MQ-135 Sensor Features

• Wide detecting scope
• Fast response and High sensitivity
• Stable and long life
• Operating Voltage is +5V
• Detect/Measure NH3, NOx, alcohol, Benzene, smoke, CO2, etc.
• Analog output voltage: 0V to 5V
• Digital output voltage: 0V or 5V (TTL Logic)
• Preheat duration 20 seconds
• Can be used as a Digital or analog sensor
• The Sensitivity of Digital pin can be varied using the potentiometer