Gas Sensor MQ135

This module is made for Air Quality detection. You may use this module with 5v. You may integrate this module with different projects that have air quality monitoring in it. This module is sensitive to gases namely NH3(Ammonia), NOx (Nitrogen Oxide), Alcohol, Benzene, Smoke, and CO2 (Carbon Dioxide). This has 4 pins (Digital Pin, Analog Pin, VCC, GND) but you will only need three (either D or A) to operate.

SPECIFICATIONS:

• Working voltage:DC 5V
  
• Working Current: 150mA
  
• DOUT: TTL output
  
• AOUT: Analog output
  
• Preheat time: Over 20s
  
• Dimension: 32mm x 22m x 27mm(HIGH 27mm)