The Si7021 I2C Humidity and Temperature Sensor is a monolithic CMOS IC integrating humidity and temperature sensor elements, an analog-to-digital converter, signal processing, calibration data, and an I2C Interface. The patented use of industry-standard, low-K polymeric dielectrics for sensing humidity enables the construction of low-power, monolithic CMOS Sensor ICs with low drift and hysteresis, and excellent long term stability. The humidity and temperature sensors are factory-calibrated and the calibration data is stored in the on-chip non-volatile memory. This ensures that the sensors are fully interchangeable, with no recalibration or software changes required. The Si7021 is available in a 3x3 mm DFN package and is reflow solderable. It can be used as a hardware- and software-compatible drop-in upgrade for existing Featuring precision sensing over a wider range and lower power consumption. The Si7021 offers an accurate, low-power, factory-calibrated digital solution ideal for measuring humidity, dew-point, and temperature, in applications ranging from HVAC/R and asset tracking to industrial and consumer platforms.
Power supply : 3-5V Relative humidity: ± 3% RH (max), 0-80% RH Temperature: ±0.4°C (max), -10 to 85°C Operating range: 0 to 100% RH Operating range: Up to -40°C to +125 °C Wide operating voltage: 1.9V - 3.6V Low power consumption: 150 ?A active current Standby current: 60 nA Size: 1.3*1cm/0.51*0.39"
HVAC/R Thermostats/humidistats Respiratory therapy White goods Indoor weather stations Micro-environments/data centers Automotive climate control and defogging Asset and goods tracking Mobile phones and tablets
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 for humidity 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!