| 摘要 |
A novel redundancy architecture for an integrated-circuit memory is utilized having no redundancy columns separate from the useful columns but with each useful column, except for the first column, serving as a redundancy column for any adjacent defective column. If a column of order j, normally designated by an output of order j of the column decoder DC, is serviceable, it is actually this column which will be selected by the corresponding output of the decoder DC. On the other hand, if the column is defective, no specialized remote redundancy column will be sought for the repair but instead the output of the decoder will be made to select the following column (order j+1), which would normally have been designated by the following output (order j+1) of the decoder. The other decoder output will be routed towards a third column (order j+2), etc. Therefore, the links between the decoder outputs and the column used will be progressively offset. The memory plane is seen in groups of n+1 columns with the row DR and column DC decoders. A fuse circuit CF designates a defective column. Through the use of this architecture all of the columns can be tested even those which are not being used.
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