MQ-4 Gas Sensor Module D-Type 3V and 5V (both power

3V and 5V (both power output and IO level)

It is an ON-ON type switch that can be used as a general-purpose ON/OFF switch

Brown for these 33E resistors

OPDO pin is open drain output

MQ-4 Gas Sensor Module D-Type 3V and 5V (both powerThis MQ4 Methane Gas sensor module can sense the presence of compressed Natural Gas sensors (CNG), methane(CH4) etc. in the air. This is a very easy to use low cost semiconductor Gas sensor Module with analog and digital output. It requires no external components just plug in VCC & ground pins and you are ready to go. It is small sensitive to alcohol and smoke. This module has an IC LM393 is a dual differential comparator; this means that it accepts 2