Sensitive material MQ-3 gas sensor is used in clean air low conductivity tin oxide (SnO2). When there is alcohol vapor in the environment sensor, conductivity sensor with increasing gas concentration of alcohol in the air increases. Use simple circuit can convert the change in conductivity of the gas concentration corresponding to the output signal. High MQ-3 gas sensor sensitivity to alcohol, can resist the interference of gasoline, smoke, water vapor. The sensor can detect a variety of alcohol concentration in the atmosphere, is a low-cost sensor suitable for a variety of applications.
For on-site detection of motor vehicle drivers and other non-drinking workers, but also for detecting other places of ethanol vapor, alcohol detection range: detection range 10 ~ 1000 ppm.
Note:
VCC: positive power supply (5V)
GND: power supply is negative
DO: TTL switching signal output
AO: analog signal output