MSTM-S3-T2NC Datasheet, PDF (1/7 Pages) Connor-Winfield Corporation – STRATUM 3 SIMPLIFIED CONTROL TIMING MODULES

THE CONNOR-WINFIELD CORP.
Stratum 3 Simplified Control
Timing Modules (MSTM-S3-T2NC)
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: 1) Holdover, 2) External
Reference #1, 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 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) 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 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 filters effectively attenuate any
reference jitter and smooth out phase transients.
Fig. 1.0
MSTM-S3 PIN ASSIGNMENT
+5Vdc
EX REF 1
GND
EX REF 2
GND
CLK_OUT
GND
SYNC_OUT
GND
HOLDOVER
REF 1
REF2
FREERUN
GND
ALARM OUT
CNTL A
CNTL B
PLL TVL
BOTTOM VIEW
Fig. 2.0
CNTL A
CNTL B
EX REF 1
EX REF 2
0
1
2:4
2
3
2:1
MUX
BLOCK DIAGRAM
FREERUN
REF 1
REF 2
HOLDOVER
PLL TVL
FREE RUN
HOLDOVER
LOCK AND
DETECTION
DAC
FILTERS
DAC
STRATUM3
OCXO
TUNING
VOLTAGE
MONITOR
TCXO
FIFO
No
Connect
PLL TVL
MSTM-S3
ALARM
OUT
SYNC_OUT
CLK_OUT
Table 1.0
CONTROL
INPUT
A
B
0
0
1
0
1
0
1
1
OPERATIONAL MODE
Free Run (Default)
External
Normal
Reference #1 Tune Limit
LOS+LOL
External
Normal
Reference #2 Tune Limit
LOS+LOL
Holdover
REF 1
REF 2
0
0
1
0
1
0
1
0
0
1
0
1
0
1
0
0
HLDOVER
FREERUN
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
0
PLL TVL
0
0
1
0
0
1
0
0
ALARM
OUTPUT
1
0
1
1
0
1
1
1
DATA SHEET #: TM020
DATE: 7/18/00
REVISION #: P00
Page 1 of 7
Specifications are subject to change without notice
FILENAME: TM020.DOC
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