XRT73LC00 Datasheet, PDF (6/53 Pages) Exar Corporation – E3/DS3/STS-1 LINE INTERFACE UNIT

XRT73LC00
E3/DS3/STS-1 LINE INTERFACE UNIT
REV. P1.0.1
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PRELIMINARY
PIN DESCRIPTION
PIN DESCRIPTION
PIN #
1
2
3
4
5
6
7
8
9
SYMBOL
TXLEV
TAOS
TxAVDD
DMO
TxAGND
AGND
RxAGND
RTIP
RRING
TYPE
I
I
****
O
****
****
****
I
I
DESCRIPTION
Transmit Line Build-Out Enable/Disable Select:
This input pin is used to enable or disable the Transmit Line Build-Out circuit in
the XRT73LC00.
Setting this pin to “High” disables the Line Build-Out circuit. In this mode, the
XRT73LC00 outputs partially shaped pulses onto the line via the TTIP and
TRING output pins.
Setting this pin to “Low” enables the Line Build-Out circuit. In this mode, the
XRT73LC00 outputs partially-shaped pulses onto the line via the TTIP and
TRING output pins.
To comply with the isolated DSX-3/STSX-1 Pulse Template Requirements per
Bellcore GR-499-Core or Bellcore GR-253-Core:
1. Set this input pin to a "1" if the cable length between the Cross-Connect and
the transmit output of the XRT73LC00 is greater than 225 feet.
2. Set this input pin to a "0" if the cable length between the Cross-Connect and
the transmit output of the XRT73LC00 is less than 225 feet.
This pin is active only if both of the following are true:
(a) The XRT73LC00 is configured to operate in either the DS3 or SONET STS-
1 modes and
(b) The XRT73LC00 is configured to operate in the Hardware Mode.
NOTE: This pin should be tied to GND if the XRT73LC00 is to be operated in the
HOST mode.
Transmit All Ones Select:
A “High” on this pin causes a continuous AMI all “1’s” pattern to be transmitted
onto the line. The frequency of this “1’s” pattern is determined by TCLK.
NOTES:
1. This input pin is ignored if the XRT73LC00 is operating in the HOST
Mode.
2. Tie this pin to GND if the XRT73LC00 is going to be operating in the
HOST Mode.
Transmit Analog Power Supply
Drive Monitor Output:
If no bipolar line signal is detected on the TTIP/TRING output pins via the MTIP
and MRING input pins for 128±32 TCLK periods, then the DMO output pin tog-
gles and remains “High” until the next bipolar pulse is detected.
Transmit Analog Ground
Analog Ground (Substrate)
Receive Analog Ground
Receive TIP Input:
This input pin along with RRING is used to receive the line signal from the
Remote DS3/E3/STS-1 Terminal.
Receive RING Input:
This input pin along with RTIP is used to receive the line signal from the Remote
DS3/E3/STS-1 Terminal.
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