SHT4xI-Digital th 4 Generation, High-Accuracy, 16-bit, Industrial-Grade, Relative Humidity and Temperature Sensor Features Relative humidity accuracy: up to 2 %RH Fully functional in condensing environment Temperature accuracy: up to 0.2 C Variable power heater Supply voltage: 2.3 V 5.5 V NIST traceability Average current: 21 A (at meas. rate 1 Hz) Mature technology from global market leader I2C fast mode plus, CRC checksum JEDEC JESD47 qualification, high ESD protec. Operating range: 0100 %RH, -40125 C Patented protection options General Description SHT4xI-Digital is an industrial-grade digital sensor platform for measuring relative humidity and temperature with different accuracy classes. It meets demanding ESD and robustness requirements of industrial applications. The sensors can be interfaced via several preconfigured I2C addresses. An integrated heater allows for advanced on-board-diagnostics while the sensor element is designed for harsh conditions such as condensing environments. The four-pin dual- flat-no-leads package is suitable for surface mount technology (SMT) processing. Patented protection options such as ePTFE membranes and polyimide foils can be pre-ordered. Device Overview Functional Block Diagram Products Details SHT40I-AD1B base RH&T accur., 0x44 I2C addr. SHT41I-AD1B improved RH&T accur. 0x44 I2C addr. Full product list on page 14 www.sensirion.com / D1 Version 1 November 2021 1/15 Contents Features ........................................................................................................................................................................ 1 General Description ................................................................................................................................................... 1 Device Overview ......................................................................................................................................................... 1 Functional Block Diagram ........................................................................................................................................ 1 1 Quick Start Hello World ..................................................................................................................................... 3 2 Humidity and Temperature Sensor Specifications ......................................................................................................... 4 2.1 Relative Humidity ............................................................................................................................................ 4 2.2 Temperature ..................................................................................................................................................... 5 2.3 Recommended Operating Conditions ...................................................................................................... 5 3 Electrical Specifications ........................................................................................................................................ 6 3.1 Electrical Characteristics .............................................................................................................................. 6 3.2 Timings ............................................................................................................................................................... 7 3.3 Absolute Maximum Ratings ......................................................................................................................... 7 4 Sensor Operation .................................................................................................................................................... 7 4.1 I2C communication ......................................................................................................................................... 7 4.2 I2C Communication Timing ......................................................................................................................... 8 4.3 Data type & length .......................................................................................................................................... 8 4.4 Checksum Calculation ................................................................................................................................... 8 4.5 Command Overview ...................................................................................................................................... 9 4.6 Conversion of Signal Output ....................................................................................................................... 9 4.7 Serial number ................................................................................................................................................. 10 4.8 Reset ................................................................................................................................................................. 10 4.9 Heater Operation........................................................................................................................................... 10 5 Physical Specification .......................................................................................................................................... 10 5.1 Package Description .................................................................................................................................... 11 5.2 Package Outline ............................................................................................................................................ 11 5.3 Land Pattern ................................................................................................................................................... 11 5.4 Pin Assignment & Laser Marking ............................................................................................................. 12 5.5 Thermal Information ..................................................................................................................................... 13 6 Quality and Material Contents........................................................................................................................... 13 7 Tape and Reel Packaging .................................................................................................................................. 13 8 Product Name Nomenclature ............................................................................................................................ 14 9 Ordering Information ............................................................................................................................................ 14 10 Bibliography .......................................................................................................................................................... 14 11 Revision History .................................................................................................................................................. 14 www.sensirion.com / D1 Version 1 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