CM8870 CMOS Integrated DTMF Receiver

Posted on Feb 5, 2014

The CAMD CM8888 8888-2 is a fully integrated DTMF Transceiver, featuring adjustable guard time, Automatic Tone burst mode, call progress mode, and a fully compatible 8051 8086/8 Microprocessor Interface The CM8888 8888-2 is manufactured using state-of-the-art advanced CMOS technology for low power consumption and precise data handling. The CM8888

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8888-2 is based on the industry standard CM8870 DTMF Receiver, while the transmitter utilizes a switched- capacitor D/A Converter for low distortion, highly accurate DTMF signaling. Internal Counters provide an Automatic Tone burst mode which allows Tone bursts to be transmitted with precise Timing A call progress Filter CAN be selected by an external Microprocessor for analyzing call progress Tones The CM8888-2 is electrically equivalent to the CM8888 but does not include the call progress function. By California Micro Devices Corporation

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