XRT73R06 Datasheet, PDF (11/68 Pages) Exar Corporation – SIX CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT

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SIX CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT
XRT73R06
REV. 1.0.0
CLOCK INTERFACE
LEAD # SIGNAL NAME TYPE
DESCRIPTION
E15
E3CLK
I E3 Clock Input (34.368 MHz ± 20 ppm):
If any of the channels is configured in E3 mode, a reference clock 34.368 MHz
is applied on this pin.
NOTE: In single frequency mode, this reference clock is not required.
G16
DS3CLK
I DS3 Clock Input (44.736 MHz ± 20 ppm):
If any of the channels is configured in DS3 mode, a reference clock 44.736
MHz. is applied on this pin.
NOTE: In single frequency mode, this reference clock is not required.
C16 STS-1CLK/ I STS-1 Clock Input (51.84 MHz ± 20 ppm):
12M
If any of the channels is configured in STS-1 mode, a reference clock 51.84
MHz is applied on this pin..
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 channels in E3, DS3 or
STS-1 modes.
L15
SFM_EN
I Single Frequency Mode Enable:
Tie this pin “High” to enable the Single Frequency Mode. A reference clock of
12.288 MHz ± 20 ppm is applied.
In the Single Frequency Mode (SFM) a low jitter output clock is provided for
each channel if the CLK_EN bit is set thus eliminating the need for a separate
clock source for the framer.
Tie this pin “Low” if single frequency mode is not selected. In this case, the
appropriate reference clocks must be provided.
NOTE: This pin is internally pulled down
B1
CLKOUT_0 O Clock output for channel 0
T1
CLKOUT_1
B17 CLKOUT_2
T17 CLKOUT_3
D11 CLKOUT_4
P11 CLKOUT_5
Clock output for channel 1
Clock output for channel 2
Clock output for channel 3
Clock output for channel 4
Clock output for channel 5
Low jitter clock output for each channel based on the mode selection (E3,DS3
or STS-1) if the CLKOUTEN_n bit is set in the control register.
This eliminates the need for a separate clock source for the framer.
NOTES:
1. The maximum drive capability for the clockouts is 16 mA.
2. This clock out is available both in SFM and non-SFM modes.
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