its lock capability and that the External Reference Input may be erroneous. A high level indicates an alarm condition. Real-time indication of the operational mode is available at unique operating mode outputs on pins -4. Control loop filters effectively attenuate any reference jitter and smooth out phase transients. Fig.. +5Vdc EX REF EX REF 2 CLK_OUT SYNC_OUT Fig. 2. CNTL A CNTL B 2:4 EX REF EX REF 2 2: MUX MSTM-S3 PIN ASSIGNMENT 2 3 FREERUN REF REF 2 DAC FILTERS TUNING VOLTAGE MONITOR BOTTOM VIEW BLOCK DIAGRAM FREE RUN LOCK AND DETECTION DAC FIFO STRATUM3 OCXO TCXO No Connect REF REF2 FREERUN ALARM OUT CNTL A CNTL B ALARM OUT SYNC_OUT CLK_OUT MSTM-S3 Table. CONTROL INPUT A B OPERATIONAL MODE REF REF 2 HLDOVER FREERUN ALARM OUTPUT Free Run (Default) External Normal Reference # Tune Limit LOS+LOL External Normal Reference #2 Tune Limit LOS+LOL Holdover DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page of 7 Copyright 999,2 Connor-Winfield all rights reserved

2 Fig. 3. T RAN Profile 2 8 TIE (ns) Time (s) Fig 4..E-6 Sample Wander G eneration (T D EV) for ST M /M ST M -S3 T ypical r es po ns e - 3 s eco nd tes t - J itter applied (2 U H z ) ref date A P R kdh.e-9.e-9 TDEV (sec).e-9 TDEV GR244-Fig5. GR244-Fig5-3.E-2.E-3.E-3.E+.E+.E+.E+3 In te g ration Tim e (se c) DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page 2 of 7 Copyright 999,2 Connor-Winfield all rights reserved

3 Fig. 5. Sample MTIE Data for STM-S3/MSTM-S3.E-6 T ypical res pons e - 3 s econd tes t - Jitter applied (2 H z) ref date AP R kdh.e-9 MTIE (s).e-9 MTIE Mask (A) Mask (B) Mask GR E-9.E-3.E+.E+.E+.E+3.E+3 Observation Time (s) Fig. 6. CURRENT DRAW MSTM-S3-T2NC CURRENT (A) TIME (Sec) DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page 3 of 7 Copyright 999,2 Connor-Winfield all rights reserved

4 TABLE 2. ABSOLUTE MAXIMUM RATING SYMBOL PARAMETER MINIMUM NOMINAL MAXIMUM UNITS NOTES V CC Power supply voltage (Vcc to ) Volts. V IN Input voltage with respect to ground -.5 V cc +.5 Volts. T STG Storage temperature Deg. C. Note.: Operation of this device at these or any other conditions beyond those listed under Recommended Operating Conditions is not implied. Exposure to Absolute Maximum Ratings conditions for extended periods of time may affect device reliability. TABLE 3. INPUT AND OUTPUT CHARACTERISTICS SYMBOL PARAMETER MINIMUM NOMINAL MAXIMUM UNITS NOTES V IH High level input voltage (TLL Compatible) 2. V CC V V IL Low level input voltage (TLL Compatible).8 V T IN Input signal transition time 25 ns C IN Input capacitance 5 pf V OH High level output IOH=-8. ma, VCC minimum 2.4 V V OL Low level output IOH=8. ma, VCC maximum.4 V T HL Clock out transition time high-to-low, no load 4. ns T LH Clock out transition time low-to-high, no load 4. ns T RIP Input 8 KHz reference signal positive pulse width 3 ns T RIN Input 8 KHz reference signal negative pulse width 3 ns T OP Standard Operating Temperature 7 Deg. C TABLE 4. SPECIFICATIONS PARAMETER NOTES Frequency Range (SYNC_OUT) 9.44 MHz 5. Frequency Range (CLK_OUT) N/C Supply Current See Fig. 6. Timing Reference Inputs 8 KHz 6. Jitter and Phase Tolerance Ref-GR-244-CORE Wander Generation Ref-GR-244-CORE 5.3 Free-Run Accuracy ±4.6 ppm Holdover Stability ±.37 ppm 2. Initial Offset.5 ppm Temperature.28 ppm Drift.4 ppm Holdover History 3 seconds Pull-in/ Hold-in Range ±4.6 ppm Minimum 3. Lock Time < secs Correction Period 25 µs TVL Alarm =WARNING: Reference nearing operational limit 7. DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page 4 of 7 Copyright 999,2 Connor-Winfield all rights reserved

5 Fig VOLT DC POWER SUPPLY BLOCK DIAGRAM NETWORK TIMING REFERENCE INPUT eg. BITS CLOCK, etc. FREE RUN CLOCK COPY SYSTEM CLOCK +5Vdc EX REF EX REF 2 CLK_OUT SYNC_OUT REF REF 2 FREERUN ALARM OUT CNTL A CNTL B SYSTEM CONTROL AND DATA INPUTS LOSS OF REFERENCE MONITOR SECTION Fig 8. MSTM-S3 PACKAGE WITH COVER MECHANICAL CHARACTERISTICS MECHANICAL SHOCK 883D 22 CONDITION B 5 G s.5 ms. VIBRATION 883D-27 CONDITION A.6 DA or 2 g Peak Acceleration 2 to 2 Hz ENVIRONMENTAL CHARACTERISTICS TEMPERATURE CYCLE 883D METHOD.7 CONDITION B Cycles 55 to +25 Degrees C. HTOB - HIGH TEMPERATURE OPERATING BIAS Hours +25 Degrees C. DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page 5 of 7 Copyright 999,2 Connor-Winfield all rights reserved

6 PIN DESCRIPTIONS Table 5. MSTM- S3 PIN NAME PIN DESCRIPTION PIN # Output. High when the control inputs select Holdover. 2 REF Output. High when the control inputs select EX REF. 3 REF 2 Output. High when the control inputs select EX REF 2. 4 FREERUN Output. High when the control input selects Free Run. 5 Gnd Ground 6 ALARM OUT Output. =, if (FREERUN + + LOS + LOL + ). 7 CNTL A Mode control input. 8 CNTL B Mode control input. 9 Tuning Voltage Alarm. = if CAPTURE RANGE NEAR % OF EXTREME. Gnd Ground SYNC_OUT Synchronized output. 2 Gnd Ground 3 CLK_OUT N/C 4 Gnd Ground 5 EX REF 2 External Reference #2 Input. (8KHz) 6 Gnd Ground 7 EX REF Input. External Reference # Input. (8KHz) 8 +5 Vdc +5 Volt DC Supply NOTES FOR TABLES -5 NOTES: 2. Holdover stability is the cumulative fractional frequency offset containing Initial Offset, Temperature, and Drift components as described by Bellcore GR-244-CORE Pull-in range is the minimum frequency deviation on the reference inputs to the timing module that can be overcome to pull itself into synchronization with the reference. 4. After seconds at stable room temperature. 5. Consult factory for other frequencies. 6. REF-GR244-CORE 3.2. R At level indicates unit is within the extreme % of its operating range tracking the reference. DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page 6 of 7 Copyright 999,2 Connor-Winfield all rights reserved

7 DATA SHEET REVISION HISTORY REVISION REVISION DATE NOTE P 7/8/ Preliminary Realease DATA SHEET #: TM2 REVISION #: P FILENAME: TM2.DOC DATE: 7/8/ Page 7 of 7 Copyright 999,2 Connor-Winfield all rights reserved