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The CM8870 is a DIP (dual in-line package) integrated circuit used for telephone dialing. It is a tone/pulse dialer with a built-in DTMF (dual-tone multi-frequency) receiver. It is designed to be used in telephone systems, modems, and other communication systems. Features: Tone/Pulse Dialing Built-in DTMF Receiver Low Power Consumption Low Cost High Reliability Easy to Use Applications: Telephone Systems Modems Other Communication Systems (For reference only)