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7Semi SHT45 Digital Humidity and Temperature Sensor Breakout With I2C Interface and Qwiic Connector for Easy MCU Integration
The 7Semi SHT45 is a digital relative-humidity and temperature sensor breakout for projects that need dependable environmental data. It measures humidity with +/-1.0 %RH accuracy and temperature with +/-0.1 deg C accuracy. The I2C interface offers preconfigured addressing, with the default address at 0x44, so it connects easily to Arduino, ESP32, Raspberry Pi and other 3.3V microcontroller boards. The Qwiic connector allows quick, solder-free hookup.
The board is built for low-power and long-running designs. It draws an average current of 0.4 uA at a 1 Hz measurement rate and only 80 nA when idle, which suits battery-powered sensor nodes. A built-in variable-power heater with three heating levels helps the sensor work in demanding environments. The sensor stays fully functional in condensing conditions and offers NIST traceability for measurement confidence. It is well-suited to weather stations, HVAC monitoring, data loggers and IoT devices.
Key Features
- High Humidity Accuracy: +/-1.0 %RH relative-humidity accuracy for consistent readings.
- Precise Temperature Sensing: +/-0.1 deg C accuracy across the full operating range.
- Wide Operating Range: 0 to 100 %RH and -40 to 125 deg C.
- Ultra-Low Power Consumption: 0.4 uA average current at 1 Hz and 80 nA idle current.
- Digital I2C Interface: Default address 0x44, with preconfigured I2C address options.
- Qwiic Connector: Plug-and-play connection with no soldering needed for compatible boards.
- Variable Power Heater: 3 heating levels for operation in demanding conditions.
- Condensation Tolerance: Fully functional in condensing environments.
- NIST Traceability: Supports measurement reliability and calibration confidence.
- 3.3V Supply: Works directly with common 3.3V logic boards.
Applications
- Weather stations and outdoor environmental monitoring
- HVAC and building-automation systems
- Battery-powered IoT sensor nodes
- Data loggers and cold-chain monitoring
- Greenhouses, agriculture and grow-room control
- Smart-home humidity and comfort monitoring
- Industrial process and equipment monitoring
- Education, prototyping and development projects
