Description

The HC5520 is a Monolithic Subscriber Line Interface Circuit (SLIC) for Analog Subscriber Line cards in Central Office and PABX switches.

Features

• Normal and Reversed DC Feed

• Current Limited Loop Feed

• Ringing, Test-In, and Test-Out Relay Drivers

• Thermal Shutdown Protection with Alert Signal

• On-Hook Transmission

• Selectable Transmit and Receive Gain Setting

• Selectable 2-Wire Impedance Matching

• Zero Crossing Ring Trip Detection and Ring Relay

Release

• Parallel Digital Control and Status Monitoring

• Protection Resistors Inside Feedback Loop Allows the

Use of PTC Devices Without Impact on Longitudinal

Balance

• Thermal Management Features

Applications

• CO/PABX Line Circuits