MSTM-S3-IT3-19.44M

MSTM-S3-IT3-19.44M Stratum 3 Timing Module 2111 Comprehensive Drive Aurora, Illinois 60505 Phone: 630- 851- 4722 Fax: 630- 851- 5040 www.conwin.com Application The Connor-Winfield MSTM-S3-IT3 Simplified Control Timing Module acts as a complete system clock module for Stratum 3 timing applications in accordance with GR1244, Issue 2 and GR-253, Issue 3. Connor Winfield’s Stratum 3 timing modules helps reduce the cost of your design by minimizing your development time and maximizing your control of the system clock with our simplified design. Features • -40° to 85° Temp. Range • 5V Miniature Timing Module • Redundant 8kHz References • 40 sec., Filtered, Hold Over History • Operational Status Flags Bulletin Page Revision Date Issued By TM034 1 of 16 P01 04 DEC 02 MBatts General Description The Connor-Winfield Stratum 3 Simplified Control Timing Module acts as a complete system clock module for general Stratum 3 timing applications. Full external control input allows for selection and monitoring of any of four possible operating states: 1) Holdover, 2) External Reference #1, 3) External Reference #2, and 4) Free Run. Table #1 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 1 operation (A=1, B=0) results in an output signal that is phase locked to the External Reference Input #1. Mode 2 operation (A=0, B=1) results in an output signal that is phase locked to External Reference Input #2. Holdover mode operation (A=1, B=1) results in an output signal at or near the frequency as determined by the latest (last) lockedsignal input values and the holdover performance of the MSTM. Free Run ModeFree Run mode operation (A=0, B=0) is a guaranteed output of 4.6 ppm of the nominal frequency. 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 10% 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 1-4. Control loop 0.1 Hz filters effectively attenuate any reference jitter, smooth out phase transients, comply with wander transfer and jitter tolerances. Functional Block Diagram Figure 1 CNTL A CNTL B Mode Control Free Run Ref 1 Ref 2 Holdover PLL TVL Free Run Holdover Alarm Out Reference Select Ex Ref 1 Ex Ref 2 Phase Comparator LOL/LOR SYNC_OUT DAC Filters Stratum 3 OCXO DAC Tuning Voltage Monitor FIFO PLL TVL Function Control Table Table 1 CNTL A 0 1 CNTL B 0 0 Operational Mode Free Run (Default Mode) External Reference #1 External Reference #2 Normal Tune Limit LOR + LOL Normal Tune Limit LOR + LOL Ref 1 0 1 1 1 0 0 0 0 Ref 2 0 0 0 0 1 1 1 0 Hold Over 0 0 0 0 0 0 0 1 Free Run 1 0 0 0 0 0 0 0 PLL_TVL 0 0 1 0 0 1 0 0 Alarm Out 1 0 1 1 0 1 1 1 0 1 1 1 Hold Over Absolute Maximum Rating Table 2 Symbol VCC VI Ts Parameter Power Supply Voltage Input Voltage Storage Temperature Minimum -0.5 -0.5 -55 Nominal Maximum 7.0 VCC + 0.5 100 Units Volts Volts deg. C Notes 1.0 1.0 1.0 Data Sheet #: TM034 Page 2 of 16 Rev: P01 Date: 12 / 04 / 02 © Copyright 2002 The Connor-Winfield Corp. All Rights Reserved Specifications subject to change without notice Recommended Operating Conditions Table 3 Symbol Vcc VIH VIL tIN CIN VOH VOL tTRANS Parameter Power supply voltage High level input voltage - TTL Low level input voltage - TTL Input signal transition - TTL Input capacitance High level output voltage, IOH = -4.0mA, VCC = min. Low level output voltage, IOL = 12.0 mA, VCC = min. Clock out transition time 2.4 Minimum 4.75 2.0 0 Nominal 5.00 Maximum 5.25 VCC 0.8 250 15 5.25 0.4 Units Volts Volts Volts ns pF Volts Volts 2.0 Notes 4.0 30 -40 85 ns ns °C tPULSE TOP 8kHz input reference pulse width( positive or negative) Operating temperature Specifications Table 4 Parameter Frequency Range (SYNC_OUT) Supply Current Timing Reference Inputs Jitter, Wander and Phase Transient Tolerances Wander Generation Wander Transfer Jitter Generation Jitter Transfer Phase Transients Free Run Accuracy Hold Over Stability Inital Offset Temperature Drift Maximum Hold Over History Pull-in/ Hold-in Range Lock Time PLL_TVL Alarm Limit Specifications 19.44 MHz 250 mA typical, 400 mA during warm-up (Maximum) Dual 8 kHz references GR-1244-CORE 4.2-4.4, GR-253-CORE 5.4.4.3.6 GR-1244-CORE 5.3, GR-253-CORE 5.4.4.3.2 GR-1244-CORE 5.4 GR-1244-CORE 5.5, GR-253-CORE 5.6.2.3 GR-1244-CORE 5.5, GR-253-CORE 5.6.2.1 GR-1244-CORE 5.6, GR-253-CORE 5.4.4.3.3 4.6 ppm over TOP ±0.37 ppm for initial 24 hrs ±0.05 ppm ±0.28 ppm ±0.04 ppm 40 seconds ±4.6 ppm minimum