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.

FEATUREs
• Two Integrated Telecoms Functions:
   • 12kHz SPM Detector
   • Half Duplex 18kHz Modem
• Low Power (3.3V) Requirement
• Component Adjustable Input Sensitivity
• Compact 16-pin Small Outline (SOIC) Package
• Meets European 12kHz SPM Frequency Specifications
• Card Operated Telephone Installations
• Worldwide Pay-Phone Applications