Non volatile semiconductor memory device having a multi-bit cell array

摘要

A semiconductor device is provided. The semiconductor device includes a storage part storing an address for weak cells in a nonvolatile state; and a dynamic semiconductor memory device including: a memory cell array having normal cells and the weak cells to be refreshed; and a refresh control part performing a refresh operation for the weak cells, wherein a refresh period for the weak cells is shorter than a refresh period for the normal cells when the address applied in a refresh operation mode coincides with the address stored in the storage part.