MQ-3 High Sensitivity Alcohol Detector Sensor Module

MQ-3 High Sensitivity Alcohol Detector Sensor Module is designed to detect the presence of alcohol vapors in the air. With its high sensitivity and fast response time, it is ideal for breath analyzers, safety systems, and alcohol detection in embedded or standalone devices. The onboard comparator and adjustable threshold make it suitable for digital and analog interfacing with microcontrollers.

Key Features:

• High sensitivity to alcohol, ethanol, and smoke
• Fast response and recovery time
• Adjustable sensitivity via onboard potentiometer
• Analog and digital output support
• Power indicator and digital output LED onboard
• Simple interfacing with Arduino, Raspberry Pi, STM32, etc.

Technical Specifications:

• Detection Range: 0.05 mg/L to 10 mg/L Alcohol
• Operating Voltage: 5V DC
• Load Resistance: 200Ω to 10kΩ
• Heater Resistance: 31Ω ±3Ω
• Sensor Type: Semiconductor (SnO₂ based)
• Response Time: ≤10 seconds
• Operating Temperature: -10°C to 50°C
• Output: Analog (AO) and Digital (DO)

Mechanical Specifications:

• PCB Type: Dual-layer with soldered MQ-3 sensor
• Onboard Comparator IC: LM393
• Sensitivity Trimmer: Multi-turn potentiometer
• LED Indicators: Power (PWR) and Digital Output (DO)
• Connector: 4-pin header (VCC, GND, AO, DO)

Dimensions:

• Module Length: 32mm
• Module Width: 20mm
• Module Height: 22mm (including sensor dome)

Mounting Options:

• Mounting Holes: 2 x 3mm diameter at corners
• Compatible with: Breadboards, PCBs, enclosures, and panels
• Orientation: Vertical mount preferred for optimal sensing

Schematic Diagram, Connection, Wiring and Pinout:

• VCC: 5V DC input
• GND: Ground connection
• AO: Analog output voltage (proportional to gas concentration)
• DO: Digital output (high/low based on threshold)
• Wiring: Use jumper wires or headers to connect to microcontroller GPIOs

Datasheet/User Manual:

• MQ-3 Sensor Datasheet
• MQ-3 Arduino Example Code

Applications:

• Alcohol breath analyzer circuits
• Car alcohol detection and interlock systems
• Safety monitoring systems
• Consumer electronics and portable testers
• Industrial alcohol leak detection

Equivalent:

• MQ-303A: Higher sensitivity version for professional breath analyzers
• MQ-135: Multi-gas sensor (less accurate for alcohol but broader range)
• TGS 822: Similar alcohol detection range

Package Includes:

• 1 x MQ-3 High Sensitivity Alcohol Detector Sensor Module