Microphone Sound Detection Module LM393

Features:

• Operating Voltage: DC 3.3V - 6V
• IC Chip: LM393 Dual Comparator
• Output Type: Digital signal (LOW when sound detected)
• Adjustable Sensitivity: Onboard potentiometer for fine-tuning threshold
• Signal Indicator: Onboard LED lights up when sound exceeds setpoint
• Mounting: Bolt hole for easy attachment to cases or panels
• Single Channel Output: Processes input from a single microphone

Principle of Operation:

1. Microphone: Detects ambient sound waves and converts them to a weak analog voltage signal.
2. Amplification: LM393 amplifies the weak signal for comparison.
3. Threshold Setting: Adjustable potentiometer sets the voltage threshold level.
4. Comparison: The LM393 compares the signal from the microphone to the threshold value.
5. Digital Output: If the sound exceeds the threshold, output goes LOW (0V), triggering the LED.

Pinout:

Applications:

• Clap-activated switches
• Voice-controlled systems
• Animal sound detection
• Noise monitoring or alarms
• Interactive sound-reactive installations

Circuit Diagram:

Example wiring to an Arduino UNO:

• OUT → Pin 2 (Digital Input)
• VCC → 5V
• GND → GND
• LED → Pin 4 (via 220Ω resistor)

Arduino Code Example:

const int ledPin = 4;
const int microphonePin = 2;
int state = LOW;

void setup() {
  pinMode(ledPin, OUTPUT);
  pinMode(microphonePin, INPUT);
  Serial.begin(9600); // Start serial communication
}

void loop() {
  state = digitalRead(microphonePin);
  Serial.print("Microphone state: ");
  Serial.println(state);

  if (state == HIGH) {
    digitalWrite(ledPin, HIGH);
    Serial.println("LED ON");
    delay(1000);
  } else {
    digitalWrite(ledPin, LOW);
    Serial.println("LED OFF");
  }

  delay(100); // Avoid flooding the serial monitor
}

Technical Specifications:

Resources:

• Tutorial 1 – Getting Started with LM393

Comparison with KY-037 Module: