MQ-135 Sensor Air Quality Sensor Hazardous Gas Detection Module

75.00 EGP

A highly sensitive electromechanical sensor unit for monitoring air quality and detecting toxic gases and pollutants in the surrounding environment. It relies on tin dioxide ($SnO₂), a material with low conductivity in clean air, whose electrical conductivity automatically increases with the concentration of polluting gases. Technical Specifications: Operating Voltage: 5V DC. Detectable Gases: Ammonia ($NH₃), Nitrogen Oxides ($NO), Alcohol, Benzene Vapors, Smoke, and Carbon Dioxide ($CO₂). Detection Range: 10 ppm to 1000 ppm (depending on the gas type). Dual Output Options: Analog Output (AO): Provides a voltage directly proportional to the gas concentration for accurate ratio calculation. Digital Output (DO): Provides a simple digital signal (0 or 1) via the LM393 comparator chip when the gas concentration exceeds a certain threshold. Potentiometer: Allows you to adjust the sensitivity threshold of the digital output according to the environment. LED Indicators: Power indicator. Another indicator lights up as soon as the digital output is activated upon detecting pollutants. Connection terminals (4 pins): VCC: Power supply (5V). GND: Ground (0V). DO: Digital output signal to the microcontroller. AO: Analog output signal to the ADC input.