Gas Sensor MQ-7 Sensitive Carbon Monoxide Gas

MQ7 is a semiconductor sensor which can detect the presence of carbon monoxide gas at concentrations from 20 to 2000 ppm. The sensitive material used for this sensor is SnO₂, whose conductivity is lower in clean air. It’s conductivity increases as the concentration of carbon monoxide gas increases. It makes detection by method of high (5V heating) and low (1.4V heating) temperature. It can detect CO during low-temperature heating. When high-temperature heating is employed, it cleans other gases adsorbed under low temperature. MQ7 Carbon monoxide gas sensor can be easily interfaced with Microcontrollers, Arduino Boards, Raspberry Pi etc using an Analog to Digital Converter (ADC).

Applications

• Domestic gas leakage detector
• Industrial CO detector
• Portable gas detector

Features

• Low Cost
• High Sensitivity to Carbon monoxide
• Stable and Long Life
• Simple drive circuit

Technical Data

• Circuit Voltage : 5V ±0.1 AC or DC
• Heating Voltage High : 5V ±0.1 AC or DC
• Heating Voltage Low : 1.4V ±0.1 AC or DC
• Load Resistance : Adjustable
• Heater Resistance : 33Ω ±5% at Room Temperature
• Heating Consumption : < 350mW
• Operating Temperature : -20°C ~ 50°C
• Detection Range : 20 ~ 2000 ppm of carbon monoxide
   
• Operating Voltage: DC 5V
• Analog Output (AO): 0~5V analog output voltage
• Digital Outout (DO): 0V or 5V output
• Configuration: Through Potentiometer (adjusts the output level transition)
• Preheat Duration: 20s
• Weight: 5g
• Dimensions: 23 x 19 x 19 mm

Datasheet

• MQ7 Carbon monoxide Sensor Datasheet