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