XRT73L03 Datasheet, PDF (45/62 Pages) Exar Corporation – 3 CHANNEL E3/DS3/STS-1 LINE INTERFCE UNIT

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PRELIMINARY
3 CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT XRT73L03
REV. P1.0.13
The MUTing upon LOS feature for each Channel can
be enabled by writing a "1" into the LOSMUT(n) bit-
field in Command Register 3.
COMMAND REGISTER CR3-(N)
D4
D3
D2
D1
D0
SR/(DR)_(n)
LOSMUT(n)
RxOFF(n)
RxClk(n)INV
Reserved
X
1x
x
x
x
NOTE: This step only enables the MUTing upon LOS fea-
ture in Channel(n).
3.6 ROUTING THE RECOVERED TIMING AND DATA
INFORMATION TO THE RECEIVING TERMINAL
EQUIPMENT
3.6.1 Routing Dual-Rail Format Data to the
Receiving Terminal Equipment
Whenever a channel of the XRT73L03 delivers Dual-
Rail format to the Terminal Equipment, it does so via
the following signals:
Each channel in the XRT73L03 takes the Recovered
Timing and Data information, converts it into CMOS
levels and routes it to the Receiving Terminal Equip-
ment via the RPOS(n), RNEG(n) and RxClk(n) output
pins.
Each channel of the XRT73L03 can deliver the recov-
ered data and clock information to the Receiving Ter-
minal in either a Single-Rail or Dual-Rail format.
• RPOS(n)
• RNEG(n)
• RxClk(n)
Figure 24 illustrates the typical interface for the trans-
mission of data in a Dual-Rail Format from the Re-
ceive Section of a channel to the Receiving Terminal
Equipment
.
FIGURE 24. THE TYPICAL INTERFACE FOR THE TRANSMISSION OF DATA IN A DUAL-RAIL FORMAT
FROM THE RECEIVE SECTION OF THE XRT73L03 TO THE RECEIVING TERMINAL EQUIPMENT
RxPOS
Terminal
Equipment
(E3/DS3 or STS-1
Framer)
RxNEG
RxClk
RPOS
RNEG
RxClk
Receive
Logic
Block
Exar E3/DS3/STS-1 LIU
The manner that a given channel transmits Dual-Rail
data to the Receiving Terminal Equipment is de-
scribed below and illustrated in Figure 25. Each
Channel(n) of the XRT73L03 typically updates the
data on the RPOS(n) and RNEG(n) output pins on
the rising edge of RxClk(n).
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