DHT11 temperature & humidity module
DHT11 module · 0–50 °C ±2 °C · 20–90 % RH ±5 % · whole numbers only · 3.3–5.5 V · one data wire with the board's 10 kΩ pull-up · at most one reading per second · now 28 °C, 60 % RH
Try it on the benchThe lab drops it on an empty bench and opens its datasheet card.
Pins
- VCC
- DATA
- GND
What it is
The DHT11 module is the blue three-pin board with the DHT11 sensor, a 10 kΩ pull-up on the data line and a power LED. It measures 0–50 °C and 20–90 % relative humidity, in whole numbers only, and answers on one data wire after the microcontroller pulls the line low for at least 18 ms.
What to check before you buy or wire it
- Supply: 3.3–5.5 V. The pull-up is already on the board, so no extra resistor is needed.
- Read it at most once a second. In the sketch use DHT dht(pin, DHT11); the DHT22 setting decodes the bytes the wrong way and gives nonsense values.
Common mistakes
- Choosing DHT22 in the sketch for a DHT11 (or the other way round).
- Expecting decimals or readings below 0 °C: the DHT11 gives whole numbers from 0 to 50 °C.
Where it is used
Room and greenhouse monitors, first weather-station projects, and fan or humidifier control where ±2 °C is good enough.