摘要 |
<p>A semiconductor memory unit comprising a plurality of main memory blocks formed on a chip and respectively having redundant cells, a plurality of auxiliary memory blocks formed on the chip and having substantially the same structure as the main memory block, a memory circuit for storing the address of a main memory block having a defect which cannot be restored by redundant cells, and a redundant control circuit for selecting an auxiliary memory block when a defective main memory block is selected. <IMAGE></p> |