XRT73L03 Datasheet, PDF (11/62 Pages) Exar Corporation – 3 CHANNEL E3/DS3/STS-1 LINE INTERFCE UNIT

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PRELIMINARY
PIN DESCRIPTION
PIN #
47
SIGNAL NAME
EXClk1
48
RxDVDD1
49
RxClk1
50
RNEG1
51
RPOS1
52
NC
53
NC
54
RxDGND1
55
RLOS1
56
LCV1
57
RLOL1
58
RLOS3
59
LCV3
60
RLOL3
3 CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT XRT73L03
REV. P1.0.13
TYPE
I
****
O
O
O
****
O
O
O
O
O
O
DESCRIPTION
External Reference Clock Input - Channel 1:
Apply a 34.368 MHz clock signal for E3 applications, a 44.736 MHz clock sig-
nal for DS3 applications or a 51.84 MHz clock signal for SONET STS-1 appli-
cations.
The Clock Recovery PLL in Channel 1 uses this signal as a Reference Signal
for Declaring and Clearing the Receive Loss of Lock Alarm.
NOTES:
1. It is permissible to use the same clock which is also driving the TxClk
input pin.
2. It is permissible to operate the three Channels at different data rates.
Receive Digital 3.3V+ 5% VDD (for Receiver 1):
Receive Clock Output - Channel 1:
Refer to the description of pin 43, RxClk3
Receive Negative Data Output - Channel 1:
Refer to the description of pin 44, RNEG3
Receive Positive Data Output - Channel 1:
Refer to the description of pin 45, RPOS3
No Connection
No Connection
Receive Digital GND - Channel 1:
Receive Loss of Signal Output Indicator - Channel 1:
This output pin toggles "High" if Channel 1 in the XRT73L03 has detected a
Loss of Signal Condition in the incoming line signal.
The criteria the XRT73L03 uses to declare an LOS Condition depends upon
whether it is operating in the E3 or STS-1/DS3 Mode.
Line Code Violation Indicator - Channel 1:
Whenever the Receive Section of Channel 1 detects a Line Code Violation, it
pulses this output pin "High". This output pin remains "Low" at all other times.
NOTE: The XRT73L03 outputs an NRZ pulse via this output pin. It is advisable
to sample this output pin via the RxClk1 clock output signal.
Receive Loss of Lock Output Indicator - Channel 1:
This output pin toggles "High" if Channel 1 of the XRT73L03 has detected a
Loss of Lock Condition. Channel 1 declares an LOL (Loss of Lock) Condition if
the recovered clock frequency deviates from the Reference Clock frequency
(available at the EXClk(n) input pin) by more than 0.5%.
Receive Loss of Signal Output Indicator - Channel 3:
Refer to the description of pin 55, RLOS1
Line Code Violation Indicator - Channel 3:
Refer to the description of pin 56, LCV1
Receive Loss of Lock Output Indicator - Channel 3:
Refer to the description of pin 57, RLOL1
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