Telephone Subscriber Pulse Metering & Anti Fraud Tone Processor

The MX651 is a low power integrated circuit which combines 12kHz Subscriber Pulse Metering (SPM) detection with 18kHz tone processing for anti-fraud purposes within a telephone system. Suitable for battery or line powered systems, the MX651 is protected from crosstalk and false decoding by employing high accuracy switched capacitor filters. By using simple logic or µProcessor control the MX651 will:

• Decode 12kHz SPM pulses (in the presence of high level voice and 18kHz signaling) and provide a logic output.
• Transmit an NRZ amplitude 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.

FEATUREs
• Rapid 18kHz tone encoder-decoder can transfer NRZ data
   Tx up to 166bps
   Rx up to 62bps
• 12kHz Subscriber Pulse Metering Detector

APPLICATIONs
• Meets European 12kHz SPM Frequency Specifications
• Payphone Applications
• Card Operated Telephone Installations
• Component Adjustable Input Sensitivity
• Low Power 3.3V/5.0V Operation