Flip-flop sound responder circuit diagram is a circuit that will create flip-flop output as a reaction from sound as an input. A condenser microphone is used for picking up the sound, this sound act as a toggle for the circuit. This circuit uses an opamp IC LM324 and flip-flop IC CD4027. The first two opamps in the IC LM324 is used to amplify sound from the condenser microphone, and the third opamp wired as a level detector. Whenever the voltage produced by the sound is more than voltage reference (pin 5 of the third opamp), its output (pin 7) goes high and triggering the flip-flop IC CD4027. As the result, the state of the flip-flop IC output (pin 1 and pin 2) will toggles for each burst of sound. Use a condenser mic for this circuit and use all capacitors with rate 10V. the sensitivity of the circuit can be adjusted by carrying the present R9.
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