Sensirion SHT40I-HD1F-R2 Humidity & Temperature Sensor - I2C Interface, NIST-Traceable

The SHT40I-HD1F-R2 operates from a wide supply voltage range of 2.3V to 5.5V DC. This makes it directly compatible with both 3.3V and 5V microcontroller systems like Arduino, Raspberry Pi, and ESP32 without requiring a level shifter.

Communication is via a standard I2C interface. The typical 4-pin connection includes VDD (power), GND (ground), SDA (data line), and SCL (clock line). You must use pull-up resistors on the SDA and SCL lines as per I2C protocol specifications for reliable communication.

Each SHT40I-HD1F-R2 unit is individually calibrated against reference standards in an ISO/IEC 17025 accredited laboratory, with the calibration chain traceable to the National Institute of Standards and Technology (NIST). This ensures high measurement confidence and is often required for industrial quality control and regulatory applications.

Yes, its industrial-grade design includes an operating temperature range of -40°C to 125°C and robust ESD protection. However, for prolonged outdoor use, it must be properly housed to protect the sensing element from direct water exposure, condensation, and contaminants, as the DFN package itself is not fully sealed.