JAJSMG0C june 2021 – december 2022 HDC3020 , HDC3021 , HDC3022
PRODUCTION DATA
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 if the user wants to change the offset because the device could give unpredictable results if the device is in Auto Measurement Mode. Note the RH measurement uses the measured temperature for correction and does not use the programmed temperature offset, which allows the user to program a temperature offset to account for local heating without affecting RH accuracy.
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 for the time needed to complete programming a single location, tPROG, and the current required during programming, IEEPROM.