XRT73LC00A Datasheet, PDF (1/53 Pages) Exar Corporation – E3/DS3/STS-1 LINE INTERFACE UNIT

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PRELIMINARY XRT73LC00A
AUGUST 2004
E3/DS3/STS-1 LINE INTERFACE UNIT
REV. P1.0.0
GENERAL DESCRIPTION
The XRT73LC00A DS3/E3/STS-1 Line Interface Unit
is a low power CMOS version of the XRT73L00A and
consists of a line transmitter and receiver integrated
on a single chip and is designed for DS3, E3 or SO-
NET STS-1 applications.
XRT73LC00A can be configured to support the E3
(34.368 Mbps), DS3 (44.736 Mbps) or the SONET
STS-1 (51.84 Mbps) rates.
In the transmit direction, the XRT73LC00A encodes
input data to either B3ZS (for DS3/STS-1 applica-
tions) or HDB3 (for E3 applications) format and con-
verts the data into the appropriate pulse shapes for
transmission over coaxial cable via a 1:1 transformer.
In the receive direction the XRT73LC00A performs
equalization on incoming signals, performs Clock Re-
covery, decodes data from either B3ZS or HDB3 for-
mat, converts the receive data into TTL/CMOS for-
mat, checks for LOS or LOL conditions and detects
and declares the occurrence of line code violations.
The XRT73LC00A also contains a 4-Wire Micropro-
cessor Serial Interface for accessing the on-chip
Command registers.
FEATURES
• Incorporates an improved Timing Recovery circuit
and is pin and functional compatible to XRT73L00A
• Meets E3/DS3/STS-1 Jitter Tolerance Require-
ments
• Full Loop-Back Capability
• Transmit and Receive Power Down Modes
• Full Redundancy Support
• Contains a 4-Wire Microprocessor Serial Interface
• Uses Minimum External components
• Low Power CMOS Design
• Single +3.3V Power Supply
• 5 V Tolerant pins
• -40°C to +85°C Operating Temperature Range
• Available in a 44 pin TQFP package
APPLICATIONS
• Interfaces to E3, DS3 or SONET STS-1 Networks
• CSU/DSU Equipment
• PCM Test Equipment
• Fiber Optic Terminals
• Multiplexers
FIGURE 1. BLOCK DIAGRAM OF THE XRT73LC00A
E3
S TS -1 /D S 3
Ho s t/(H W )
RLOL EXCLK
ICT
RCLKINV
RTIP
RRING
RE Q DIS
LOSTHR
SDI
SDO/(LCV)
SClk
CS
REGRESET
TTIP
TRING
MTIP
MRING
DMO
AGC/
Equalizer
Peak
Detector
Slicer
C lo c k
R e c o ve ry
LOS Detector
Serial
Processor
Interface
Loop MUX
Da ta
Recovery
Invert
HDB3/
B3ZS
Decoder
Device
M o n ito r
P u ls e
Shaping
Tx
Control
HDB3/
B3ZS
Encoder
Tra n sm it
Logic
Duty Cycle Adjust
RCLK1
LCV/(RCLK2)
RPOS
RNEG
DR/SR
RLOS
LLB
RLB
ENDECDIS
TAOS
TPDATA
TNDATA
TClk
TXLEV
TXOFF
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • [phone] • FAX [phone] • www.exar.com