Documentation: Usage of 1-wire temperature sensors
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heinemannj commented
Usage of 1-wire temperature sensors (DS18B20):
https://esphome.io/components/sensor/dallas.html
"... The 1-Wire bus ... should have an external pullup resistor of about 4.7KΩ. ..."
"... For this, connect a resistor of about 4.7KΩ between 3.3V and the data pin. ..."
"... Values ± 1KΩ will, in most cases, work fine as well, if you don’t have massively long wires. ..."
| 1-Wire Bus | Board | DS18B20 | Resistor |
|---|---|---|---|
| Power | VCC (3.3. V) | red | ~4.7KΩ between Power and Data |
| Ground | GND | black | - |
| Data | IO (e.g. IO22) | yellow | ~4.7KΩ between Power and Data |
See:
https://github.com/nliaudat/esp32_8ch_motor_shield/blob/main/extension.md
Note:
With proper and short cabling more than 16 DS18B20 on the same 1-wire bus seems to be possible.