Exar
Corporation 48720 Kato Road, Fremont CA, 94538
(510) 668-7000
FAX (510) 668-7017
www.exar.com
PRELIMINARY
XRT79L73
3 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
JUNE 2004
HARDWARE MANUAL
REV. P1.0.0
The XRT79L73 is a three channel, ATM UNI/PPP
Physical Layer Processor with integrated DS3/E3
framing controllers and Line Interface Units with Jitter
Attenuators that are designed to support ATM direct
mapping and cell delineation as well as PPP mapping
and Frame processing. For ATM UNI applications,
this device provides the ATM Physical Layer (Physi-
cal Medium Dependent and Transmission Conver-
gence sub-layers) interface for the public and private
networks at DS3/E3 rates. For Clear-Channel Framer
applications, this device supports the transmission
and reception of “user data” via the DS3/E3 payload.
The
XRT79L73
includes
Interface Unit with Jitter Attenuator that supports
mapping of ATM or HDLC framed data. A flexible
parallel
microprocessor
interface
configuration and control. Industry standard UTOPIA II
and POS-PHY interface are also provided.
DS3/E3
Framing,
Line
is
provided
for
GENERAL FEATURES:
Integrated T3/E3 Line Interface Unit
Integrated Jitter Attenuator that can be selected
either in Receive or Transmit path
Flexible integrated Clock Multiplier that takes single
frequency clock and generates either DS3 or E3
frequency.
8/16 bit UTOPIA Level I and II and PPP Multi-PHY
Interface operating at 25, 33 or 50 MHz.
HDLC
Controller
that
extraction
of
either
encapsulated packet from DS3/E3 Frame.
Contains on-chip 16 cell FIFO (configurable in
depths of 4, 8, 12 or 16 cells), in both the Transmit
(TxFIFO) and Receive Directions (RxFIFO)
Contains on-chip 54 byte Transmit and Receive
OAM Cell Buffer for transmission, reception and
processing of OAM Cells
Supports ATM cell or PPP Packet Mapping
Supports M13 and C-Bit Parity Framing Formats
Supports DS3/E3 Clear-Channel Framing.
Includes PRBS Generator and Receiver
Supports Line, Cell, and PLCP Loop-backs
Interfaces to 8 Bit wide Intel, Motorola or PowerPC
Low power 3.3V, 5V Input Tolerant, CMOS
Available in 456 Lead PBGA Package
JTAG Interface
provides
bit
the
byte
mapping/
mapped
or
L
INE
I
NTERFACE
U
NIT
On chip Clock and Data Recovery circuit for high
input jitter tolerance
Meets E3/DS3 Jitter Tolerance Requirements
Detects and Clears LOS as per G.775.
Receiver Monitor mode handles up to 20 dB flat
loss with 6 dB cable attenuation
Compliant with jitter transfer template outlined in
ITU G.751, G.752, G.755 and GR-499-CORE,1995
standards
Meets ETSI TBR 24 and GR-499 Jitter Transfer
Requirements
On chip B3ZS/HDB3 encoder and decoder that can
be either enabled or disabled
On-chip clock synthesizer provides the appropriate
rate clock from a single 12.288 MHz Clock
On chip advanced crystal-less Jitter Attenuator
Jitter Attenuator can be selected in Receive or
Transmit paths
16 or 32 bits selectable FIFO size
Meets
the
Jitter
and
described in T1.105.03b,ETSI TBR-24, Bellcore
GR-253 and GR-499 standards
Jitter Attenuator can be disabled
Maximum power consumption 3.1W
DS3/E3 F
RAMER
DS3 framer supports both M13 and C-bit parity.
DS3 framer meets ANSI T1.107 and T1.404
standards.
Detects OOF,LOF,AIS,RDI/FERF alarms.
Generation and Insertion of FEBE on received
parity errors supported.
Automatic insertion of RDI/FERF on alarm status.
E3 framer meets G.832,G.751 standards.
Framers can be bypassed.
ATM/PPP PROTOCOL PROCESSOR
T
RANSMIT
C
ELL
P
ROCESSING
Extracts ATM cells
Supports ATM cell payload scrambling
Maps ATM cells into E3 or DS3 frame
PLCP frame and mapping of ATM cell streams
R
ECEIVE
C
ELL
P
ROCESSING
Wander
specifications