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XRT75L04D Datasheet, PDF (1/98 Pages) Exar Corporation – FOUR CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
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XRT75L04D
FOUR CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
NOVEMBER 2003
GENERAL DESCRIPTION
The XRT75L04D is a four-channel fully integrated
Line Interface Unit (LIU) with Sonet Desynchronizer
for E3/DS3/STS-1 applications. It incorporates four
independent Receivers, Transmitters and Jitter
Attenuators in a single 176 pin QFP package.
Each channel of the XRT75L04D can be configured
to operate in E3 (34.368 MHz), DS3 (44.736 MHz) or
STS-1 (51.84 MHz) rates that are independent of
each other. Each transmitter can be turned off and tri-
stated for redundancy support and for conserving
power.
The XRT75L04D’s differential receivers provide high
noise interference margin and are able to receive the
data over 1000 feet of cable or with up to 12 dB of
cable attenuation.
The XRT75L04D incorporates an advanced crystal-
less jitter attenuator per channel that can be selected
either in the transmit or receive path. The jitter
attenuator performance meets the ETSI TBR-24 and
Telcordia GR-499, GR-253 specifications. Also, the
jitter attenuator can be used for clock smoothing in
SONET STS-1 to DS3 de-mapping.
The XRT75L04D provides both Serial Microprocessor
Interface as well as Hardware mode for programming
and control.
The XRT75L04D supports local, remote and digital
loop-backs. The XRT75L04D also contains an on-
board Pseudo Random Binary Sequence (PRBS)
generator and detector with the ability to insert and
detect single bit error.
FEATURES
RECEIVER:
• On chip Clock and Data Recovery circuit for high
input jitter tolerance.
• Meets the jitter tolerance requirements as specified
in ITU-T G.823_1993 for E3 and Telcordia GR-499-
CORE for DS3 applications.
• Detects and Clears LOS as per G.775.
• Receiver Monitor mode handles up to 20 dB flat
loss with 6 dB cable attenuation.
• On chip B3ZS/HDB3 encoder and decoder that can
either be enabled or disabled.
• On-chip clock synthesizer generates the
appropriate rate clock from a single frequency
XTAL.
REV. 1.0.1
• Provides low jitter clock outputs for either DS3,E3
or STS-1 rates.
TRANSMITTER:
• Compliant with Telcordia GR-499, GR-253 and
ANSI T1.102 Specification for transmit pulse
• Tri-state Transmit output capability for redundancy
applications
• Transmitters can be turned on or off.
JITTER ATTENUATOR:
• On chip advanced crystal-less Jitter Attenuator.
• Jitter Attenuators can be selected in Receive or
Transmit paths.
• Compliant with jitter transfer template outlined in
ITU G.751, G.752, G.755, GR-253 and GR-499-
CORE,1995 standards.
• Meets ETSI TBR 24 Jitter Transfer Requirements.
• 16 ,32 or 128 bits selectable FIFO size.
• Meets the Wander specifications described in
T1.105.03b.
• Jitter Attenuators can be disabled.
CONTROL AND DIAGNOSTICS:
• Serial Microprocessor Interface for control and
configuration.
• Supports optional internal Transmit Driver
Monitoring.
• PRBS error counter register to accumulate errors.
• Supports Local, Remote and Digital Loop-backs.
• Single 3.3 V ± 5% power supply.
• 5 V Tolerant I/O.
• Maximum Power Dissipation 1.8W.
• Available in 176 pin QFP package
• - 40°C to 85°C Industrial Temperature Range.
APPLICATIONS
• E3/DS3 Access Equipment.
• STS1-SPE to DS3 Mapper.
• DSLAMs.
• Digital Cross Connect Systems.
• CSU/DSU Equipment.
• Routers.
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com