BlueDot HDC1080 Low Power Humidity Sensor
The HDC1080DMBR is a high-accuracy humidity and temperature sensor from Texas Instruments with a very low power consumption, making the device ideal for battery-powered applications. The HDC1080 also includes voltage supply monitoring and an integrated heater.
Here are the board’s main features:
- High Accuracy. Measurement accuracy of up to ±2% across the range of 20°C and 60°C. The HDC1080 also provides a 14-bit temperature sensor with a measurement accuracy of typically ±0.2°C between 5°C and 60°C.
- Wide Range Supply Voltage. The sensor operates from 2.7 V and 5.5 V at VCC, dispensing the need for voltage regulation.
- Voltage Supply Monitoring. The sensor indicates when the supply voltage is less than 2.8 V, which is useful for battery-powered applications.
- Low Power Consumption. It has a very low power consumption, up to 1.3 µA, which minimizes the impact of self-heating.
- I²C Communication. The sensor communicates through the I²C protocol using 0x40 as the address.
Connecting via I²C
Connecting the HDC1080 to the I²C bus is very easy. The first step is to connect the board to the power supply.
- VCC Pin. Connect the VCC pin from the board to either 5V or 3.3V output from your Arduino.
- GND Pin. Connect the GND pin from the board to the GND from the Arduino.
Great! Now we need to connect the sensor to the I²C bus. The I²C communication uses two wires. The clock signal is generated by the Arduino and transferred to the sensor through the SCL line. The Arduino can send commands to the sensor using the SDA line. Just as well, all data from the sensor goes back to the Arduino through the SDA line. Because of that, the SDA line is bidirectional.
- SDA Pin. Connect the SDA pin from the board to the SDA line on the Arduino. This corresponds to the pin A4 on the Arduino Uno.
- SCL Pin. Connect the SCL pin from the board to the SCL line on your Arduino. This corresponds to the pin A5 on the Arduino Uno.
Installing Arduino Library
Although there is currently no Arduino Library from BlueDot available for this sensor, you can use the library for the ClosedCube to connect to the HDC1080. You can download and install the library directly from the Arduino IDE. Just open the Arduino IDE and go to Sketch > Include Library > Manage Libraries… and search for the HDC1080 on the Library Manager. You can find this library under the name ClosedCube HDC1080.
After installing the library we can open an example sketch. Just go to File > Examples > ClosedCube HDC1080 and open the sketch hdc1080demo.
No changes to the sketch are needed. Just upload the sketch to your microcontroller and you will see the first measurements on the serial monitor.
A 3D model of the BlueDot HDC1080 board is available as a STEP file (click here to download). A STEP file is a CAD file format widely used for exchanging CAD files between companies and can be easily read by most (if not all) CAD software applications.
You can also view 3D models online without installing any software on your computer. The images below were taken using Autodesk Viewer, an online, free-to-use tool from Autodesk. It does require registration at Autodesk, but it is worth it!