XRT73LC03A Datasheet, PDF (27/61 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
redundancy to quickly switch out a defective line card
and switch-in the back-up line card.
FIGURE 13. FUNCTIONAL BLOCK DIAGRAM OF THE XRT73LC03A
E3_(n)
STS-1/DS3_(n)
Host/(HW) RLOL_(n) EXClk_(n) RxOFF
RxClkINV
RTIP_(n)
RRing_(n)
REQEN_(n)
LOSTHR_(n)
SDI
SDO
SClk
CS
REGR
TTIP_(n)
TRing_(n)
MTIP_(n)
MRing_(n)
DMO_(n)
AGC/
Equalizer
Peak
Detector
Slicer
Clock
Recovery
LOS Detector
Serial
Processor
Interface
Loop MUX
Data
Recovery
Invert
HDB3/
B3ZS
Decoder
Device
Monitor
Pulse
Shaping
Tx
Control
HDB3/
B3ZS
Encoder
Transmit
Logic
Duty Cycle Adjust
Channel 0 - (n) = 0
Channel 1 - (n) = 1
Channel 2 - (n) = 2
RxClk_(n)
RPOS_(n)
RNEG_(n)
LCV_(n)
ENDECDIS
RLOS_(n)
LLB_(n)
RLB_(n)
TAOS_(n)
TPData_(n)
TNData_(n)
TxClk_(n)
TxLEV_(n)
TxOFF_(n)
Notes: 1. (n) = 0, 1, or 2 for respective Channels
2. Serial Processor Interface input pins are shared by the three Channels in HOST Mode and redefined in Hardware Mode.
1.0 SELECTING THE DATA RATE
Each channel within the XRT73LC03A can be config-
ured to support the E3 (34.368 Mbps), DS3 (44.736
Mbps) or the SONET STS-1 (51.84 Mbps) rates. Fur-
ther, each channel can be configured to operate in a
mode/data rate that is independent of the other chan-
nels.
Two methods are available to select the data rate for
each channel of the XRT73LC03A.
1.1 CONFIGURING CHANNEL(n)
For the following disscussion the reader should refer
toTable 2 to determine the appropriate Address for
each command register of each channel in the
XRT73LC03A. The command register description re-
fers to CR(x)-(n), where (x) = 0 to 7 and (n) refers to a
particular channel of the XRT73LC03A.
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