Detect Carbon Monoxide with the MQ-7 Sensor Module

Ensure safety and monitor air quality with the MQ-7 Carbon Monoxide (CO) Gas Sensor Module. This high-sensitivity module is perfect for DIY electronics projects, alarms, and environmental monitoring systems. It features both analog and digital outputs, providing flexibility for your microcontroller, Arduino, or Raspberry Pi projects.

Key Features

• High Sensitivity: Reliably detects Carbon Monoxide (CO) concentrations from 10 to 1,000 ppm.
• Dual Output Mode:
  • AO (Analog Output): Provides a real-time voltage signal that increases with the CO concentration.
  • DO (Digital Output): A threshold-based output. When CO concentration exceeds a set point, the output goes LOW.
• Adjustable Sensitivity: An onboard potentiometer allows you to easily set the digital output (DO) trigger threshold.
• Status Indicators:
  • Power LED: Lights up when the module is powered.
  • DOUT LED: Lights up when the digital output is triggered (CO detected).
• Stable & Durable: Designed for long service life, stability, and fast recovery times.
• Easy Mounting: Features four screw holes for secure positioning in your project.

How It Works

This module is simple to integrate:

1. Power: Connect VCC to 5V and GND to Ground.
2. Analog Reading (AO): Connect the AO pin to an analog input on your microcontroller (like A0 on an Arduino) to get continuous concentration data.
3. Digital Alarm (DO): Connect the DO pin to a digital input. Use the blue potentiometer to adjust the sensitivity. When the CO level crosses the threshold, the DO pin will output a LOW signal, which can be used to trigger an alarm, LED, or relay.

Important MQ-7 Note: For the most accurate readings, the MQ-7 sensor requires a specific heating cycle: 5V (high) for 60 seconds and 1.5V (low) for 90 seconds. While the module can be operated at a constant 5V for basic detection, advanced users can implement this high/low voltage cycle for optimal performance as specified by the sensor's datasheet.

Specifications

• Gas Detected: Carbon Monoxide (CO)
• Detection Range: 10 - 1000 ppm (CO)
• Operating Voltage: 5V DC
• Heater Voltage (Sensor): 5V (High), 1.5V (Low)
• Outputs: Analog (AO) and Digital (DO)
• Comparator Chip: LM393
• Dimensions: 32mm x 20mm

Package Includes

• 1 x MQ-7 Carbon Monoxide (CO) Gas Sensor Module