Patent ID: 11881265
Assignee: KIOXIA CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 14:
15. A memory system data reading method for a non-volatile memory with memory cells for storing multiple bit data, the data reading method comprising:
applying read voltages to memory cells of a non-volatile memory at different threshold levels to read data written to the memory cells of the non-volatile memory;
storing first information indicating a first initial value for each different threshold level of the read voltages;
storing second information that identifies whether data was successfully read from a sub-group of the memory cells when the respective different threshold levels of the read voltages are set to the first initial values, and
storing third information that indicates a second initial value for each different threshold level of the read voltages for at least one sub-group for which a data reading was unsuccessful when a read voltage was set to the first initial value.