MQ3 Alcohol Sensor Detector Gas Sensor Module


MQ-3 Alcohol Detector Gas Sensor Module is a simple to use MQ-3 Alcohol Detector Gas Sensor Module which can sense the presence of Alcohol in the air. The module uses our MQ-3 sensor. It simplifies the interface to the odd pin spacing of the sensor and provides an interface through standard 4 x 0.1″ header pins. It provides an analog output corresponding to the concentration of the gas in the air and an easy-to-use digital output.

The onboard potentiometer can be used to set the maximum gas concentration beyond which the digital output gets triggered. Just power the module with 5V set the threshold and you can start getting the gas concentration of the air around the sensor! An onboard LED signals the presence of any gas. Perfect sensing alcohol concentration on your breath just like a common breathalyzer.


  • Signal output light indicator
  • Analog and level signal output
  • TTL output valid signal is low. (When the output low signal light can be directly connected microcontroller or relay module)
  • The carbon monoxide detection with better sensitivity
  • Has a long service life and reliable stability
  • Rapid response recovery features


Pin NamePin Description
VCC is the Gas Detection Sensor’s power supply pin, which can be linked to a 5V source.
GND is the board’s ground pin, which should be linked to the Arduino’s ground pin.
DOUT is the board’s digital output pin; a low output indicates that no alcohol is present in the environment, while a high output indicates that Alcohol is present?
AOUT is the board’s Analog output pin, which will provide us with an analog signal that varies between Vcc and ground depending on the alcohol level detected


Model NoMQ-3
Dimensions36 x 20 x 21 mm (LxWxH)
Heater voltage5±0.2V (AC•DC)
Loop voltage≤24V (DC)
Load resistanceAdjustable
Heating Resistance31Ω±3Ω (Room temperature)
Heating Power≤ 900mW
Surface thermal resistance2Kohm-20Kohm (0.4mg/L alcohol)
SensitivityRs (in air)/Rs (0.4mg/L alcohol) ≥ 5
Working temperature20 degrees ±2 degree


  • Breathalyzer devices: The MQ3 Alcohol Sensor Detector Gas Sensor Module is commonly used in breathalyzer devices for measuring alcohol levels in a person’s breath. It can be integrated into portable breathalyzer devices or alcohol monitoring systems for personal or law enforcement use.
  • Safety systems: The module can be employed in safety systems to detect alcohol levels in environments where alcohol consumption may pose a risk, such as in factories, chemical plants, or transportation vehicles. It can trigger alarms or safety protocols when high alcohol concentrations are detected.
  • Automotive applications: The module can be integrated into automotive systems for alcohol detection. It can be used in ignition interlock devices that prevent a vehicle from starting if the driver’s alcohol level exceeds a certain threshold, promoting safe driving practices.


Download the Datasheet of MQ3 Alcohol Sensor Detector Gas Sensor Module from the link given below.