The sensor determines the concentration of alcohol in the air, the result can be obtained measuring the voltage on the analog output. The system ispowered with the voltage from 2.5 V to 5 V. Ithas a digital and analog output, making it compatible with mostof the commissioning modules includingRaspberry Pi and Arduino.

The digital output D0

With the help of placed on the reverse side of theboard,potentiometer,set isthe threshold, exceeding of which, causesthe output D0 changing from a high to a low status. Thepin D0 can be linked directly with a microcontroller or commissioning set, includingArduino, or for example,a module with a buzzer, which will signala too low or too high levelof alcohol in the air.

Analog output A0

The sensor has an analog output A0, which must be connected to thepin of the converter A/D (analog input inArduino). This will allow you to measure the proportional voltage signal and more accurately determine the level of alcohol.

Operating principle:
MQ-3 gas sensor applies SnO2 which has a lower conductivity in the clear air as a gas-sensing material. In an atmosphere where there may be alcohol gas, the conductivity of the gas sensor raises along with the concentration of the alcohol gas increases.

Features:

1. Sensitive for alcohol, ethanol
2. Output voltage boosts along with the concentration of the measured gases increases
3. Fast response and recovery
4. Adjustable sensitivity
5. Signal output indicator

Specification:

1. Power supply: from 2.5 V to 5 V
2. Analog and digital output
3. Pins: goldpin connectors, 2.54 mmpitch
4. Boardsizes: 40 x 21 mm
5. It hasmounting holeswith thediameter: 2 mm

Package Includes:

1 x MQ-3 Gas Sensor
1 x 4-pin custom connector jumper wire