DHT11 Temperature and Humidity Sensor Module – Digital Relative Humidity & Temperature Sensor for Arduino, ESP32, and Raspberry Pi

Product Description The DHT11 is an ultra-low-cost, highly reliable digital temperature and humidity sensor module designed for easy integration with microcontrollers. It features a calibrated digital signal output that carries both temperature and humidity data on a single wire. The sensor includes a resistive-type humidity measurement component and an NTC temperature measurement component, connected to a high-performance 8-bit microcontroller. This module is the most popular choice for beginners and hobbyists due to its simplicity, pre-calibrated output, and stability over time. It is perfectly suited for indoor weather stations, home automation projects, and basic environmental monitoring using Arduino, ESP32, or Raspberry Pi.

Key Features

• Calibrated Digital Signal: Every sensor is factory-calibrated with a high-precision humidity chamber, and calibration coefficients are stored in internal memory.

• Single-Bus Interface: Uses only one digital pin for bi-directional communication, simplifying wiring and reducing I/O requirements.

• Low Power Consumption: Operates efficiently with low current draw, making it suitable for standard battery-powered electronics.

• Integrated Processing: Includes an internal MCU that handles complex signal processing, providing a ready-to-use digital value.

• Excellent Stability: Features a high-quality protective housing that ensures long-term reliability in non-condensing environments.

Technical Details

• Sensing Elements: Utilizes a resistive humidity sensing component and a high-precision NTC thermistor for temperature detection.

• Protocol Type: Uses a proprietary single-wire serial protocol with a specific start signal and 40-bit data packet (Humidity + Temp + Checksum).

• Communication Speed: Features a relatively low data rate to ensure signal integrity over longer wire distances (up to 20 meters).

• Power Supply Range: Works seamlessly with a wide voltage range from 3.3V to 5.5V DC, covering all major logic levels.

• Data Resolution: Outputs integer values for temperature and humidity, providing sufficient precision for home and office environments.

• Refresh Rate: Designed for a 1-second sampling interval, which provides a balanced update frequency for environmental tracking.

• Internal Checksum: Each data transmission includes an 8-bit checksum to verify data integrity and prevent errors from electrical noise.

• Physical Housing: Enclosed in a perforated blue plastic casing that allows airflow to reach the internal sensors while preventing physical damage.

• PCB Integration: This module version includes an on-board 10k pull-up resistor and filter capacitor, making it "plug-and-play" with a 3-pin connector.

• Logic Compatibility: TTL digital output ensures direct compatibility with 5V Arduino boards and 3.3V ESP8266/ESP32 modules.

• Moisture Protection: Built-in moisture-resistant coating on the internal PCB protects sensitive components from oxidation in humid air.

• Operating Current: Draws approximately 0.5mA to 2.5mA during active measurement and drops to a micro-ampere level in standby.

• Signal Duration: The protocol relies on precisely timed pulses (micros); hence high-speed library polling is recommended for accurate reads.

• Standard Connectors: Features a 3-pin breakout (VCC, GND, Data) with 2.54mm pitch for easy jumper wire connections.

• Thermal Response: Typically stabilizes within 6 to 15 seconds after a significant change in environmental temperature.