DHT22 AM2302 Digital Humidity and Temperature Sensor
DHT22 AM2302 Digital Humidity and Temperature Sensor is a basic, low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed). Its fairly simple to use, but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds, so when using our library, sensor readings can be up to 2 seconds old.
Each AM2302 sensors are extremely precise humidity calibration chamber for calibration. The calibration coefficients stored in the form of a program OTP memory, internal sensor, the detection signal process to call these calibration coefficients. Single wire serial interface, system integration becomes quick and easy. Ultra-small size, low power consumption, signal transmission distance up to 20 meters, making it is the best choice for all kinds of applications and even the most demanding applications. The product is a 4-pin single row pin package. Easy connection, special packages according to user needs.
Simply connect the first pin on the left to 3-5V power, the second pin to your data input pin and the right most pin to ground. Although it uses a single-wire to send data it is not Dallas One Wire compatible! If you want multiple sensors, each one must have its own data pin!
Compared to the DHT11, this sensor is more precise, more accurate and works in a bigger range of temperature/humidity, but its larger and more expensive
Comes with a 4.7K - 10K resistor, which you will want to use as a pullup from the data pin to VCC.
- Voltage: 3 to 5V power and I/O
- Current: 2.5mA max current use during conversion (while requesting data)
- Humidity Range: Good for 0-100% humidity readings with 2-5% accuracy
- Temperature Range: -40 to 80°C temperature readings ±0.5°C accuracy
- Sampling rate: No more than 0.5 Hz (once every 2 seconds)
- 4 pins, 0.1" spacing