1. Sensor type: MEMS
2. Operating voltage: 3.0V~5.0V
3. Operating current: 17mA @3.3V
4. Detect alcohol (C₂H₅OH) concentration in the environment
5. Detection range: 0~400ppm (outputs A/D value)
   - Concentration level: 1~4 (default alarm level: 3)
6. Output mode: UART (baud rate: 9600bps) / STATUS
7. Factory-calibrated
8. Warm-up time: 180 seconds (default)
9. Dimension: 59.3 x 33.88 x 20 mm
10. Net weight: 10.8g

The product has the same functions as the BM22S3421-1. The difference between them is that the product breaks out the BM22S3421-1’s pins to match BMCOM connectors and can directly connect to BMduino development boards, such as BM53A367A and BM18B367A.
You can use the product with other development boards, such as Arduino UNO, as well.

There are four levels to range alcohol concentration from 1 to 4 (low to high).
The current concentration level, AD value, and alarm status can be outputted via UART interface every second. You can also monitor the STATUS pin to determine whether the alarm has been triggered. The voltage level turns high when alarming.

You can use commands to configure the alarm level and alarm exit level.

1. Alarm (default: level 3): when the product detects that the alcohol concentration in the environment has reached the alarm level for more than 3 seconds, the alarm will be triggered.
2. Exit alarm level (default: level 1): when the product detects that the alcohol concentration in the environment has reached the alarm exit level for more than 3 seconds, it exits alarm condition.

1. Place the product in the environment with the alcohol concentration that you desire for alarm.
2. Read the concentration level via UART interface.
3. And then configure this level as the alarm level.

For example, if you desire to trigger the alarm at a 350ppm alcohol concentration, place the product in an environment with a 350ppm concentration. Read the output concentration of 350ppm as level 4 via UART interface, and then configure level 4 as the alarm level.