Gas Sensor MQ135

The MQ135 Gas Sensor is designed for monitoring air quality and detecting harmful gases in the environment. It is commonly used in indoor air quality systems, pollution monitoring projects and smart automation applications. Thanks to its dual analog and digital outputs, it can be easily connected to Arduino, ESP32, Raspberry Pi and other development boards.

This sensor is a reliable and affordable solution for makers, students and developers who want to build air quality monitoring systems and environmental sensing projects.

Highlights:

• Detects: Ammonia (NH₃), NOx, Alcohol, Benzene, Smoke, CO₂ and other harmful gases.
• Analog Output: (A0) for continuous measurement.
• Digital Output: (D0) with adjustable trigger threshold.
• Onboard: LM393 comparator.
• Adjustable sensitivity: Via built in potentiometer.
• Fast response and recovery time.
• Easy integration with microcontrollers.

Specifications:

• Operating Voltage: 5V.
• Current Consumption: ~150mA.
• Output Type: Analog (A0) & Digital (D0).
• Detection Range: 10-1000 ppm (approx., depending on gas type).
• Preheat Time: 20-60 seconds recommended.
• Initial Burn in Time: 24-48 hours for stable calibration.
• Dimensions: ~32×20×22mm.
• Interface: 4-pin (VCC, GND, A0, D0).

Ideal For:

• 🏠 Smart home air quality systems.
• 🌍 IoT environmental monitoring stations.
  
• 🔬 Educational experiments.
  
• 🧪 DIY air pollution detection prototypes.
• 🎓 Arduino & STEM education projects.