Microphone Sound Sensor(KY-038)

This module detects the intensity of sound and changes the output voltage according to the ambient sound level, outputting it as an analog signal.

It is similar to the KY-037 model.

Specifications

• Operating Voltage [V]: 3.3 ~ 5
• Frequency Range [Hz]: 50 ~ 20K

Example Usage Hardware

• Arduino board
• Jumper cables
• KY-038 Sound Detection Sensor

Connection

Although the digital pin is not used in this example, please refer to it as a connection example.

When using the KY-038 module digitally, supply power to the module in a quiet environment and then adjust the sensitivity by turning the variable resistor.

Arduino Uno	KY-038
5V	+
GND	G
D8	DO
A0	AO

Example Code

This example turns on the internal LED (pin 13) of the Arduino when sound is detected and then turns it off after a certain period.

int analogPin = A0;
int ledPin = 13;
int analogVal = 0;
long int past_time = 0;
int past_analogVal = 0;

void setup() {
  pinMode(analogPin, INPUT);
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, HIGH);
  Serial.begin(9600);
}

void loop() {
  analogVal = analogRead(analogPin);
  if (millis() - past_time > 1000) {
    if (abs(past_analogVal - analogVal) > 3) {
      digitalWrite(ledPin, !digitalRead(ledPin));
      past_analogVal = analogVal;
      past_time = millis();
    }
  }
  delay(10);
}