ST952 - ST Microelectronics

ST952 D.A.A. LINE INTERFACE

ST952 is a line interface designed to implement Modem application up to 56Kbps and Voice applications. ST952 interfaces between telephone line and capacitive isolation barrier. A complete D.A.A. is made with ST75951 which interfaces between capacitive isolation barrier and the DSP or HSP signals. Tip Digital ST75951 Signals ST952 952-02.EPS If CLID external.

Features

transistor switch is enabled, a limited amount of current, less than 1mA, is drawn from the line. In off-hook state, ST952 DC voltage, 4V at a 20mA line current, allows to interface with most of public networks in the world. The return loss is externally adjustable to real or complex impedance. In case of a wrong connection in a digital phone line, ST952 detects the over current value and sends to ST75951 an alert signal through the capacitive isolation barrier. Before starting a line connection, ST952 is abled to check if the line is used by an other terminal connected on the same telephone .