Analog Gas Sensor(MQ3) (SKU:SEN0128)

From DFRobot Electronic Product Wiki and Tutorial: Arduino and Robot


The analog gas sensor - MQ3 is suitable for detecting alcohol, this sensor can be used in a Breathalyser.It has a high sensitivity to alcohol and small sensitivity to Benzine. The sensitivity can be adjusted by the potentiometer.


  • Power supply needs: 5V
  • Interface type: Analog
  • Pin Definition: 1-Output 2-GND 3-VCC
  • High sensitivity to alcohol and small sensitivity to Benzine
  • Fast response and High sensitivity
  • Stable and long life
  • Simple drive circuit
  • Size: 40x20mm

Pin Definition

  1. Signal Output
  2. GND
  3. Power
Analog Sensor Pin Definition

Connection Diagram

Analog sensor connection diagram

Sample Code

///Arduino Sample Code
void setup()
  Serial.begin(9600); //Set serial baud rate to 9600 bps
void loop()
int val;
val=analogRead(0);Read Gas value from analog 0
Serial.println(val,DEC);//Print the value to serial port

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Category: DFRobot > Sensors & Modules > Sensors > Air Sensors