Sensor Digital

Microphone Sound Sensor Module

A KY-038 sound sensor module uses a microphone and threshold circuit to detect sound events.

Part images

KY-038 Module Photo. Module Photo for the KY-038 Microphone Sound Sensor Module. Image source: Joy-IT SensorKit KY-038 module documentation
KY-038 Pinout / Module Diagram. Pinout / Module Diagram for the KY-038 Microphone Sound Sensor Module. Image source: Joy-IT SensorKit KY-038 module documentation
KY-038 Arduino Wiring Diagram. Arduino Wiring Diagram for the KY-038 Microphone Sound Sensor Module. Image source: Joy-IT SensorKit KY-038 module documentation
KY-038 Raspberry Pi Wiring Diagram. Raspberry Pi Wiring Diagram for the KY-038 Microphone Sound Sensor Module. Image source: Joy-IT SensorKit KY-038 module documentation

What it is

A KY-038 sound sensor module uses a microphone and threshold circuit to detect sound events.

How students use it

Students use it for clap switches, noise-triggered lights, and threshold tuning practice.

Pins and power

Signal output, VCC, and GND on common KY-038 boards.

Use module power and output levels that are safe for Pico.

The digital output changes when sound level crosses the adjusted threshold.

Voltage and safety

Confirm the output is Pico-safe before wiring to GPIO.

Avoid loud test sounds that could hurt hearing.

Module internals

Main component: Electret microphone with threshold comparator.

Microphone capsule, comparator/trimmer, indicator LED, PCB, and header.

Datasheet notes

It is a sound trigger, not a microphone for recording audio.

Common libraries

Use machine.Pin for the digital output.

Common mistakes

Expecting speech recognition, placing it near buzzer feedback, ignoring room noise, and skipping threshold adjustment.