
Exar
Corporation 48720 Kato Road, Fremont CA, 94538
(510) 668-7000
FAX (510) 668-7017
www.exar.com
XRT83SH38
8-CHANNEL T1/E1/J1 SHORT-HAUL LINE INTERFACE UNIT
SEPTEMBER 2006
REV. 1.0.7
GENERAL DESCRIPTION
The XRT83SH38 is a fully integrated 8-channel short-
haul line interface unit (LIU) that operates from a
single 3.3V power supply. Using internal termination,
the LIU provides one bill of materials to operate in T1,
E1, or J1 mode with minimum external components.
The LIU features are programmed through a standard
microprocessor
interface,
controlled through Hardware mode. EXAR’s LIU has
patented high impedance circuits that allow the
transmitter outputs and receiver inputs to be high
impedance when experiencing a power failure or
when the LIU is powered off. Key design features
within the LIU optimize 1:1 or 1+1 redundancy and
non-intrusive monitoring applications to ensure
reliability without using relays.
serial
interface
or
The on-chip clock synthesizer generates T1/E1/J1
clock rates from a selectable external clock frequency
and outputs a clock reference of the line rate chosen.
Additional features include RLOS, a 16-bit LCV
counter for each channel, AIS, QRSS generation/
detection, TAOS, DMO, and diagnostic loopback
modes.
APPLICATIONS
T1 Digital Cross-Connects (DSX-1)
ISDN Primary Rate Interface
CSU/DSU E1/T1/J1 Interface
T1/E1/J1 LAN/WAN Routers
Public switching Systems and PBX Interfaces
T1/E1/J1 Multiplexer and Channel Banks
F
IGURE
1. B
LOCK
D
IAGRAM
OF
THE
XRT83SH38 T1/E1/J1 LIU (H
OST
M
ODE
)
1 of 8 channels, CHANNEL_n
HW/HOST
WR_R/W
RD_DS
ALE-AS
CS
RDY_DTACK/SDO
INT
SER_PAR
ICT
μ
PTS1
μ
PTS2
D[7:0]
μ
PCLK/SCLK
A[7:0]/SDI
RESET
TPOS_n/TDATA_n
TNEG_n/CODES_n
TCLK_n
RCLK_n
RNEG_n/LCV_n
RPOS_n/RDATA_n
RLOS_n
RRING_n
MASTER CLOCK SYNTHESIZER
QRSS
PATTERN
GENERATOR
DMO_n
TTIP_n
TRING_n
TXON_n
HDB3/
B8ZS
ENCODER
TX/RX JITTER
ATTENUATOR
TIMING
CONTROL
TX FILTER
& PULSE
SHAPER
LINE
DRIVER
DRIVE
MONITOR
HDB3/
B8ZS
DECODER
TX/RX JITTER
ATTENUATOR
TIMING &
DATA
RECOVERY
PEAK
DETECTOR
& SLICER
QRSS
DETECTOR
AIS
DETECTOR
LOS
DETECTOR
MICROPROCESSOR/SERIAL INTERFACE CONTROLLER
TEST
MCLKE1
MCLKT1
MCLKOUT
TAOS
RTIP_n
Remote
Loopback
Digital
Loopback
Analog
Loopback