The MQ4 Sensor is highly sensitive to methane and natural gas and also has a small sensitivity to alcohol and smoke. This sensor has both analog and digital output and a potentiometer for setting the trigger threshold.

Features:

It adopts high quality double panel design with power indication and TTL signal output indication
It has DO switch signal (TTL) output and AO analog signal output
The TTL output valid signal is low (When the output is low the signal light is on it can be directly connected to the MCU or relay module)
The voltage of the analog output the higher the concentration the higher the voltage
It has good sensitivity to gas and natural gas detection
There are four screw holes for easy positioning
Has a long service life and reliable stability
Fast response recovery characteristics