Telephone Signaling Transceiver

The CMX860 is a flexible, low power Telephone Signaling Transceiver IC designed for use in a wide range of line-powered telephone equipment.
The IC combines the functions of a DTMF encoder and decoder, V.23 modulator and demodulator plus call progression circuitry with analog switching between line and phone interfaces. Ring detection, local phone offhook detection, and a relay for line hook-switch operation are also provided under the control of C-BUS. The ring and hook detectors operate while the remainder of the IC is powersaved, generating an interrupt to wakeup the host µC when further processing or signaling is required. All on-chip functions and switching arrangements are controlled via a serial bus (C-BUS). The CMX860 is designed to operate at 2.7V and utilizes MX-COM’s low power DTMF decoder and V.23 modem technology.
The CMX860 is available in 28-pin SSOP (CMX860D6) and 28-pin SOIC (CMX860D1) packages.

FEATUREs
• V.23 1200/75bps FSK Transmit and Receive
• DTMF/Tones Transmit and Receive
• Line & Telephone Complementary Drivers
• Call Progress Decoder
• CAS Tones Detection and Generation
• Simple ‘C-BUS’ Serial Interface
• Low Power Operation
• ‘Powersave’ Standby Mode

APPLICATIONs
• Least Cost Routers
• Vending Machines
• Alarm Systems
• Home Management Systems
• Remote Meter Reading
• Internet Appliance Applications
• Cable TV Set-Top Boxes
• Advanced Feature Phones