XRT75L03D Datasheet, PDF (77/134 Pages) Exar Corporation – THREE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER

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XRT75L03D
THREE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER REV. 1.0.0
BIT NUMBER
NAME
4
Analog LOS Defect
Declared
TYPE
R/O
DEFAULT
VALUE
DESCRIPTION
0
Analog LOS Defect Declared:
This READ-ONLY bit-field indicates whether or not the
Analog LOS (Loss of Signal) detector is declaring the LOS
Defect condition.
For DS3 and STS-1 applications, the Analog LOS Detector
will declare the LOS Defect condition whenever it deter-
mines that the amplitude of the pulses (within the incoming
DS3/STS-1 line signal) drops below a certain Analog LOS
Defect Declaration threshold level.
Conversely, (again for DS3 and STS-1 applications) the
Analog LOS Detector will clear the LOS Defect condition
whenever it determines that the amplitude of the pulses
(within the incoming DS3/STS-1 line signal) has risen
above a certain Analog LOS Defect Clearance threshold
level.
It should be noted that, in order to prevent "chattering"
within the Analog LOS Detector output, there is some built-
in hysteresis between the Analog LOS Defect Declaration
and the Analog LOS Defect Clearance threshold levels.
0 - Indicates that the Analog LOS Detector is NOT declar-
ing the LOS Defect Condition.
1 - Indicates that the Analog LOS Detector is currently
declaring the LOS Defect condition.
NOTES:
1. LOS Detection (within each channel of the
XRT75L03D) is performed by both an Analog
LOS Detector and a Digital LOS Detector. The
LOS state of a given Channel is simply a WIRED-
OR of the LOS Defect Declare states of these two
detectors.
2. The current LOS Defect Condition (for the
channel) can be determined by reading out the
contents of Bit 1 (Receive LOS Defect Declared)
within this register.
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