DHT22 Digital Temperature Humidity Sensor

DHT22 (AM2302) Digital Temperature & Humidity Sensor Module

The DHT22 Digital Temperature & Humidity Sensor Module, also known as AM2302, is a high-precision digital sensor designed to measure ambient temperature and relative humidity with improved accuracy compared to the DHT11. It is widely used in IoT applications, weather stations, smart home systems, and advanced Arduino-based projects.

The sensor integrates a capacitive humidity sensor, an NTC temperature sensor, and a high-performance digital signal processor, delivering calibrated and stable output through a single-wire digital interface.

Key Features

• Measures both temperature and humidity with high accuracy

• Fully digital signal output

• Factory-calibrated for reliable measurements

• Single-wire serial communication

• Better accuracy and wider range than DHT11

• Low power consumption

• Compact and durable design

Working Principle

The DHT22 measures humidity using a capacitive humidity sensing element and temperature using an NTC thermistor. An internal microcontroller processes the sensor data and sends it as a digital signal to the host microcontroller.

Each data packet includes:

• Humidity data

• Temperature data

• Checksum for error detection

This ensures accurate and stable readings even in noisy environments.

Pin Configuration

• VCC: Power supply (3.3V – 6V DC)

• DATA: Digital data output

• GND: Ground

Technical Specifications

• Operating Voltage: 3.3V – 6V DC

• Temperature Range: -40°C to +80°C

• Temperature Accuracy: ±0.5°C

• Humidity Range: 0% – 100% RH

• Humidity Accuracy: ±2–5% RH

• Resolution:

  • Temperature: 0.1°C

  • Humidity: 0.1% RH

• Sampling Rate: 0.5 Hz (one reading every 2 seconds)

• Output Type: Digital (Single-Wire Protocol)

Applications

• Weather stations

• Smart home automation

• IoT environmental monitoring

• HVAC systems

• Greenhouse and agricultural monitoring

• Arduino, ESP8266, ESP32, Raspberry Pi projects

Image & Design Specifications (As Provided)

• Clean white background

• All unnecessary objects and watermarks removed

• Brand logo placed at the top-left corner, scaled 3× smaller than the component

• Image Resolution: 800 × 800 pixels

• File Size: Approximately 80 KB

• Resolution: 96 DPI

• Color Depth: 24-bit