XRT59L921 Datasheet, PDF (9/32 Pages) Exar Corporation – TWENTY-ONE CHANNEL E1 LINE INTERFACE UNIT

REV. 1.2.1
PIN DESCRIPTIONS
PIN#
A2
A4
A6
C7
E6
A8
U6
W5
Y6
Y4
W2
Y19
Y17
Y15
V15
U15
E15
C18
B17
A18
B20
B3
B4
B6
D6
E4
B7
U4
V6
W7
W4
W3
W19
W17
W16
V14
U17
E17
C16
B16
B18
B19
SYMBOL
TxClk_0
TxClk_1
TxClk_2
TxClk_3
TxClk_4
TxClk_5
TxClk_6
TxClk_7
TxClk_8
TxClk-9
TxClk_10
TxClk_11
TxClk_12
TxClk_13
TxClk_14
TxClk_15
TxClk_16
TxClk_17
TxClk_18
TxClk_19
TxClk_20
TxNEG_0
TxNEG_1
TxNEG_2
TxNEG_3
TxNEG_4
TxNEG_5
TxNEG_6
TxNEG_7
TxNEG_8
TxNEG_9
TxNEG_10
TxNEG_11
TxNEG_12
TxNEG_13
TxNEG_14
TxNEG_15
TxNEG_16
TxNEG_17
TxNEG_18
TxNEG_19
TxNEG_20
XRT59L921
TWENTY-ONE CHANNEL E1 LINE INTERFACE UNIT
TYPE
I
DESCRIPTION
Transmitter Clock Input – Channel_n:
If the user operates Channel_n (within the XRT59L921) in the Clock mode, then the
Transmit Section of the Channel_n will use the falling edge of this signal to sample
the data at the TxPOS_n and TxNEG_n input pins.
NOTE: If the user operates the Channel_n in the clockless mode, then the Terminal
Equipment should not apply a clock signal to this input pin and TxCLK should
be tied "High".
I Transmitter - Negative Data Input – Channel_n:
The exact signal that should be applied to this input pin depends upon whether the
user intends to operate the Transmit Section (of Channel_n) in the Clock or Clock-
less Mode
Clock Mode:
The Terminal Equipment should apply bit-wide NRZ pulses on this input pin, when-
ever the Terminal Equipment needs to transmit a Negative-Polarity pulse onto the
line via TTIP_n and TRing_n output pins. The XRT59L921 will sample this input pin
upon the falling edge of the TClk_n signal.
Clockless Mode:
The Terminal Equipment should apply RZ pulses to this input pin, anytime the Termi-
nal Equipment needs to transmit a Negative-Polarity pulse onto the line viaTTIP_n
and TRing_n output pins.
NOTE: In clockless mode, transmit output pulse width is determined by the RZ signal
applied to TxNEG/TxPOS.
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