XRT73L02M Datasheet, PDF (7/46 Pages) Exar Corporation – TWO CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT

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TWO CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT
XRT73L02M
REV. 1.0.0
TRANSMIT INTERFACE
PIN #
30
SIGNAL NAME
TxClkINV/
SClk
82
TxMON
74
TxLEV_0
52
TxLEV_1
TYPE
I
I
I
DESCRIPTION
Hardware Mode: Transmit Clock Invert
Host Mode: Serial Clock Input:
Function of this pin depends on whether the XRT73L02M is configured to oper-
ate in Hardware mode or Host mode.
In Hardware mode, setting this input pin “High” configures all the Transmitters to
sample the TPOS_n and TNEG_n data on the rising edge of the TxClk_n .
NOTES:
1. If the XRT73L02M is configured in HOST mode, this pin functions as
SClk input pin (please refer to the pin description for Microprocessor
interface).
Transmitter Monitor:
When this pin is pulled “High”, MTIP and MRING are connected internally to
TTIP and TRING and allows self monitoring of the transmitter.
Transmit Line Build-Out Enable/Disable Select - Channel 0:
Transmit Line Build-Out Enable/Disable Select - Channel 1:
These input pins select the Transmit Line Build-Out circuit.
Setting these pins to "High" disables the Line Build-Out circuit of Channel n. In
this mode, Channel n outputs partially-shaped pulses onto the line via the
TTIP_n and TRing_n output pins.
Setting these pins to "Low" enables the Line Build-Out circuit of Channel n. In
this mode, Channel n outputs shaped pulses onto the line via the TTIP_n and
TRing_n 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 these pins to "1" if the cable length between the Cross-Connect and the
transmit output of Channel is greater than 225 feet.
2. Set these pins to "0" if the cable length between the Cross-Connect and the
transmit output of Channel is less than 225 feet.
These pins are active only if the following two conditions are true:
a. The XRT73L02M is configured to operate in either the DS3 or SONET STS-1
Modes.
b. The XRT73L02M is configured to operate in the Hardware Mode.
NOTES:
1. These pins are internally pulled down.
2. If the XRT73L02M is configured in HOST mode, these pins should be
tied to GND.
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