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(Si7021) Temperature Humidity Sensor For Arduino

This humidity and temperature sensor is Discontinued Now, We recommend LM35 Temperature Sensor For Arduino as a suitable replacement.

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 RH/temperature sensors in 3x3 mm DFN-6 packages, featuring precision sensing over a wider range and lower power consumption. The optional factory-installed cover offers a low profile, convenient means of protecting the sensor during assembly (e.g., reflow soldering) and throughout the life of the product, excluding liquids (hydrophobic/oleophobic) and particulates. 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.


  • HVAC/R
  • Thermostats/humidistats
  • Indoor weather stations
  • Automotive climate control and defogging


  • Operating Voltage: 1.9 - 3.6V (recommend 3.3V)
  • Standby Current: 60nA
  • Temperature Range: -40 - 85°C (recommend -10 - 60°C)
  • Temperature Accuracy: ±0.4°C (-10 - 85°C)
  • Humidity Range: 0-100%RH (recommend 20% - 80%RH)
  • Humidity Accuracy: ±3%RH (0-80%RH)
  • Temperature Conversion Time: 7ms
  • Humidity Conversion Time: 17ms (RH measurement will automatically initiate a temperature measurement)
  • Interface: I2C, Gadgeteer and soldering pad with 2.5mm (0.10")spacing
  • Size: 32X32mm(1.26x1.26")
  • Mounting hole: inner diameter is 3.2mm(0.13"), spacing is 25mm(0.98")



  • Si7021 Temperature and Humidity Sensor x1
  • Gadgeteer IDC10 Cable x1

The (Si7021) Temperature Humidity Sensor For Arduino appears in the following collections: