Acoustic control switch kit, clap switch, 5V, ICSK050A

The acoustic clap switch module is a compact circuit that turns a hand clap into an electrical command, functioning as a bistable switch: on the first sound detection, the output goes HIGH and provides a 5V signal, and on the next detection it returns to LOW. The board integrates an electret microphone, a two-stage audio amplifier built with transistors Q1 and Q2, a bistable flip-flop circuit constructed with Q3 and Q4, as well as an indicator LED that visually signals the current output state. The R1 and C1 network limits the circuit’s frequency response, providing maximum sensitivity around 3kHz, exactly the range of the sharp sound produced by a clap, which reduces false triggering caused by background noise or speech. This filtering explains the module’s prompt and consistent response to clapping.

Power is supplied at 5VDC, and the low consumption allows operation from a stabilized mains supply, from a USB port, or directly from the 5V pin of a development board. The output available on connector J2 can drive a 5V relay module, which in turn can practically control any type of load: lighting fixtures, fans, pumps, solenoid valves, or other independent circuits. The same output can be read as a digital input by an Arduino Uno, Nano, Mega, or Pro Mini board, allowing the implementation of more complex automation, with delays, activation counting, or additional conditions. For boards that operate at 3.3V, such as ESP32, ESP8266, STM32, or Raspberry Pi Pico, the 5V signal must be adapted using a resistor divider or a logic level converter, otherwise there is a risk of damaging the input pin.

The module is suitable for touchless lighting control, for activating devices in workshops or in spaces where hands are occupied, for home automation projects, for models and demonstration stands, as well as for educational applications in which audio amplification and bistable flip-flop circuits are studied.

Specifications:

Supply voltage: 5VDC

Output type: bistable, toggles on each detection

Output logic level: 5V in active state, LOW in inactive state

Sensor: integrated electret microphone

Maximum sensitivity frequency: approximately 3kHz

Amplification: two stages with transistors (Q1, Q2)

Memory element: bistable flip-flop circuit (Q3, Q4)

Indicator: onboard LED for output state

Output connector: J2

Recommended load: 5V relay module or microcontroller digital input

Electronic schematic:

Pinout:

Instructions:

Connect the 5VDC supply to connector J1, observing the polarity marked on the board.

Check the initial state after power-up; the indicator LED should be off and the output should be LOW.

Clap once at a distance of 1 to 3 meters from the microphone and observe the LED turning on, at which point the output switches to 5V.

Clap again to return the output to LOW and turn off the LED.

To control a load, connect the OUT pin on J2 to the IN input of a 5V relay module and connect the grounds of the two modules together.

To integrate with a microcontroller, connect OUT to a digital input pin and GND to the board ground, using level shifting to 3.3V where applicable.

Place the module away from постоянные noise sources such as fans or speakers to avoid unwanted switching.

Test the response under real installation conditions before final mounting, because room acoustics affect the detection distance.

Warning: the module is powered at 5VDC and must never be connected directly to mains voltage. If the output controls a relay that switches 220VAC loads, the entire power side must be implemented by a qualified person, with proper isolation between the control side and the mains side, and work must be performed exclusively with the power disconnected from the distribution panel. Contact with mains voltage can cause electric shock or fire.