This document describes a simple clap switch circuit that uses an op-amp configured as a comparator to detect voltage differences caused by sound from a microphone. When the circuit detects a clap, the op-amp output briefly goes high, triggering a flip-flop chip to switch the load on or off. The circuit was designed by a reader and successfully tested to operate as a clap switch.

1. Another cool Clap Switch Circuit.
The above circuit of a simple clap switch was provided to me by one of the keen readers of
this blog Mr. Dathan.
The circuit is very to understand:
The opamp here is configured as a comparator, meaning it is positioned to differentiate the
slightest of voltage differences across its two inputs.
When the clap sound hits the mic, a momentary drop of voltage is experienced at pin#2 of the
IC, this situation raises the voltage at pin#3 of the IC for that instant.
As we know, with pin#3 at higher potential than pin#2 makes the output of the IC high, the
condition puts the output of the IC go high momentarily.
This high response triggers the IC 4017 pin#14, and forces its output to either move from
pin#2 to pin#3 or vice versa depending upon the initial situation of the outputs.
The above action switches the load accordingly either to ON or OFF position.
The above clap switch circuit using IC 741 was successfully tried and tested by Mr. Ajay
Dussa. The following prototype images for the same were sent by Mr. Ajay.