XRT73LC03A Datasheet, PDF (9/61 Pages) Exar Corporation – 3 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT

RECEIVE INTERFACE
PIN #
NAME
96
REGR/
RxClkINV
XRT73LC03A
3 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT
REV. 1.0.1
TYPE
I
DESCRIPTION
Register Reset Input (Invert RxClk(n)) Output - Select:
The function of this pin depends upon whether the XRT73LC03A is oper-
ating in the HOST Mode or in the Hardware Mode.
NOTE: This pin is internally pulled "High".
In the HOST-Mode - Register Reset Input:
Setting this input pin "Low" causes the XRT73LC03A to reset the con-
tents of the Command Registers to their default settings and default
operating configuration.
In the Hardware Mode - Invert RxClk Output Select:
Setting this input pin "High" configures the Receive Section of all Chan-
nels in the XRT73LC03A to invert their RxClk_(n) clock output signals
and configures Channel (n) to output the recovered data via the
RPOS_(n) and RNEG_(n) output pins on the falling edge of RxClk_(n).
Setting this pin "Low" configures Channel (n) to output the recovered
data via the RPOS_(n) and RNEG_(n) output pins on the rising edge of
RxClk_(n).
CLOCK INTERFACE
PIN #
NAME
47
EXClk_0
99
EXClk_1
103
EXClk_2
TYPE
I
DESCRIPTION
External Reference Clock Input - Channel (n):
Apply a 34.368 MHz clock signal for E3 applications, a 44.736 MHz
clock signal for DS3 applications or a 51.84 MHz clock signal for SONET
STS-1 applications.
The Channel (n) Clock Recovery PLL uses this signal as a Reference
Signal for Declaring and Clearing the Receive Loss of Lock Alarm. The
Clock recovery PLL also generates the exact clock for the LIU.
It is permissible to use the same clock that drives the TxClk_(n) input
pin.
It is permissible to operate the three Channels at different data rates.
OPERATING MODE SELECT
PIN #
NAME
TYPE
93
SR/(DR)
I
DESCRIPTION
Receive Output Single-Rail/Dual-Rail Select:
Setting this pin "High" configures the Receive Sections of all Channels to
output data in a Single-Rail Mode to the Terminal Equipment.
Setting this pin "Low" configures the Receive Section of all Channels to
output data in a Dual-Rail Mode to the Terminal Equipment.
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