| 摘要 |
PROBLEM TO BE SOLVED: To improve a yield by adding a function of disabling a spare element to a redundancy control circuit for selecting which of an element and the spare element is to be used. SOLUTION: When a fuse of a disable fuse latch circuit 43 in a redundant word line-selecting circuit is cut once, it generates a state in which a (Vss) level is outputted. Irrespective of a state of the other fuse latch circuits and a state of address signals, an output signal of a logic circuit 45, namely, a signal ordering to activate a redundant word line becomes the Vss level at all times. In consequence of this, a redundant word line corresponding to the redundant word line-selecting circuit including the latch circuit 43 with the fuse cut cannot be used any more. When a redundant memory cell used as a replacement comes to fail, the failing redundant memory cell is disabled and then replaced with a different redundant memory cell not used yet.
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