
Exar Corporation
GENERAL DESCRIPTION
The XRT82D20 is a fully integrated, single channel, Line Interface Unit (Transceiver) for 75 Ω or 120 Ω E1 (2.048 Mbps) applications. The LIU consists of a receiver with adaptive data slicer for accurate data and clock recovery and a transmitter which accepts either single or dual-rail digital inputs for signal transmission to the line using a low- impedance differential line driver.
FEATURES
• Complete E1 (CEPT) line interface unit
• Generates transmit output pulses that are
compliant with the ITU-T G.703 Pulse Template for
2.048Mbps (E1) rates
• On-Chip Pulse Shaping for both 75 Ω and 120 Ω
Line Drivers
• Clock Recovery and Selectable Crystal-less Jitter
attenuator
• Compliant with ETS300166 Return Loss
• Compliant with the ITU-T G.823 Jitter Tolerance
Requirements
• Remote, Local and Digital Loop backs
• Declares and Clears LOS per ITU-T G.775
• Logic Inputs accept either 3.3V or 5.0V levels
• - 400C to 850C Temperature Range
• Low Power Dissipation; 145mW with 120 Ω or
160mW with 75 Ω typical
• +3.3V or +5V Supply Operation
• Pin Compatible with the XRT7288
APPLICATIONS
• PDH Multiplexers
• SDH Multiplexers
• Digital Cross-Connect Systems
• DECT (Digital European Cordless Telephone) Base
Stations
• CSU/DSU Equipment
• Test Equipment