XRT75L03D Datasheet, PDF (23/134 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
CLOCK INTERFACE
PIN #
SIGNAL NAME
107 E3Clk/ CLK_EN
108 DS3Clk/ CLK_OUT
109 STS-1Clk/ 12M
TYPE
I
I/O
I
DESCRIPTION
E3 Clock Input (34.368 MHz ± 20 ppm):
If all the 3 channels or any one of the channels is configured in E3 mode, a ref-
erence clock 34.368 MHz ± 20 ppm is input to this pin..
Clock Output Enable:
If the Single Frequency Mode is selected, tie this pin “High” to enable the clock
output through the CLK_OUT pin (pin 108).
DS3 Clock Input (44.736 MHz ± 20 ppm):
If all the 3 channels or any one of the channels is configured in DS3 mode, a ref-
erence clock 44.736 MHz ± 20 ppm is input to this pin.
Clock Output:
When the Single Frequency Mode is enabled, this pin is configured as the clock
output from Channel 1.This clock frequency is determined by the Channel 1 set-
ting..
NOTE: This low jitter output clock can be used as the input clock source for the
framer device. thus eliminating the need for a separate clock source for
the framer.
STS-1 Clock Input (51.84 MHz ± 20 ppm):
If all the 3 channels or any one of the channels is configured in STS-1 mode, a
reference clock 51.84 MHz ± 20 ppm is input to this pin.
Single Frequency Mode Clock Input:
In Single Frequency Mode, a reference clock of 12.288 MHz ± 20 ppm is con-
nected to this pin and the internal clock synthesizer generates the appropriate
clock frequencies based on the configuration of the rates (E3 or DS3 or STS-1).
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