The HDC302x can be programmed to return a relative humidity measurement and/or a temperature measurement that accounts for a programmed offset value. An operation bit determines whether to add or subtract the offset from the actual sensor measurement results. This feature is targeted for designs where local heat sources can not be isolated from the temperature sensor and said heat sources show variation over time (due to different components being enabled/disabled). The command is documented in the Table 8-3. The device should be in shutdown mode when changing the offset because if it is in Auto Measurement mode. it could give unpredictable results.
Programming either offset value requires programming of a corresponding non-volatile memory location in the EEPROM. Therefore, I2C writes are not permitted until offset programming is complete. Refer to the electrical characteristics table tOS_PROG parameters for the time to complete a programming a single location. The HDC302x will draw approximately 230 µA during offset programming.