CMX860 CML Microcircuits Telephone Signalling COMMUNICATION SEMICONDUCTORS Transceiver D/860/7 April 2008 Features Applications V.23 & Bell 202 FSK Tx and Rx Least Cost Routers DTMF/Tones Transmit and Receive Vending Machines Line and Phone Complementary Drivers Internet Appliances Call Progress Decoder Home Management Systems Dual Tone Detection and Generation Remote Meter Reading Simple C-BUS Serial Interface Alarm Systems Low Power Operation Cable TV Set-Top Boxes Powersave Standby Mode Advanced Feature Phones 1.1 Brief Description The CMX860 is a flexible, low-power Telephone Signalling 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 / Bell 202 modulator and demodulator plus call progression circuitry with analogue switching between line and phone interfaces. Ring detection, local phone off-hook detection and a relay driver for line hook-switch operation are also provided under the control of C-BUS . The ring and hook detectors operate whilst the remainder of the IC is powersaved, generating an interrupt to wake-up the host C when further processing or signalling 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 utilises CMLs low power DTMF decoder and V.23 / Bell 202 modem technology. It is available in 28-pin SOIC (D1), TSSOP (E1) and SSOP (D6) packages. 2008 CML Microsystems Plc Telephone Signalling Transceiver / Least Cost Router CMX860 CONTENTS Section Page 1.0 Features and Applications..................................................................... 3 1.1 Brief Description ..................................................................................... 3 1.2 Block Diagram......................................................................................... 5 1.3 Signal List ................................................................................................ 6 1.4 External Components............................................................................. 8 1.4.1 Ring Detector Interface ........................................................... 10 1.4.2 Hook Detector Interface .......................................................... 11 1.4.5 RESETN pin .............................................................................. 11 1.5 General Description.............................................................................. 12 1.5.1 Tx USART.................................................................................. 13 1.5.2 FSK Modulator ......................................................................... 14 1.5.3 Tx Filter and Equaliser ............................................................ 14 1.5.4 DTMF/Tones Generator ........................................................... 14 1.5.5 Tx Level Control and Output Drivers ..................................... 14 1.5.6 DTMF Decoder and Tone Detectors....................................... 15 1.5.7 Rx Modem Filter and Equaliser .............................................. 16 1.5.8 FSK Demodulator..................................................................... 16 1.5.9 Rx Data Register and USART ................................................. 16 1.5.10 Rx Modem Pattern Detectors.................................................. 18 1.5.11 Analogue Signal Routing ........................................................ 18 1.5.12 C-BUS Interface...................................................................... 19 1.5.12.1 General Reset Command ............................... 19 1.5.12.2 General Control Register ............................... 21 1.5.12.3 Transmit Mode Register................................. 23 1.5.12.4 Receive Mode Register................................... 26 1.5.12.5 Tx Data Register.............................................. 28 1.5.12.6 Rx Data Register ............................................. 28 1.5.12.7 Analogue Signal Path Register ..................... 29 1.5.12.8 Status Register................................................ 30 1.5.12.9 Programming Register ................................... 33 1.5.12.10 Other Registers............................................... 35 1.6 Application Notes ................................................................................. 36 1.7 Performance Specification................................................................... 37 1.7.1 Electrical Performance............................................................ 37 1.7.1.1 Absolute Maximum Ratings....................................... 37 1.7.1.2 Operating Limits ......................................................... 37 1.7.1.3 Operating Characteristics.......................................... 38 It is always recommended that you check for the latest product datasheet version from the Datasheets page of the CML website: www.cmlmicro.com . 2008 CML Microsystems Plc 4 D/860/7