MQ-2 Gas Sensor
Resistive MQ-2 sensor for detecting LPG, propane, hydrogen, smoke, and other combustible gases; outputs an analog voltage.
Pinout
- AOUT1
analog output
Type · Analog - DOUT2
digital threshold output
Type · GPIO - GND3
ground
Type · Ground - VCC4
supply
Type · Power
| Pin | Position | Type | Function |
|---|---|---|---|
| AOUT | 1 | Analog | analog output |
| DOUT | 2 | GPIO | digital threshold output |
| GND | 3 | Ground | ground |
| VCC | 4 | Power | supply |
Pin details
4 connections- AOUT1
analog output
Analog - DOUT2
digital threshold output
GPIO - GND3
ground
Ground - VCC4
supply
Power
Start wiring
I2C · Analog · UART · 3.3 – 5 V · Breakout
Waveshare lists MQ-2 for combustible gases and smoke, MQ-3 for alcohol, and MQ-135 for mixed indoor pollutants such as NH3, NOx, alcohol,…
Module pins: VCC, GND, AOUT, DOUT. Schematik maps them to your board in the app.
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