DESCRIPTION:
The IDT82V2081 can be configured as asingle channel T1, E1 or J1 Line Interface Unit. In receive path, an Adaptive Equalizer is integrated to remove the distortion introduced bythe cable attenuation. The IDT82V2081 also performs clock/data recovery, AMI/B8ZS/HDB3 line decoding and detects and reports the LOS conditions. In transmit path, there is an AMI/B8ZS/HDB3 encoder, Waveform Shaper and LBOs. There is one Jitter Attenuator, which can be placed in either the receive path or the transmit path. The Jitter Attenuator can also be disabled. The IDT82V2081 supports both Single Rail and Dual Rail system interfaces. To facilitate the network maintenance, a PRBS/QRSS generation/detection circuit is integrated in the chip, and different types of loopbacks can be set according to the applications. Four different kinds of line terminating impedance, 75 Ω, 100 Ω, 110 Ω and 120 Ω are selectable. The chip also provides driver short-circuit protection and internal protection diode.The chip can be controlled by either software or hardware.
The IDT82V2081 can be used in LAN, WAN, Routers, Wireless Base Stations, IADs, IMAs, IMAPs, Gateways, Frame Relay Access Devices, CSU/DSU equipment, etc.

FEATURES:
• Single channel T1/E1/J1 long haul/short haul line interfaces
• Supports HPS (Hitless Protection Switching) for 1+1 protection without external relays
• Receiver sensitivity exceeds -36 dB@772KHz and -43 dB@1024 KHz
• Programmable T1/E1/J1 switchability allowing one bill of material for any line condition
• Single 3.3 V power supply with 5 V tolerance on digital interfaces
• Meets or exceeds specifications in
   - ANSI T1.102, T1.403 and T1.408
   - ITU I.431, G.703,G.736, G.775 and G.823
   - ETSI 300-166, 300-233 and TBR12/13
   - AT&T Pub 62411
• Software programmable or hardware selectable on:
   - Wave-shaping templates for short haul and long haul LBO (Line Build Out)
   - Line terminating impedance (T1:100 Ω, J1:110 Ω, E1:75 Ω/120 Ω)
   - Adjustment of arbitrary pulse shape
   - JA (Jitter Attenuator) position (receive path or transmit path)
   - Single rail/dual rail system interfaces
   - B8ZS/HDB3/AMI line encoding/decoding
   - Active edge of transmit clock (TCLK) and receive clock (RCLK)
   - Active level of transmit data (TDATA) and receive data (RDATA)
   - Receiver or transmitter power down
   - High impedance setting for line drivers
   - PRBS (Pseudo Random Bit Sequence) generation and detection with 215-1 PRBS polynomials for E1
   - QRSS (Quasi Random Sequence Signals) generation and detection with 220-1 QRSS polynomials for T1/J1
   - 16-bit BPV (Bipolar Pulse Violation) /Excess Zero/PRBS or QRSS error counter
   - Analog loopback, Digital loopback, Remote loopback and Inband loopback
• Cable attenuation indication
• Adaptive receive sensitivity
• Short circuit protection and internal protection diode for line drivers
• LOS (Loss Of Signal) & AIS (Alarm Indication Signal) detection
• Supports serial control interface, Motorola and Intel Multiplexed interfaces and hardware control mode
• Package:
   IDT82V2081: 44-pin TQFP