To create Arduino based device to compare data for as much t/RH sensors as possible (without manual sensor switch), optionally with data logging for further analysis.
Use of same sensor on i2c usually limited by 1 or 2 (using ALT i2c address) of same type. And SHT20, SHT21, SHT25, HTU21 is actually same type, so to be able to compare measurement there is need to use i2c multiplexer. In case of 8 line multiplexer there is possibility to have 8-16 sensor of same time to be connected with Arduino.
to divide between multiplexers
Sensor | address | alt address | spec | Vmin-Vmax | Vtyp | 3.3v | 5v** |
---|---|---|---|---|---|---|---|
AOSONG AHT10 | 0x38 (62) | 0x39 (63) | 1.8-3.6v | 3.3v | |||
Senserion SHT2x | 0x40 (64) | 0x41 (65) | 20,21,25 | 2.1-3.6v | 3v | ||
Senserion SHT3x | 0x44 (68) | 0x45 (69) | SHT3x | 2.15-5.5v | 3.3v | ||
Senserion SHT8x | 0x44 (68) | SHT85 | 2.15-5.5v | 3.3v | |||
Meas(1) HTU21D | 0x40 (64) | HTU21D | 1.5v-3.6v | 3v | |||
Silicon Labs Si7021 | 0x40 (64) | 1.9v-3.6v | - | ||||
Bosch(2) BMEx80 | 0x76 (118) | 0x77 (119) | 680 | 1.71v-3.6v | 1.8v | ||
Bosch(2) BME280 | 0x76 (118) | 0x77 (119) | 280 | 1.71v-3.6v | 1.8v | ||
Ti(3) HDC1080 | 0x40 (64) | 2.7v-5.5v | 3v | ||||
AOSONG DHT12 | 0x5C (92) | 2.7-5.5v | 5v | ||||
AOSONG AM2320 | 0x5C (92) | 0xB8 ? | 3.1-5.5v | 5v |
1 TE Connectivity Measurement Specialties
2Bosch Sensortec
3 Texas Instruments
** some sensors board have voltage regulators and level converter (and may support voltages above mentioned in sensor datasheet)