XRT75R12_15 Datasheet, PDF (29/90 Pages) Exar Corporation – TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER

REV. 1.0.5
XRT75R12
TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER ATTENUATOR
SYMBOL
RxClk Duty Cycle
RxClk Frequency
E3
DS-3
STS-1
PARAMETER
MIN
TYP
MAX
UNITS
45
50
55
%
34.368
44.736
51.84
MHz
MHz
MHz
t_RRX
t_FRX
t_CO
t_LCVO
RxClk rise time (10% o 90%)
RxClk falling time (10% to 90%)
RxClk to RPOS/RNEG delay time
RxClk to rising edge of LCV output delay
2
4
ns
2
4
ns
4
ns
2.5
ns
3.6 B3ZS/HDB3 Decoder
The decoder block takes the output from the clock and data recovery block and decodes the B3ZS (for DS3 or
STS-1) or HDB3 (for E3) encoded line signal and detects any coding errors or excessive zeros in the data
stream. Whenever the input signal violates the B3ZS or HDB3 coding sequence for bipolar violation or
contains three (for B3ZS) or four (for HDB3) or more consecutive zeros, an active “High” pulse is generated on
the RLCV_n output pins to indicate line code violation.
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