MC145442

Single-chip low-speed CMOS modem integrates an FSK modulator, demodulator, receive filters, carrier detect circuit, and telephone-line duplexer. It supports CCITT V.21 300-baud communication with simplex, half-duplex, and full-duplex operating modes. The device operates from a single 5 V supply over a 4.5 V to 5.5 V recommended range and uses a 3.579 MHz crystal oscillator reference. Operating temperature range is -40 °C to 85 °C, with power-down operation reducing supply current to 300 µA maximum.