The MQ-5 Methane LPG Liquid Propane Gas Sensor Module based on the MQ5 sensor IC as a gas sensing element. MQ-5sensor is ideal for detection or measuring of LPG, natural Gas & Town Gas at a range of 200-10000ppm. It offers very good sensitivity and fast response to LPG and also shows a small sensitivity to alcohol & smoke. It offers a wide range of applications in gas leakage detecting equipment in consumer and industry applications The module comes with basic components integrated allowing the sensor to function properly. And interfaced easily to any controller as the user prefers. Hence no external components required, we need to just plug in Vcc & ground pins and you are ready to go.
MQ5 module consists of both digital and analog outputs. This module not only provides a binary indication of the presence of combustible gases but also an analog representation of their concentration in air. When gas detected using the digital output, the indicator LED D0 turns ON. As a result, the digital pin will go from logic high to logic low 0V. The presence of onboard LM393 comparator IC compares the adjustable preset value and also eliminates the need for an external microcontroller. Simply power up the module and set the sensitivity of the digital pin using the potentiometer. So when the module detects the gas the digital pin will go low. MQ5 gas sensor module can be easily interfaced to any Microcontroller, Arduino, or even Raspberry Pi.
While using the analog pin to measure PPM, the TTL driven (0-5V) analog pins read values using a microcontroller that calculates the resistance value. By using the external load resistance the resistance variation converted into a suitable voltage variation. This will be directly proportional to the concentration of the gas to which the sensor detects.