The HC-5509B telephone Subscriber Line Interface Circuit integrates most of the BORSCHT functions on a monolithic IC. The device is manufactured in a Dielectric Isolation (DI) process and is designed for use as a high voltage interface between the traditional telephone subscriber pair (Tip and Ring) and the low voltage filtering and coding/decoding functions of the line card. Together with a secondary protection diode bridge and “feed” resistors, the device will withstand 1000V lightning induced surges, in plastic packages.

Features

? DI Monolithic High Voltage Process

? Compatible with Worldwide PBX and CO Performance Requirements

? Controlled Supply of Battery Feed Current with Programmable Current Limit

? Operates with 5V Positive Supply (VB+)

? Internal Ring Relay Driver and a Utility Relay Driver

? High Impedance Mode for Subscriber Loop

? High Temperature Alarm Output

? Low Power Consumption During Standby Functions

? Switch Hook, Ground Key, and Ring Trip Detection

? Selective Power Denial to Subscriber

? Voice Path Active During Power Denial

? On-Chip Op Amp for 2-Wire Impedance Matching

Applications

? Solid State Line Interface Circuit for PBX or Central Office Systems, Digital Loop Carrier Systems

? Hotel/Motel Switching Systems

? Direct Inward Dialing (DID) Trunks

? Voice Messaging PBXs

? High Voltage 2-Wire/4-Wire, 4-Wire/2-Wire Hybrid

? Related Literature

??? - AN9607, Impedance Matching Design Equations

??? - AN9628, AC Voltage Gain

??? - AN9608, Implementing Pulse Metering

??? - AN549, The HC-5502S/4X Telephone Subscriber Line Interface Circuits (SLIC)