Resources

SHT40 Datasheet
Arduino Library

7Semi SHT40 Digital Humidity and Temperature Sensor Probe with I2C Interface and 1-Meter Cable
The 7Semi SHT40 Digital Humidity and Temperature Sensor Probe delivers accurate and repeatable environmental readings using a capacitive polymer sensing element with 16-bit resolution. It measures temperature with an accuracy of +/- 0.2 deg C and relative humidity with an accuracy of +/- 1.8 %RH, covering a temperature range of -40 deg C to +125 deg C and a humidity range of 0 to 100 %RH. The sensor operates on an ultra-low average current of 0.4 uA, making it well-suited for battery-powered and always-on monitoring applications. A built-in heater helps maintain sensing stability in high-humidity conditions, while CRC-based data protection ensures reliable digital communication.
The probe uses a four-wire I2C interface (address 0x44) for straightforward connection to microcontrollers and development boards, and the 1-meter cable allows the sensor element to be positioned away from the main control enclosure for remote or hard-to-reach sensing points. Housed in a ventilated stainless-steel probe body, the sensor is protected from dust and physical contact while remaining fully exposed to surrounding air for accurate readings. It is commonly used in HVAC systems, greenhouses, weather stations, cold-storage units, and indoor climate-monitoring setups. For best long-term accuracy, the sensor should be operated within the recommended range of 5 deg C to 60 deg C and 20 to 80 %RH, as prolonged exposure outside this range, particularly at high humidity, may cause a temporary offset in the humidity signal.
Key Features

High Accuracy: +/- 1.8 %RH and +/- 0.2 deg C for dependable readings.
Wide Measurement Range: 0 to 100 %RH and -40 deg C to +125 deg C.
Low Power Consumption: Ultra-low average current of 0.4 uA.
Fast Digital Interface: I2C communication with CRC-based data protection.
Integrated Heater: Maintains reliable operation in high-humidity environments.
Protective Probe Housing: Ventilated metal enclosure allows accurate air exposure while shielding the sensor.
Remote Sensing Cable: 1-meter extended cable enables placement away from the main controller.
Easy Connectivity: Four-wire I2C interface compatible with common microcontrollers and development boards.

Customisation: Length of the wire, length of stainless steel probe and thickness of the steel probe can be customised for quantity orders. Contact [email protected] for more details.
Applications

HVAC and building climate-control systems
Greenhouse and agricultural environment monitoring
Weather stations and outdoor environmental logging
Indoor air-quality and climate monitoring
Cold-storage and warehouse humidity tracking
Industrial process monitoring requiring remote sensing points