XRT73LC00 datasheet(13/53 Pages) EXAR

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XRT73LC00

E3/DS3/STS-1 LINE INTERFACE UNIT

PRELIMINARY

REV. P1.0.1

TTIP

Transmit RING Output:

The XRT73LC00 uses this pin along with TRING to transmit a bipolar line signal

via a 1:1 transformer.

NOTE: This output pin along with TRING is tri-stated anytime the TxOFF input

pin or bit-field is set “high”.

TxAVDD

Transmit Analog Power Supply

MRING

Monitor Ring Input:

This input pin along with the MTIP pin function as the input pins for the Transmit

Drive Monitor. These two input pins are used to determine whether or not a

bipolar line signal is being output via the TTIP and TRING output pins. The

Transmit Drive Monitor circuit will toggle the DMO output pin “high” denoting a

Transmit Line Fault condition if no bipolar pulses are detected via the TTIP/

TRING output pins for 128 bit-periods.

Connect this input pin to the TRING output pin via a 270 ohm resistor.

NOTE: Tie this input pin to GND if you do not intend to use the Transmit Drive

Monitor.

MTIP

Monitor Tip Input:

This input pin along with the MRING pin function as the input pins for the Trans-

mit Drive Monitor. These two input pins are to be used to determine whether or

not a bipolar line signal is being output via the TTIP and TRING output pins. The

Transmit Drive Monitor circuit will toggle the DMO output pin “high” denoting a

Transmit Line Fault condition if no bipolar pulses are detected via the TTIP/

TRING output pins for 128 bit periods.

Connect this input pin to the TTIP output pin via a 270 ohm resistor.

NOTE: Tie this input pin to GND if you do not intend to use the Transmit Drive

Monitor.

PIN DESCRIPTION

PIN #SYMBOL

TYPE

DESCRIPTION

XRT73LC00 Datasheet(PDF) 13 Page - Exar Corporation