DRIVING SIGNAL SENSING CIRCUIT WITH DRIVING VOLTAGE STABILIZING CIRCUIT OF RECEIVER

摘要

The circuit comprises the steps of; forcing the DTMF receiver to be in starting state; connecting the emitter and collector between the output terminal of the bridge circuit (1) and the input terminal of the limit power supply; connecting the zener diode and transistor with the base terminal of the transistor (8); turnning on the transistor (8); holding the gating voltage at a constant.