MQ9 Gas Sensor Module

Product details The MQ9 Gas Sensor Module is a versatile semiconductor-based gas detection device optimized for sensing carbon monoxide and various combustible gases. The core sensing element contains a tin dioxide (SnO₂) layer that changes resistance depending on the concentration of target gases, enabling measurement of gas levels with high sensitivity. The module includes both an analog output for precise concentration monitoring and a digital output driven by an onboard LM393 comparator. An adjustable potentiometer allows threshold configuration for digital triggering. Operating at 5V DC, the MQ9 supports rapid response, wide detection range, and stable performance, making it suitable for safety-critical applications such as leakage alarms, industrial gas monitoring, and smart IoT systems.