传感器重要参数：

供电电压：1.5V—3.6

湿度测量范围：0—100%RH

温度测量范围:-40℃—105℃

消耗功率:2.7uW

通信方式:I2C

湿度精度范围（10%RH to 95%RH）:HTU20D±3%RH HTU21D±2%RH

湿度迟滞：±1%RH

测量时间：50ms

年漂移量：-0.5%RH/year

响应时间：5 s

同时HTU20D、HTU21D可以和瑞士的SHT20、SHT21实现完全兼容，硬件管脚上可以实现Pin to Pin，无需修改电路板。软件程序方面也和瑞士的SHT20、SHT21相同，可以实现兼容替换，无需做出任何修改。有着很好的价格优势，极具性价比.

HTU20D、HTU21D超小体积的温湿度一体数字输出模块是一款性能优良的产品。同时，HTU20D和HTU21D在价格、性能、功耗等方面都有很大优势。

Description:The HTU20/21D 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 communications. If you’re hooking up multiple I2C devices on the same bus, you may want to disable these resistors