NONVOLATILE SEMICONDUCTOR MEMORY DEVICE AND BLOCK REDUNDANCY RELIEF METHOD

摘要

PROBLEM TO BE SOLVED: To provide a nonvolatile semiconductor memory device which is highly efficient in actual use of memory blocks and applicable to a dual work function and capable of relieving blocks at high speed. SOLUTION: This memory device has a block replacing means to replace a defective block by a redundant block when one memory block is defective in the memory array. The block replacing means has an address converter circuit 10 in which the block replacing means reverses the address bits of inputted external block address corresponding to the bits where the address bits do not match between the defective block address in the defective block and the address of the redundant block in the address bits to convert into the inner block address. It is built so that each memory block 5 is selected based on the inner block address after converting the external block address inputted from the outside into the address converter circuit 10. COPYRIGHT: (C)2005,JPO&NCIPI