Gravity: MQ9 Gas Sensor - CO & Combustible Gas Detector
MQ9-based SnO2 sensor detecting CO and combustible gases with analog output and adjustable sensitivity. Compatible with Arduino and other 5 V platforms via Gravity interface.
Pinout
- Output1
Gravity MQ9 analogue gas sensor output. DFRobot product specification states Output Signal: Analog (0-5V) and Pin Definition: 1-Output.
Type · AnalogVoltage · 0-5V analogue output per DFRobot product specification - VCC2
5V DC supply input. DFRobot product specification states Operating Voltage: 5V DC ±5% and Pin Definition: 2-VCC.
Type · PowerVoltage · 5V DC ±5% per DFRobot product specification - GND3
Ground reference. DFRobot product specification states Pin Definition: 3-GND.
Type · GroundVoltage · 0V
| Pin | Position | Type | Function | Voltage |
|---|---|---|---|---|
| Output | 1 | Analog | Gravity MQ9 analogue gas sensor output. DFRobot product specification states Output Signal: Analog (0-5V) and Pin Definition: 1-Output. | 0-5V analogue output per DFRobot product specification |
| VCC | 2 | Power | 5V DC supply input. DFRobot product specification states Operating Voltage: 5V DC ±5% and Pin Definition: 2-VCC. | 5V DC ±5% per DFRobot product specification |
| GND | 3 | Ground | Ground reference. DFRobot product specification states Pin Definition: 3-GND. | 0V |
Pin details
3 connections- Output1
Gravity MQ9 analogue gas sensor output. DFRobot product specification states Output Signal: Analog (0-5V) and Pin Definition: 1-Output.
AnalogVoltage · 0-5V analogue output per DFRobot product specification - VCC2
5V DC supply input. DFRobot product specification states Operating Voltage: 5V DC ±5% and Pin Definition: 2-VCC.
PowerVoltage · 5V DC ±5% per DFRobot product specification - GND3
Ground reference. DFRobot product specification states Pin Definition: 3-GND.
GroundVoltage · 0V
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. Schematik maps them to your board in the app.
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