Patent ID: 7987314

Claim:
A non-volatile memory device which writes and reads data to and from said non-volatile memory based on a logical address given from an external device comprising: a non-volatile memory; and a controller, wherein said non-volatile memory includes a plurality of physical blocks, each of said plurality of physical blocks includes a plurality of partial physical blocks, each of said plurality of partial physical blocks includes a plurality of physical pages, and each of said plurality of physical pages has data regions and management regions, the logical address given from the external device includes a logical group address, a logical block address belonging to each logical group, and a page address belonging to each logical block, a data size of a logical group corresponds to that of said plurality of physical blocks, and a data size of a logical block corresponds to that of said plurality of partial physical blocks, said controller includes: an address conversion table having: an address conversion region for storing a relationship between said logical group address of the logical address given from the external device is converted to a physical block address in which a logical block belonging to the logical group is recorded; and an overlapped address registration region showing said physical block address in which data is overlapped when data of a certain logical group is recorded in said plurality of physical blocks; and an entry table showing whether each physical block is already written or erased, and when data to be written and the logical address of the data are given from the external device, the data and management information are written to an unwritten region of said plurality of partial physical blocks, the management information showing addresses of said plurality of partial physical blocks in which data included in the given logical address is written, and said address conversion region or said overlapped address registration region of said address conversion table is updated.