The DHT22 is a small sensor ( named as AM2302 ) .
The function of this product is Humidity & Temperature sensor.
Manufacturers : Aosong Electronics
DHT22 Datasheet learn more.
Image :
DHT22 Pinout
1 pin : VDD : power supply
2 pin : DATA : signal
3 pin : NULL
4 pin : GND
Description :
DHT22 output calibrated digital signal. It utilizes exclusive digital-signal-collecting-technique and humidity sensing technology, assuring its reliability and stability.Its sensing elements is connected with 8-bit single-chip computer.
Every sensor of this model is temperature compensated and calibrated in accurate calibration chamber and the calibration-coefficient is saved in type of programme in OTP memory, when the sensor is detecting, it will cite coefficient from memory. Single-row packaged with four pins, making the connection very convenient.
DHT22 arduino
Technical Specification
1. Power supply : 3.3-6V DC
2. Output signal : digital signal via single-bus
3. Sensing element : Polymer capacitor
4. Operating range : humidity 0-100%RH; temperature -40~80Celsius
5. Accuracy : humidity ± 2%RH(Max ± 5%RH); temperature < ±0.5Celsius
6. Resolution or sensitivity : humidity 0.1%RH; temperature 0.1Celsius
7. Repeatability humidity : ± 1%RH; temperature ± 0.2Celsius
8. Humidity hysteresis : ± 0.3%RH
9. Long-term Stability : ±0.5%RH/year
10. Sensing period : Average: 2s
11. Interchangeability : fully interchangeable
12. Dimensions small : size 14*18*5.5mm; big size 22*28*5mm
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Applications and Features
1. High precision
2. Capacitive type
3. Full range temperature compensated
4. Relative humidity and temperature measurement
5. Calibrated digital signal
6. Outstanding long-term stability
7. Extra components not needed
8. Long transmission distance, up to 100 meters
9. Low power consumption
10. 4 pins packaged and fully interchangeable
Reference site
1. Overview | Sensors | Adafruit Learning System
Please refer to the file for details.
DHT22 Datasheet
