Overview

The LC8920 is designed for synchronous, half-duplex, 9,600 bps CMOS single chip modem applications using public telephone networks. This LSI has built-in modulation-demodulation components meeting modem requirements, along with transmitter-receiver filters and V.24 interfacing. In addition, construction of Group 3 and Group 2 facsimile systems has been simplified.

Features

? CCITT recommendations

V.29 (9600 bps, 7200 bps and 4800 bps)

V.27ter (4800 bps and 2400 bps)

V.21ch2 (300 bps)

T.30, T.4 and T.3

? Supports high-speed (V.29 and V.27ter) and lowspeed (V.21ch2) simultaneous reception

? Half-duplex operation

? Capable of supporting Group 3 and Group 2 facsimiles

? Programmable signal tone generation and detection

? Programmable DTMF (Dual Tone Multi Frequency) generation and detection

? Built-in adaptive automatic equalizer

? Built-in amplitude equalizers (rink amplitude equalizer and cable amplitude equalizer)

? Built-in transmitter-receiver filter (digital filter)

? Supports transmit level adjustment (–0.5 dBm step intervals)

? Dynamic receiving range (–7 dBm to –43 dBm)

? Supports adjustment of transmit-receive sensitivity

? DTE (Data Terminal Equipment) interface Serial interface (conforming to CCITT recommended V.24) and parallel interface

? HDLC (High-level Data Link Control) framing function (during applications of CCITT recommended V.21 ch2)

? Programmable call progress tone detection

? Built-in eye-pattern generator

? Built-in diagnostic function

? Low consumption electric power (typ 250mW) and adopted CMOS (Complementary Metal Oxide Semiconductor)

? +5 V single power supply