2. Soldering the headers Before using your click board, make sure to solder 1x8 male headers to both left and right side of the board. Two 1x8 male headers are included with the board in the package. 1 HTU21D click 2 3 4. Essential features Since it requires no calibration and uses only 2 1. Introduction communication lines, HTU21D click is great for quickly developing reliable environmental sensing nodes. Either for data logging (as in a weather station), or for humidity and temp. control in a HVAC system. The default resolution of the signal is set to 12-bit for Turn the board upside down so that Turn the board upward again. Make sure relative humidity and 14-bit for temperature the bottom side is facing you upwards. to align the headers so that they are readings (you can change the resolution in Place shorter pins of the header into the perpendicular to the board, then solder the range of 8-12 bits for humidity, and 12- appropriate soldering pads. the pins carefully. 14 bits for temperature.) HTU21D click carries a high-precision, easy-to-use relative humidity sensor 3. Plugging the board in with temperature output. The sensor is click plug and play, requiring no calibration to Once you have soldered the headers your use. The measurement range of HTU21D board is ready to be placed into the desired BOARD click is from 0 to 100 percents of relative mikroBUS socket. Make sure to align the www.mikroe.com humidity, and -40 to +125 degrees of cut in the lower-right part of the board with Celsius. The board communicates with the markings on the silkscreen at the the target microcontroller through mikroBUS socket. If all the pins HTU21D click manual v100 mikroBUS I2C lines: SCL and SDA (data). are aligned correctly, push the It uses a 3.3V power supply only. board all the way into the socket. 0 100000 027271 5. HTU21D click board schematic 6. Tip on sensor placement Relative humidity de- pends on temperature. To get the most acc- urate measurements from HTU21D click , its important to keep the sensor at the same temperature as the environment in which you want to measure the humidity. VCC-3.3 VCC-3.3 VCC-3.3 7. Code examples VCC-3.3 VCC-3.3 R1 Once you have done all the necessary R2 R3 2K2 U1 10K 10K AN PWM preparations, its time to get your click board 4 3 RST INT NC NC C1 up and running. We have provided examples LD1 CS TX 100nF 5 2 for mikroC , mikroBasic and mikroPascal SCK RX VDD GND SCK compilers on our Libstock website. Just SCL MISO DATA SCK 6 1 DATA SDA SCK SDA download them and you are ready to start. MOSI +3.3V +5V HTU21D GND GND MIKROBUS DEVICE CONNcom 8. Support MikroElektronika oers ff free tech support (www.mikroe.com/support) until the end of the products lifetime, so if something goes wrong, were ready and willing to help MikroElektronika assumes no responsibility or liability for any errors or inaccuracies that may appear in the present document. Specification and information contained in the present schematic are subject to change at any time without notice. Copyright 2014 MikroElektronika. All rights reserved.