Adafruit HDC3022 Precision Temperature & Humidity Sensor

This Adafruit HDC3022 Precision Temperature & Humidity Sensor breakout features the highest accuracy & precision one we've see so far! It has the TI HDC302x series chip with typical 0.5% accuracy for the RH sensor (with 0.19% long-term drift) and ±0.1°C typical accuracy for the temperature sensor.

This sensor has a true I2C interface for easy interfacing with only two wires (plus power and ground!). That makes it preferable to the janky DHT11/DHT22 sensors. The sensor is 5V safe, so you can use 1.8V to 5V power and logic levels without the need for shifters, so you can power and communicate with it using any microcontroller or microcomputer. With 4 selectable I2C addresses, you can have multiple sensors on one bus - unlike many other fixed-address T/RH sensors.

Adafruit have written a full-featured Arduino and CircuitPython/Python library, so whether you have an 8-bit microcontroller or a quad-core Raspberry Pi, you will be able to quickly get data from the sensor for your environmental monitoring needs. The library can setup the sensor rate/power, heater, alerts, offsets, and read data or NIST tracking ID.

If you prefer working on a breadboard, each order comes with one fully assembled and tested PCB breakout and a small piece of header. You'll need to solder the header onto the PCB, but it's fairly easy and takes only a few minutes even for a beginner. 

Please note: this sensor comes with a protective polyamide sticker on top, please remove before usage!

Specifications

• Relative humidity (RH) sensor:
  – Operating range: 0% to 100%
  – Accuracy: ±0.5% typical
  – Offset Error Correction: reduces offset to return device to within accuracy specification
  – Long-term drift: 0.19%RH/yr
  – Condensation protection with integrated heater
•  Temperature sensor:
  – Operating range: –40°C to 125°C
  – Accuracy: ±0.1°C typical
• NIST traceability: relative humidity & temperature
• Low power: average current 0.4 µA (sensor only, not including on-board green LED which can be disabled)
• I2C interface compatibility up to 1-MHz speeds
  – Four selectable I2C addresses
  – Data protection through CRC checksum
• Supply voltage: 1.62 V to 5.50 V
• Available auto measurement mode
• Programmable interrupts
• Programmable RH and Temp measurement offset