CMX673E3 CML Microcircuits

CMX673 Call Progress Tone Detector D/673/5 June 2001 Provisional Issue Features Applications Worldwide Tone Compatibility Worldwide Payphone Systems Single and Dual Tones Detected Telephone Redialling Systems Wide Dynamic Signal Range Dialling Modems Fast Response Time Banking and Billing Systems Low Power Operation 500A at 3.0V Telecom Test Equipment 3.58MHz Xtal/Clock Oscillator Telecom Security Systems 1.1 Brief Description The CMX673 is a general purpose call progress tone detector for use in Public Switched Telephone System (PSTN) applications. Call progress detection allows equipment which dials into the PSTN network to monitor the progress of the resulting call. Ringing, Busy, Not available and Answer states can be determined. The CMX673 uses advanced digital signal processing techniques to detect tones in the frequency band 315Hz to 650Hz. The use of DSP techniques allows the CMX673 to distinguish between valid call progress tone signals and line noise or voice, low false detection rates result. This is in contrast to other call progress detection devices which are based on simple filtering techniques. The detection timing of the CMX673 allows it to operate with almost any call progress system. In particular the stuttered dial tone of voice mail messaging systems is supported. The use of digital processing and small geometry CMOS design techniques allows the CMX673 to offer a complete call progress detector which analyses both frequency and amplitude in a single 8 pin package. This, coupled with industry leading performance and substantially lower power supply requirements than comparable devices, demonstrates CMLs unique capability in this area. A single 3.58MHz crystal ensures accurate and repeatable performance. With supply requirements between 2.7V and 5.5V the CMX673 can be easily integrated into a wide range of telecom equipments. The CMX673 is pin to pin compatible with the M980 and TSC 75T980 and SSI980. It is available in DIP, TSSOP and SOIC packages. The CMX673 integrated circuit coupled with cadence measurement of the signals detected can identify virtually all call progress tones used worldwide. 2001 Consumer Microcircuits Limited CONTENTS Section Page 1.0 Features and Applications ............................................................. 1 1.1 Brief Description ................................................................................. 2 1.2 Block Diagram...................................................................................... 3 1.3 Signal List .............................................................................................. 4 1.4 External Components....................................................................... 5 1.5 General Description........................................................................... 6 1.5.1 Overall Function Description..................................................... 6 1.5.1 Software Description .................................................................. 6 1.5.2 Glossary........................................................................................ 6 1.5.3 Block Diagram Description........................................................ 7 1.5.4 Decode Output Truth Table ....................................................... 7 1.6 Application Notes ............................................................................... 8 1.6.1 General.......................................................................................... 8 1.7 Performance Specification............................................................. 9 1.7.1 Electrical Performance ............................................................... 9 1.7.2 Packaging................................................................................... 12 2001 Consumer Microcircuits Limited 2 D/673/5