Importance

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Abstract

A semiconductor memory device includes a redundancy circuit having upper address bit input terminals receiving upper address bit, lower address bit input terminals receiving lower address bits, a regular memory cell array having a plurality of word lines and bit lines, and a plurality of memory cells are arranged at each intersection of the word and bit lines. A redundancy memory cell array is provided having a plurality of word and bit lines, and a plurality of memory cells are arranged at each intersection of the word and bit lines. The capacity of the redundancy memory cell array being smaller than the regular memory cell array. A first selection circuit selects a word or bit line in the regular memory cell array in accordance with the upper and lower address bits. A second selection circuit select a word or bit line in the redundancy memory cell array in accordance with the lower address bits. A redundancy address programming circuit programs the upper address bits corresponding to defective memory cells in the regular memory cell array. A control circuit compares the input upper address bits with the programmed upper address bits and controls the first and second selection circuits to inhibit the selection of the word or bit lines in the regular memory cell array. A predetermined word or bit line in the redundancy memory cell array is selected therefor when each of the input upper address bits coincides with each of the programmed upper address bits.

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First Claim