MQ 7 Gas Sensor for Arduino/Raspberry Pi
The MQ 7 Gas Sensor for Arduino/Raspberry Pi is a highly sensitive carbon monoxide detection module. It provides reliable CO concentration measurement with both analog and digital outputs for safety monitoring applications.
Key Features
- High sensitivity to carbon monoxide (CO) gas
- Dual output – analog and digital for flexible interfacing
- Adjustable sensitivity via onboard potentiometer
- Fast response and recovery characteristics
- Long lifespan with stable performance
- 5V operation compatible with Arduino and Raspberry Pi
- Compact module for easy integration
Technical Specifications
| Parameter |
Specification |
| Model |
MQ-7 |
| Operating Voltage |
5V DC |
| Output Type |
Analog + Digital |
| Detectable Gas |
Carbon Monoxide (CO) |
| Detection Range |
20-2000 ppm |
| Preheat Time |
48 hours (first use) / 60 seconds (cycle) |
| Operating Temp |
-10°C to +50°C |
| Heater Voltage |
1.5V ± 0.1V (alternating) |
Applications
- Carbon monoxide alarms and safety systems
- Industrial CO monitoring in workshops
- Garage and parking ventilation control
- Home safety monitoring systems
- Environmental CO tracking
- Smart building automation with gas detection
Pinout
- VCC: 5V Power supply
- GND: Ground
- A0: Analog output (0-5V proportional to CO concentration)
- D0: Digital output (HIGH when CO detected above threshold)
Important Notes
- Requires alternating 5V/1.5V heater voltage for accurate readings
- 48-hour initial burn-in required for stable operation
- Sensitive to temperature and humidity – calibrate accordingly
- Not a certified safety device – for hobby/educational use
- Digital output threshold should be set after calibration
