GENERAL DESCRIPTION

The XRT83SL28 is a fully integrated 8-channel E1 short-haul LIU which optimizes system cost and performance by offering key design features. The XRT83SL28 operates from a single 3.3V power supply. The LIU features are programmed through a standard serial microprocessor interface or hardware control. 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.

Additional features include TAOS for transmit and receive, RLOS, LCV, AIS, DMO, and diagnostic loopback modes.

FEATURES

? Fully integrated 8-Channel short haul transceivers for E1 (2.048MHz) applications.

? Internal Impedance matching on both receive and transmit for 75? (E1) or 120? (E1) applications.

? Tri-State on a per channel basis for the transmit selection.

? On-Chip transmit short-circuit protection and limiting protects line drivers from damage on a per channel basis.

? Independent Crystal-Less digital jitter attenuators (JA) with 32-Bit or 64-Bit FIFO for the receive or transmit paths

? Driver failure monitor output (DMO) alerts of possible system or external component problems.

? Transmit outputs and receive inputs may be High impedance for protection or redundancy applications on a per channel basis.

? Support for automatic protection switching.

? 1:1 and 1+1 protection without relays.

? RLOS/AIS according to ITU-T G.775 or ETSI-300-233.

? On-Chip HDB3 encoder/decoder for each channel.

? On-Chip digital clock recovery circuit for high input jitter tolerance.

? Line code error and bipolar violation detection.

? Transmit all ones (TAOS) for the Transmit and Receive Outputs.

? Supports local analog, remote, and digital loopback modes.

? Supports gapped clocks for mapper/multiplexer applications.

? Low Power dissipation

? Single 3.3V supply operation (3V to 5V I/O tolerant).

? 144-Pin TQFP package

? -40°C to +85°C Temperature Range

APPLICATIONS

? ISDN Primary Rate Interface

? CSU/DSU E1 Interface

? E1 LAN/WAN Routers

? Public Switching Systems and PBX Interfaces

? E1 Multiplexer and Channel Banks

? Integrated Multi-Service Access Platforms (IMAPs)

? Integrated Access Devices (IADs)

? Inverse Multiplexing for ATM (IMA) Wireless Base Stations