MQ-3 Gas Sensor (Waveshare 9530)

Overview

• Sensitive for alcohol, ethanol
• Output voltage boosts along with the concentration of the measured gases increases
• Fast response and recovery
• Adjustable sensitivity
• Signal output indicator

Specifications

• Power: 2.5V ~ 5.0V
• Dimension: 40.0mm * 21.0mm
• Mounting holes size: 2.0mm

Applications

• Car alcohol alarm
• Breathalyser

How to Use

In the case of working with a MCU:

• VCC ↔ 2.5V ~ 5.0V
• GND ↔ power supply ground
• AOUT ↔ MCU.IO (analog output)
• DOUT ↔ MCU.IO (digital output)

Photos

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Downloads

Development resources: demo codes, schematic, datasheets, etc.
Wiki: www.waveshare.com/wiki/MQ-3_Gas_Sensor

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Selection Guide

Part Number	Sensitive Gas	Application
MQ-135 Gas Sensor	benzene, alcohol, smoke	Air quality monitor
MQ-2 Gas Sensor	LPG, propane, hydrogen	Gas leakage detector
MQ-3 Gas Sensor	alcohol, ethanol	Car alcohol alarm, breathalyser
MQ-5 Gas Sensor	LPG, natural gas, coal gas	Gas leakage detector
MQ-7 Gas Sensor	carbon monoxide	Carbon monoxide monitor