MQ7 GAS SENSOR
The MQ-7 gas sensor is specifically designed to detect carbon monoxide (CO). It's widely used in safety systems for homes and industries to monitor CO levels and prevent potential hazards.
Features: Gas Sensor module MQ7
Sensitive for carbon monoxide
Output voltage boosts along with the concentration of the measured gases increases
Fast response and recovery
Adjustable sensitivity
Signal output indicator
Specifications: Gas Sensor module MQ7 – ADIY
2.5V TO 5V operation
LEDs for output and power
Output sensitivity adjustable
Analog output 0V to 5V
Digital output 0V or 5V
Low Cost
Fast Response
Stable and Long Life
Both Digital and Analog Outputs
Dimension: 40.0mm * 21.0mm
Mounting holes size: 2.0mm
VCC ↔ 2.5V ~ 5.0V
GND ↔ power supply ground
AOUT ↔ MCU.IO (analog output)
DOUT ↔ MCU.IO (digital output)
Detection Range: 20 to 2000 ppm.
Operating Temperature: -10°C to 50°C.
Working Principle
SnO₂ Sensing Layer: When CO gas comes into contact with the heated surface, it reduces the sensor's resistance.
Resistance Changes: As CO concentration increases, the sensor's resistance decreases, generating a corresponding voltage.
Heating Cycle: For accurate readings, the sensor requires two phases:
60 seconds at 5V: Cleaning cycle (high heat).
90 seconds at 1.4V: Measurement cycle (low heat).
Applications
Carbon Monoxide Detectors: For homes and industries.
Smart Home Safety Systems: Integrated into IoT devices.
Automotive Systems: Detecting exhaust gas leaks.
Industrial Monitoring: CO detection in factories and warehouses.
