Temp&Hum 12 Click is a smart environmental temperature and humidity sensor Click board™, packed with features which allow easy and simple integration into any design that requires accurate and reliable humidity and temperature measurements. The capacitive-based sensor includes new integrated digital features and a heating element to dissipate condensation and moisture. This translates to a prolonged life of the Click board™ itself.

Temp&Hum 12 Click is a perfect solution for a wide range of applications that depend on accurate temperature and humidity readings. With its low power consumption and programmable interrupt requests capability, it is also a perfect choice for various temperature and relative humidity based IoT applications, smart thermostats and smart home assistants.

The sensor IC used on the Temp&Hum 12 Click is the HDC2080, a Low Power Humidity and Temperature Digital Sensor from Texas Instruments. This sensor is factory calibrated to 2% relative humidity and 0.2°C temperature accuracy. It has an integrated heating element that is used to evaporate condensation, protecting the sensor that way. This heating element can be simply activated by setting a bit in the appropriate register. In the case when the heater is powered on, the typical current consumption is about 90mA.

Internally, two sensors are connected to the two separated ADC sections, which can be set to sample measurements with the resolution of 9, 11 or 14 bits, based on the measurement time. The OTP memory holds the calibration coefficients that are applied to the measured value and the results are stored on the output registers, in the MSB/LSB format. These values are then used in formulas found in the HDC2080 datasheet so that the final temperature or relative humidity data can be calculated. It is also possible to correct the offsets with custom values.

HDC2080 IC uses the I2C protocol to communicate with the host MCU. Its I2C bus pins are routed to the mikroBUS™ I2C pins and are pulled to a HIGH logic level by the onboard resistors. The final I2C address of this IC is already determined by setting ADDR pin to GND (LOW logic level for 0).

Temp&Hum 12 Click supports programable temperature and humidity thresholds in the HDC2080 allow the device to send a hardware interrupt to wake up the microcontroller when necessary. In addition, the power consumption of the HDC2080 is significantly reduced, which helps to minimize self-heating and improve measurement accuracy. More information about these registers can be found in the HDC2080 datasheet.

HDC2080 IC itself is a very low power consumption device and it can work in two modes: sleep and active (measurement) mode. The device enters the sleep the mode as soon as possible, to save power. This makes the HDC2080 suitable to be used in battery-powered applications. In these applications, the HDC2080 spends most of the time in sleep mode, with the typical current consumption of 50 nA. While in the active mode, measurement can be configured either to automatic (with the predefined output data rate) or on-demand. In the automatic mode, the measurement is triggered in predefined time intervals, while on-demand measurement happens whenever the I2C command is sent. As soon as the single measurement is finished, the device falls back to the sleep mode.

The provided Click board™ library contains simple and easy to use functions, which simplify configuring and reading of the measurement data. These functions are demonstrated in the included example application and can be used as a reference for custom projects. These functions can be used in mikroC, mikroBasic and mikroPascal compilers for all MCU architectures, supported by MikroElektronika.

• Interface: I²C
• Compatibility: mikroBUS™
• Dimensions: 42.9 x 25.4mm
• Input Voltage: 3.3V
• Temperature Accuracy: Typ. +/-0.2°C, Max. +/-0.4°C
• Humidity Accuracy: Typ. +/-2%RH, Max. +/-3%RH
• Operating temperature: Min. -40°C, Max. 85°C
• Relative Humidity Operating Range: Min. 0%RH, Max. 100%RH
• I2C clock frequency: Min. 10kHz, Max. 400kHz

• Schematic
• HDC2080 Datasheet
• mikroSDK
• GitHub