Dtmf Generator Circuit; Dtmf Receiver Circuit - Panasonic KX-TEA308NE Service Manual

KX-TEA308NE

11.9. DTMF GENERATOR CIRCUIT

11.9.1. Composition
A DTMF tone is generated by the DSP in the CPU and sent to an CO line.

11.10. DTMF RECEIVER CIRCUIT

11.10.1. Composition
The DTMF receiver circuit is composes of four DTMF receivers.
IC606 and IC607 are used for the DTMF receivers from SLT connected to the extension.
The DTMF signal is the 4bit parallel data and read by CPU.
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