DHT21 Capacitive Digital Temperature and Humidity Sensor

The DHT21 is Capacitive Digital Temperature and Humidity Sensor which is a low-cost, easy-to-use sensor that can use to measure the temperature and humidity of the surrounding environment. DHT21 is a digital sensor that outputs its readings in a digital format, which makes it easy to interface with microcontrollers.

The DHT21 sensor has a 3-pin interface that consists of a power pin, a ground pin, and a data pin. The data pin used to transmit the sensor’s readings in a digital format.

The DHT21 sensor can measure temperature in a range of -40°C to 80°C with an accuracy of ±1°C. The humidity range is from 0% to 100% with an accuracy of ±2%. The sensor also has a minimum sampling time of 2 seconds, which means that the sensor cannot be polled more often than every 2 seconds.
A capacitive digital temperature and humidity sensor is a type of sensor that uses a capacitive sensor to measure the temperature and humidity of the surrounding environment. The capacitive sensor is a small, thin film that is sensitive to changes in humidity. When the humidity changes, the capacitance of the sensor changes. The sensor’s readings are then convert into digital signals that can read by a microcontroller.

The DHT21 sensor can be powered by a voltage in the range of 3.3V to 5V. The typical operating voltage is 5V. The sensor has a low power consumption of 2.5mA.

Features : –

The DHT21 is a high-performance temperature and humidity sensor that offers a number of advantages over other sensors on the market.DHT21 is a high performance temperature and humidity sensor, providing accurate measurement, low power consumption, long distance data transmission, automatic calibration and long life.

Accurate measurement: The DHT21 is accurate to within ±1°C for temperature and ±2% for humidity. This means that the sensor’s readings are within 1°C of the actual temperature and within 2% of the actual humidity.
Low power consumption: The DHT21 has a low power consumption of 2.5mA, making it suitable for battery-powered applications.
Long distance data transmission: The DHT21 can transmit data over a long distance, making it suitable for applications where the sensor is located far away from the microcontroller.
Automatic calibration: The DHT21 automatically calibrates itself, which means that the sensor’s readings are accurate over time.
Long life: The DHT21 has a long life of up to 10 years, making it a reliable sensor for long-term applications.

DHT21 Capacitive Digital Temperature and Humidity Sensor Specifications : –

The DHT21 sensor is accurate to within ±1°C for temperature and ±2% for humidity. This means that the sensor’s readings are within 1°C of the actual temperature and within 2% of the actual humidity. Here are some of the specifications of the DHT21 sensor:

Operating voltage: 3.3V to 5V
Operating current: 2.5mA
Input signal: Digital signal via 1-wire bus
Sensing element: Polymer capacitive sensor
Operating range: Humidity: 0-100%RH; Temperature: -40~80Celsius
Accuracy: Humidity: +-2%RH(Max +-5%RH); Temperature <+-0.5Celsius
Response time: 2 seconds
Dimensions: 15.3mm (0.6″) length x 7.8mm (0.3″) width x 25.3mm (1.0″) height
Weight: 2.4g (0.08oz)

DHT21 Capacitive Digital Temperature and Humidity Sensor Applications : –

The DHT21 is a versatile sensor that can use in a wide range of electronic projects. If you are looking for a sensor to measure temperature and humidity, the DHT21 is a good option to consider. The DHT21 is a popular sensor for a variety of applications, including:

Home automation: The DHT21 sensor can use to control home automation devices, such as thermostats and humidifiers, based on the temperature and humidity in the home.
Weather monitoring: The DHT21 sensor can use to create a portable weather station that can be used to measure the temperature and humidity in different locations.
Environmental monitoring: The DHT21 sensor can use to monitor the environment, such as the humidity and temperature of the soil.
Industrial control: The DHT21 sensor can use to control industrial processes, such as the temperature of a manufacturing plant.
Medical devices: The DHT21 sensor can use in medical devices to monitor the temperature and humidity of the patient’s environment.
Agriculture: The DHT21 sensor can use in agriculture to monitor the temperature and humidity of the soil and air, which can help to optimize crop yields.