XRT73LC03A Datasheet, PDF (45/61 Pages) Exar Corporation – 3 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT

XRT73LC03A
3 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT
REV. 1.0.1
forced to "0". Once the LOS condition has been
cleared, then the channel(n) resumes normal trans-
mission of the recovered data to the Receiving Termi-
nal.
This feature is available whenever XRT73LC03A is
operating in the HOST Mode or Hardware Mode.
a. Operating in the Hardware Mode.
The Muting upon LOS feature is enabled by pulling
the LOSMUTEN output pin “High". This enables the
Muting upon LOS feature globally for all channels.
b. Operating in the HOST Mode.
The Muting upon LOS feature for each Channel can
be enabled by writing a "1" into the LOSMUT_(n) bit-
field within Command Register 3.
COMMAND REGISTER CR3-(n)
D4
D3
D2
D1
D0
(SR/DR)_(n)
LOSMUT_(n)
RxOFF_(n)
RxClk_(n)INV
Reserved
X
1
x
x
x
NOTE: This step only enables the Muting upon LOS feature
within Channel(n).
3.6 ROUTING THE RECOVERED TIMING AND DATA
INFORMATION TO THE RECEIVING TERMINAL
EQUIPMENT
Each channel takes the Recovered Timing and Data
information, converts it into CMOS levels and routes it
to the Receiving Terminal Equipment via the
RPOS_(n), RNEG_(n) and RxClk_(n) output pins.
Each channel can deliver the recovered data and
clock information to the Receiving Terminal in either a
Single-Rail or Dual-Rail format.
3.6.1 Routing Dual-Rail Format Data to the
Receiving Terminal Equipment
Whenever a channel delivers Dual-Rail format to the
Terminal Equipment, it does so via the following sig-
nals.
• RPOS_(n)
• RNEG_(n)
• RxClk_(n)
Figure 28 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 28. THE TYPICAL INTERFACE FOR THE TRANSMISSION OF DATA IN A DUAL-RAIL FORMAT,
FROM THE RECEIVE SECTION OF THE XRT73LC03A TO THE RECEIVING TERMINAL EQUIPMENT
RxPOS RPOS
Terminal
Equipment
(E3/DS3 or STS-1
Framer)
RxNEG RNEG
RxClk RxClk
Receive
Logic
Block
Exar E3/DS3/STS-1 LIU
The manner that a given channel transmits Dual-Rail scribed below and illustrated in Figure 29. Each
data to the Receiving Terminal Equipment is de-
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