MT9045 Zarlink Semiconductor, MT9045 Datasheet - Page 20

• Manufacturer Part Number: MT9045
• Description: T1/E1/OC3 System Synchronizer
• Manufacturer: Zarlink Semiconductor

MT9045
Data Sheet
MT9045
R=3.3M
74HC14
74HC14
Lock
LOCK
IN4148
+
C=1µf
Figure 11 - Time-constant Circuit
A digital alternative to the RC-time-constant circuit is presented in Figure 12. The circuit in Figure 12 can be used to
generate a steady lock signal. The circuit monitors the MT9045’s LOCK pin, as long as it detects a positive pulse
every 1.024 seconds or less, the Advanced Lock output will remain high. If no positive pulse is detected on the
LOCK output within 1.024 seconds, the Advanced LOCK output will go low.
Figure 12 - Digital Lock Pin Circuit
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Zarlink Semiconductor Inc.