FX651 Datasheet, PDF (1/16 Pages) CML Microcircuits – SPM and Security Subsystem

CML Semiconductor Products
SPM and Security Subsystem FX651
1.0 Features
• Two Integrated Telecoms
Functions:
• 12kHz SPM Detector
• Half Duplex 18kHz Modem
• Compact 16-pin Small Outline
(SOIC) Package
• Card Operated Telephone
Installations
D/651/4 September 1997
Provisional Information
• Low Power (3.3V) Requirement
• Component Adjustable Input
Sensitivity
• Meets European 12kHz SPM
Frequency Specifications
• Worldwide Pay-Phone
Applications
VBIAS
1.1 Brief Description
The FX651 integrated circuit combines 12kHz Subscriber Private Metering (SPM) detection with 18kHz
tone processing for anti-fraud purposes within a telephone system. This compact, low power device is
suitable for battery or line powered systems. Under simple logic or µProcessor control it will:
Decode 12kHz SPM pulses in the presence of high level voice and 18kHz signalling, and
provide a logic output.
Transmit an NRZ modulated 18kHz security tone to line.
Decode an incoming modulated 18kHz security tone in the presence of high level voice
and 12 kHz SPM tones, and provide a logic output.
Employing high accuracy switched capacitor filters, the FX651 is protected from crosstalk and false
decoding.
© 1997 Consumer Microcircuits Limited