CML Semiconductor Products
Call Progress Tone Detector
1.0
Features
Worldwide Application
Single Tone Decoding
Dual Tone Decoding
US-Busy Tones Identified
Special Information Tones Identified
FX643
D/643/4 March 1996
Provisional Issue
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Voice Detected
Wide Dynamic Signal Range
Low Working Voltage
Standard 3.58MHz Clock Input
Standard 8-pin DIP and 16-pin
SOIC Packages
1.1
Brief Description
The FX643 decodes the audible tone signals provided by Telecom Systems Worldwide to indicate
Dial, Ringing, Busy, Unobtainable and other stages of a call attempt. Detection of these signals is
essential to applications involving machine dialling or automatic call placement. The FX643 provides
the key features needed for intelligent full-function Call Progress monitoring.
In addition to detecting the full range of standard Call Progress tones, the FX643 adds single and dual
tone decoding for better cross-system Call Progress monitoring. The FX643 also directly identifies the
"US Busy" tones, and the international Special Information Tones, saving the time needed for
"cadence verification" under Busy and Unobtainable conditions. The FX643 will also decode and
indicate speech, or other Non-Call Progress signals: this reduces voice-falsing of Call Progress tones
and adds Voice-Answer as a "connected" prompt.
The FX643 uses new digital signal processing techniques to provide these advantages. It is a low
cost, low power product with superior performance. It is available in industry standard
8-pin and 16-pin packages.
©
1996 Consumer Microcircuits Limited