DHT21 AM2301 Temperature & Relative Humidity Sensor Module - (AD28820)

Description:

The DHT21 is a highly accurate digital temperature and relative humidity sensor in a rugged package. It integrates a capacitive humidity sensor, a thermistor, and a microcontroller responsible for performing the analog-to-digital conversion. Its more robust plastic packaging compared to the DHT11 and DHT22 sensors makes the DHT21 ideal for outdoor applications. It is used in automatic temperature control, air conditioning, environmental monitoring in agriculture, and more.

Integration is simple, both in terms of software and hardware. At the software level, Arduino libraries are available with support for the "Single Bus" protocol. As for the hardware, you only need to connect the red wire to the 3-5V power supply, the black wire to ground (0V), and the yellow wire to a digital pin on your Arduino. If you want to connect multiple sensors to the same Arduino, each sensor must have its own data pin. Perhaps the only disadvantage of this sensor is that it can only obtain new data every two seconds.

The DHT21 has improved features over the DHT11 sensor, such as better resolution, greater precision, and more robust packaging.

Technical specifications

- Operating Voltage: 3.5V - 5.5V DC

- Current consumption: 1mA - 1.5mA

- Sensing time: 2s

- Digital protocol: Single bus (1 cable)

- Temperature Range: -40 to 80°C

- Temperature Resolution: 0.1°C

- Temperature Accuracy: +- 0.5°C

- Relative Humidity Range: 0 to 100% RH

- Humidity Resolution: 0.1%RH

- HR Accuracy: +- 3%

- Model: AM2301

- Dimensions: 60*28*12mm

- Black plastic housing

- Cable length: 50cm

Cables

- Red: Power + (5 VDC)

- Black: Ground (0 VDC)

- Yellow: Digital data I/O

*We recommend using a 4.7K Ohm pull-up resistor between the data cable and 5V.

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Data sheet