DFRobot Gravity DHT22 Temperature & Humidity Sensor Module

The DFRobot Gravity DHT22 module is designed to operate at a nominal 5V DC supply. It is compatible with the standard 5V logic levels found on Arduino Uno and similar boards. While the core DHT22 chip can operate from 3.3V to 5.5V, this specific module's circuitry is optimized for a stable 5V input.

Connect the module's VCC (red wire) to Arduino 5V, GND (black wire) to GND, and the Signal (green wire) to any digital I/O pin (e.g., pin 2). Use a library like 'DHT sensor library' from Adafruit. In your sketch, define the sensor type as DHT22 and the pin number, then call functions like `readTemperature()` and `readHumidity()` to get calibrated values.

Yes, the DHT22 uses a single digital data line to transmit a 40-bit data packet that contains both the temperature and humidity readings. Each query to the sensor returns a complete dataset for both parameters. The library handles the parsing, allowing you to read both values with separate function calls after a single measurement cycle.

The DHT22 offers significantly higher precision and a wider measurement range compared to the DHT11. The DHT22 measures from -40 to 80°C with ±0.5°C accuracy and 0-100% RH with ±2% accuracy. The DHT11 is limited to 0-50°C with ±2°C accuracy and 20-80% RH with ±5% accuracy. For applications requiring high precision or operation in extreme conditions, the DHT22 is the superior choice.