Gas detection, air quality module

Model: MQ-135.
Gas detection, air quality module.
This air quality control sensor is used to detect pollution in the environment, it is generally implemented in control circuits such as alarms in homes, places where it is desired to prevent high levels of pollution at an aerobic level, such as industries that They handle chemical compounds that can also be harmful to health, especially in air quality control equipment in buildings/offices.
This sensor is responsible for detecting gas concentration in various percentages, just like its MQ-3/4/5 analogues. The output signal provided by the MQ-135 is dual, analog and digital. Regarding the analog signal provided, this becomes directly proportional to the increase in voltage. The digital signal has TTL levels so this signal can be processed by a microcontroller.

Specifications:
Operating voltage: 5 V DC.
Operating current: 150 mA.
Consumption power: 800 mW.
Preheat time: 20 seconds.
Load resistance: potentiometer (adjustable).
Parts per million detection: 10ppm~1000ppm.
Detectable concentration: ammonia, sulfur, benzene, smoke.
Oxygen concentration: 2%~21%.
Operating humidity: <95%RH.
Operating temperature: -20°C~70°C.