Summary
Highlights
The DHT11 measures temperature from 0°C to 50°C with ±2°C accuracy and humidity from 20% to 80% with 5% accuracy. It has a sampling rate of 1 Hz, providing new data every second. It typically requires a 10k pull-up resistor on the output pin and includes a decoupling capacitor.
Inside the DHT11, you'll find an 8-bit microcontroller for data processing. On the PCB, there's an NTC thermistor and a humidity-sensing component.
The humidity sensing component has two electrodes with a moisture-holding substrate. As humidity increases, the substrate absorbs water, releasing ions and decreasing resistance between the electrodes. This resistance change is proportional to humidity.
This video will demonstrate how the DHT11 sensor works with Arduino to measure temperature and humidity.
The DHT11 uses an NTC thermistor for temperature measurement. An NTC thermistor's resistance decreases as temperature rises, which is how it measures temperature.
The DHT11 has a VCC pin for power (3.3V to 5.5V), an Out pin for communication with the microcontroller, and a GND pin for ground. The video provides a diagram for wiring the DHT11 module to an Arduino.