If there is no ongoing EEPROM write/erase operation, the NVMCTRL will enter sleep mode, when the system enters sleep mode.
If an EEPROM write/erase operation is ongoing when the system enters a sleep mode, the NVM block, the NVMCTRL and the peripheral clock will remain ON until the operation is finished and will be automatically turned off once the operation is completed. This is valid for all sleep modes, including Power-Down.
The EEPROM Ready interrupt will wake up the device only from Idle sleep mode.