Adafruit SHT41 Trinkey - USB Temperature and Humidity Sensor with NIST-Traceable Sensirion SHT41, plus or minus 0.2 degree C and or minus 1.8 %RH Accuracy for Data Logging and Environmental Monitoring
The Adafruit SHT41 Trinkey is a plug-in USB environmental sensor built around the Sensirion SHT41 temperature and humidity IC, packaged in the Trinkey form factor that plugs directly into a standard USB-A port without a cable, adapter, or breadboard. The SHT41 is a mature, globally deployed Sensirion sensor IC qualified to JEDEC JESD47 reliability standards and carrying NIST traceability for both its temperature and humidity measurement outputs, placing it in a higher accuracy and qualification tier than the generic DHT11 and DHT22 sensors commonly used in hobby and educational builds. Temperature accuracy is rated at up to plus or minus 0.2 degrees C, and relative humidity accuracy at up to plus or minus 1.8 %RH across a full operating range of -40 to 125 degrees C and 0 to 100 %RH, including fully condensing environments where many lower-grade humidity sensors produce unreliable or out-of-specification readings.
The Trinkey format presents the SHT41 as a directly USB-connected sensor accessible from any host computer, microcontroller with USB host capability, or CircuitPython-compatible board, with no soldering, wiring, or power supply management required beyond the USB connection itself. The SHT41 communicates over I2C fast mode plus at address 0x44 with CRC checksum validation on all data transfers, reducing the risk of corrupted readings passing undetected into data logging and monitoring pipelines. An onboard variable-power heater enables condensation removal from the sensor surface for recovery after exposure to saturated humidity conditions, extending reliable operation in environments where periodic condensation is unavoidable. The average bare sensor current of 0.4uA at 1Hz measurement rate and an idle current of 80nA make the SHT41 exceptionally power-efficient for a sensor of this accuracy class, relevant in USB-powered builds where total system power draw is a design consideration.
Key Features
- Sensor IC: Sensirion SHT41, a globally deployed, JEDEC JESD47-qualified temperature and humidity sensor with NIST traceability
- Temperature Accuracy: Up to plus or minus 0.2 degrees C across the -40 to 125 degrees C operating range
- Humidity Accuracy: Up to plus or minus 1.8 %RH across the 0 to 100 %RH operating range, including condensing environments
- USB Trinkey Format: Plugs directly into a USB-A port without a cable, adapter, breadboard, or external power supply
- Supply Voltage: 3.3-5V breakout supply range compatible with 3.3V and 5V host systems via USB power rail
- I2C Fast Mode Plus: High-speed I2C fast mode plus communication at address 0x44 with CRC checksum validation on all data transfers
- Condensing Environment Rated: Fully functional in condensing humidity conditions where lower-grade sensors produce out-of-specification readings
- Variable-Power Heater: Onboard heater enables condensation removal from the sensor surface for recovery after saturation exposure
- NIST Traceability: Factory-calibrated sensor output with NIST-traceable measurement reference for both temperature and humidity channels
- JEDEC JESD47 Qualification: Sensor IC qualified to JEDEC JESD47 reliability standards for long-term deployment confidence
- Ultra-Low Power: 0.4uA average current at 1Hz measurement rate and 80nA idle current for power-efficient continuous monitoring
- Compact Form Factor: 31.8x11.8x4.5mm / 1.6g for minimal physical footprint in USB port-mounted sensor deployments
Applications
- USB-connected temperature and humidity data logging on Windows, macOS, and Linux host computers without additional hardware
- CircuitPython and MicroPython environmental monitoring builds require a calibrated, NIST-traceable humidity and temperature sensor
- Laboratory and research-grade environmental monitoring requiring JEDEC-qualified sensor IC with CRC-validated I2C data output
- Condensing and high-humidity environment monitoring, where standard DHT-series sensors produce unreliable readings
- HVAC, cleanroom, and climate-controlled space monitoring using a compact USB-mounted calibrated sensor
- IoT and embedded environmental sensing builds require sub-1uA sensor current consumption at a 1Hz measurement rate
