DHT22 Humidity and Temperature Sensor Module (AM2302)

What It Is

• The DHT22 (also called AM2302) is a digital temperature and humidity sensor that uses a capacitive humidity sensing element and a thermistor to measure the environment and output calibrated digital readings.

• It's an upgrade over DHT11 offering wider range and better accuracy.

Key Features

Digital Output: Sends temperature and humidity data over a single digital data line no analog conversion needed. Wide Temperature Range: Measures from about 40C to +80C. Wide Humidity Range: From 0% to 99.9% relative humidity. High Accuracy: Temperature: about 0.1C (temp) and 0.1% RH (humidity) Power Supply: Typically 3.3V to 5.5V DC, suitable for Arduino, Raspberry Pi, ESP32, etc. Low Power Consumption: Good for battery'powered systems.

How It Works

• The module reads temperature and humidity with internal sensors and outputs digital data in a simple protocol.

• Only one pin (data) is used for communication with your controller but it's not Dallas One'Wire compatible, so each sensor needs its own data pin in multi'sensor setups.

• Updates are available roughly once every 2 seconds (about 0.5Hz sampling rate).

Typical Applications

Weather Stations & Environmental Monitoringms Greenhouse & Agriculture Climate Monitoring IoT Devices and Smart Sensors Consumer Electronics & Appliances

Important Notes

Sampling Limitation: You can request new readings only about once every 2 seconds. Careful Timing: Code must handle timing correctly to read data. Environmental Limitations: Direct water or heavy condensation contact can affect humidity performance sensors are best used where moisture won't settle directly on them. Better Alternatives: For higher accuracy and fast