Description:The HTU21D is a low-cost, easy to use, highly accurate,  digital humidity and temperature sensor. This sensor is ideal for environmental sensing and data logging and perfect for a weather stations or humidor control systems. All you need is two lines for I2C communication and you'll have relative  humidity readings and very accurate temperature readings as a bonus!

There are only four pins that need to be hooked up in order to start using this sensor in a project. One for VCC,  one for GND,  and two data lines for I2C communication. This breakout board has built in 4.7k pull up resistors for I2C. And two data lines for I2C communication. This breakout board has built in 4.7k pull up resistors for I2C communications. If you're hooking up multiple I2C devices on the same bus, you may want to disable these resistors

Built from Humirel's high-performance humidity-sensing components, the new HTU21D temperature and humidity sensor sets a new standard in size and intelligence: it comes in a reflow friendly dual flat pin free DFN package with a 3x3mm underside and a height of 1.1mm. Sensor output calibrated digital signal, standard I2C format. Diversified output mode, wide operating voltage range, and high temperature accuracy and humidity accuracy. HTU21 series modules are designed for low power consumption and small volume applications, with good quality, fast response speed, strong anti-interference ability, high cost performance, tiny volume (3x3mm), very low power consumption

Important parameters of sensor:

Power supply voltage: 1.5V - 3.6

Humidity measurement range: 0-RH

Temperature measurement range :-40℃ -- 105℃

Power consumption :2.7uW

Communication mode :I2C

Humidity accuracy range (10%RH to 95%RH) :HTU21D±2%RH

Humidity lag: ±1%RH

Measurement time: 50ms

Annual drift: -0.5%RH/year

Response time: 5 s

At the same time, HTU21D can be fully compatible with Swiss SHT20 and SHT21, and the hardware pins can be Pin to Pin without modifying the circuit board. Software program and Swiss SHT20, SHT21 same, can achieve compatible replacement, without any modification. At the same time, compared with Swiss SHT20 and SHT21, HTU21D has a good price advantage, cost-effective.

The HTU21D ultra-small volume integrated temperature and humidity digital output module is a product of excellent performance by Humirel, a French sensor manufacturer. At the same time, HTU21D has great advantages in price, performance, power consumption and other aspects.

Pin arrangement distribution