The DHT22 Digital Temperature and Humidity Sensor Module (also known as the AM2302) is an ultra-reliable, high-performance climate sensing module designed for microcontrollers and IoT applications. While the entry-level DHT11 sensor is adequate for basic tasks, the DHT22 offers significantly higher resolution, wider measuring ranges, and superior accuracy across both temperature and relative humidity parameters.

The module features a high-performance 8-bit microcontroller inside that processes signals from a polymer capacitive humidity element and an NTC temperature sensing element. It outputs a pre-calibrated 40-bit digital signal over a single-bus digital interface. The module comes mounted on a compact breakout PCB featuring an onboard pull-up resistor and power indicator, enabling direct plug-and-play operation without external circuit components.

Technical Specifications

Pinout Description

• VCC: 3.3V – 5.5V Power Supply input.

• DATA / OUT: Digital signal output pin (Connects to microcontroller GPIO).

• GND: Ground connection.

Basic Arduino Connection & Example Code

Wiring

• VCC ➔ Arduino 5V (or 3.3V)

• GND ➔ Arduino GND

• DATA ➔ Arduino Digital Pin 2

// Requires the "DHT sensor library" by Adafruit
#include <DHT.h>

#define DHTPIN 2       // Digital pin connected to the DHT22
#define DHTTYPE DHT22  // DHT 22 (AM2302)

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  Serial.println(F("DHT22 Climate Sensor Test"));
  dht.begin();
}

void loop() {
  // Wait 2 seconds between measurements (DHT22 sampling rate)
  delay(2000);

  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature(); // Celsius

  if (isnan(humidity) || isnan(temperature)) {
    Serial.println(F("Failed to read from DHT22 sensor!"));
    return;
  }

  Serial.print(F("Humidity: "));
  Serial.print(humidity);
  Serial.print(F("%  |  Temperature: "));
  Serial.print(temperature);
  Serial.println(F("°C"));
}

Key Features & Highlights

• High Precision & Wide Range: Outperforms standard DHT11 modules in both measurement range (-40°C to 80°C) and precision.

• Pre-Calibrated Digital Output: Factory-calibrated inside an accurate calibration chamber; calibration coefficients are stored in internal OTP memory.

• Integrated Breakout PCB: Includes onboard pull-up resistors for immediate breadboard connection and stable single-bus communication.

• 3.3V & 5V Logic Compatible: Natively works with 3.3V boards (ESP8266, ESP32, Raspberry Pi Pico) and 5V boards (Arduino Uno, Mega, Nano).

• Long Distance Transmission: Signal transmission distance can reach up to 20 meters with proper cable shielding.

Common Applications

• Environmental monitoring nodes, weather stations, and HVAC climate control.

• Smart home automation, dehumidifier triggers, and incubator controls.

• Cold-chain warehouse storage monitoring and greenhouse automation.

• Educational STEM projects, robotics environmental sensing, and IoT logging.

What’s Included in the Box

• 1 × DHT22 (AM2302) Digital Temperature and Humidity Sensor Breakout Module

• 1 × 3-Pin Female-to-Female Jumper Cable Wire

Why Buy From Aryabot?

• 100% Quality Assured: Pre-tested modules verified for stable digital communication and accurate thermal-hygrometric responses.

• GST Invoice Provided: Tax-compliant B2B invoices generated for commercial deployments, research institutions, and corporate projects.

• Pan-India Express Shipping: Fast processing and reliable delivery direct from our Noida distribution warehouse.