DHT 22 Temperature and Humidity Sensor

DHT22 Sensor Overview

The DHT22 sensor, also known as the AM2302, is a versatile digital temperature and humidity sensor known for its accuracy and reliability in various applications. Here’s an overview:

1. Type: Digital Temperature and Humidity Sensor.
2. Functionality:
   • Temperature Measurement: Measures ambient temperature with high accuracy.
   • Humidity Measurement: Measures relative humidity in the surrounding environment.
   • Digital Signal Output: Provides digital signals (via a single-wire serial interface) for both temperature and humidity readings.
3. Specifications:
   • Temperature Range: -40?C to 80?C (-40?F to 176?F).
   • Temperature Accuracy: ?0.5?C.
   • Humidity Range: 0% to 100% RH.
   • Humidity Accuracy: ?2% RH.
   • Operating Voltage: 3.3V to 5.5V DC.
   • Current Consumption: 2.5mA max during conversion.
   • Output: Digital signal (single-wire serial interface, similar to One-Wire protocol).
4. Features:
   • High Accuracy: Provides precise temperature and humidity readings.
   • Fast Response Time: Responds quickly to changes in environmental conditions.
   • Low Power Consumption: Suitable for battery-powered applications.
   • Stable Performance: Reliable performance across varying environmental conditions.

Typical Uses:

• Environmental Monitoring: Used in weather stations and environmental monitoring systems.
• HVAC Systems: Integrated into heating, ventilation, and air conditioning systems for climate control.
• Indoor Comfort: Monitors indoor temperature and humidity levels for comfort and health.
• Data Logging: Logs temperature and humidity data for analysis and visualization.

Key Benefits:

• Integrated Sensor: Combines temperature and humidity sensing in a single device.
• Easy Integration: Simple to interface with microcontrollers and single-board computers like Arduino and Raspberry Pi.
• Cost-Effective: Provides accurate measurements at a relatively low cost.

How to Use:

• Wiring: Connect the sensor’s Vcc pin to a power supply (3.3V or 5V), GND to ground, and the data pin to a digital input/output pin of your microcontroller.
• Data Retrieval: Use a library compatible with your microcontroller to read temperature and humidity values via the digital signal output.
• Calibration: Optionally calibrate the sensor based on environmental conditions for increased accuracy.