XRT73LC04A_08 Datasheet, PDF (36/64 Pages) Exar Corporation – 4 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT

XRT73LC04A
4 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT
REV. 1.0.2
.
FIGURE 20. THE BELLCORE GR-253-CORE TRANSMIT OUTPUT PULSE TEMPLATE FOR SONET STS-1 APPLI-
CATIONS
ST S-1 Pulse T emplate
1.2
1
0.8
0.6
Lower Curve
Upper Curve
0.4
0.2
0
-0.2
-1 _{-0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1}
0 _{0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9}
Time, in UI
1 _{1.1 1.2 1.3 1.4}
2.4.1 Enabling the Transmit Line Build-Out Cir-
cuit
If the Transmit Line Build-Out Circuit is enabled, then
the Transmit Section of the Channel outputs shaped
pulses onto the line via the TTIP_(n) and TRing_(n)
output pins.
Enable the Transmit Line Build-Out circuit for each
channel by doing the following:
a. Operating in the Hardware Mode
Set the TxLEV_(n) input pin to “Low".
b. Operating in the HOST Mode
Set the TxLEV_(n) bit-field to "0", as illustrated below.
COMMAND REGISTER, CR1-(n)
D4
D3
D2
D1
D0
TxOFF_(n)
TAOS_(n)
TxClkINV_(n)
TxLEV_(n)
Reserved
0
X
X
0
X
2.4.2 Disabling the Transmit Line Build-Out Cir-
cuit
If the Transmit Line Build-Out circuit is disabled, then
the XRT73LC04A outputs partially shaped pulses on-
to the line via the TTIP_(n) and TRing_(n) output
pins.
Disable the Transmit Line Build-Out circuit by doing
the following:
a. Operating in the Hardware Mode
Set the TxLEV_(n) input pin to “High".
b. Operating in the HOST Mode
Set the TxLEV_(n) bit-field to "1" as illustrated below.
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