DHT22 digital temperature and humidity sensor is a temperature and humidity composite sensor with calibrated digital signal output. The applied digital module acquisition technology and temperature and humidity sensing technology ensure the reliability and excellent long-term stability of the product. The sensor includes a resistive humidity sensor and an NTC temperature sensor, and is connected to a high-performance 8-bit single-chip microcomputer. DHT22 products are responsive and anti-interference. DHT11 sensors are calibrated in an accurate humidity calibration room. The calibration coefficient is stored in the OTP memory in the form of a program. The calibration coefficient is called inside the sensor during the processing of the detection signal. The single wire serial interface makes system integration simple and fast, small size, low power consumption, and signal transmission distance up to 20 More than meters.
DHT22 Description:
The starting signal of DHT22 is lowered by 800us. After the user host (MCU) sends a starting signal (lowering the data bus SDA by at least 800 µ s),AM2302 switches from sleep mode to high-speed mode. After the start signal of the host is completed, AM2302 sends a response signal and serially sends 40 bits of data from the data bus SDA, starting with the high-order bits of the byte; The data sent is in the order of humidity high, humidity low, temperature high, temperature low, and checksum. After sending the data, an information collection is triggered, and the sensor automatically enters sleep mode until the next communication arrives.
This module can be adapted to the D1 Mini development board for use.
Product parameters:
DHT22 Digital Temperature and Humidity Sensor
1. Power supply voltage: 3.3V
2. Signal output form: digital signal
3. Temperature measurement range:- 40℃~+80℃
4. Measurement accuracy: 0.5 ℃
5. Humidity measurement range: 0-99.9% RH
6. DHT22 measurement accuracy: 2% RH
7. DHT11 measurement accuracy: 4% RH
