Analog CO / Combustible Gas Sensor (MQ-9)

The MQ-9 Analog Gas Sensor Module is designed for detecting gas leaks in home and industrial environments. It utilizes an SnO2 (tin oxide) sensitive material that offers high sensitivity to carbon monoxide (CO), methane (CH4), and liquefied petroleum gas (LPG).

This module is ideal for building gas leak alarms or environmental monitoring systems connected to microcontrollers like Arduino or Raspberry Pi. The analog output allows for reading approximate gas concentration trends, while the digital output provides a threshold signal adjustable via the onboard potentiometer.

Specifications

• Target Gases: Carbon Monoxide (CO), Methane (CH4), LPG
• Supply Voltage: 5V DC
• Outputs: Analog (AOUT) and Digital (DOUT)
• Detection Range: 100 to 10,000 ppm
• Response Time: ≤ 1 second
• Recommended Pre-heat: ≥ 24 hours for optimal stability
• Onboard Potentiometer for digital threshold adjustment

Note: This sensor provides an approximate trend of gas concentration. For precise quantitative measurements, a professional instrument is recommended.