Gasdetector
ENS160 + AHT21
This module combines two sensors on one module making it very easy to connect to.
The ENS160 is an digital four channel MOX gas sensor with I2C interface.
| Pin | Gebruik | |
|---|---|---|
| 1 | Vin | |
| 2 | 3V3 | 3,3 V |
| 3 | GND | Massa |
| 4 | SCL | I2C clock |
| 5 | SDA | I2C data |
| 6 | AD0 | Address GND = 0x52, 3.3 = 0x53 |
| 7 | CS | Communication interface Select (CS low -> SPI / CS high -> I>sup>2 |
| 8 | INT | Interrupt out |
Startup and Calibration
The ENS160 needs to be powered on for one hour for the initial startup calibration to happen but it needs to be continuously powered for 24 hours for that calibration to persist (writen to the onboard non-volatile memory).
After the initial 24 hour calibration, then it should take about 3 minutes to startup. Ref the datasheet.
Temperature
It is also worth mentioning that this sensor module is made from two differend sensors, the END160 and the ATH21, on the same device.
The ENS160 is a sensor that requires a certain heating to work, and it will heat itself up to the desired temperature. This can cause the temperature reading as measured by the ATH21 to be a few degrees higher than the ambient temperature. If your intention is to use the ENS160 + ATH21 as a temperature sensor, then factor in a possible offset.
MQ-135
This sensor detects a number of gases so that air quality in general can be measured. The sensor has both an analog and a digital output.