ZHCSIF4C June 2018 – April 2021 TMP117
To prevent accidental programming, the EEPROM is locked by default. When locked, any I2C writes to the register map locations are performed only on the volatile registers and not on the EEPROM.
Figure 7-7 shows a flow chart describing the EEPROM programming sequence. To program the EEPROM, first unlock the EEPROM by setting the EUN bit in the EEPROM unlock register. After the EEPROM is unlocked, any subsequent I2C writes to the register map locations program a corresponding non-volatile memory location in the EEPROM. Programming a single location typically takes 7 ms to complete and consumes 230 µA. Do not perform any I2C writes until programming is complete. During programming, the EEPROM_busy flag is set. Read this flag to monitor if the programming is complete. After programming the desired data, issue a general-call reset command to trigger a software reset. The programmed data from the EEPROM are then loaded to the corresponding register map locations as part of the reset sequence. This command also clears the EUN bit and automatically locks the EEPROM to prevent any further accidental programming. Avoid using the device to perform temperature conversions when the EEPROM is unlocked.