Static information storage and retrieval – Read/write circuit – Bad bit
Patent
1995-06-06
1997-09-09
Nelms, David C.
Static information storage and retrieval
Read/write circuit
Bad bit
36523003, 36523006, G11C 700
Patent
active
056663145
ABSTRACT:
A semiconductor memory device has 2.sup.n word lines, a plurality of bit lines, a plurality of nonvolatile memory cells disposed at each intersection of the word lines and the bit lines, a write circuit for writing data to a memory cell located at an intersection of selected ones of the word lines and the bit lines, and a sense amplifier for reading data out of the memory cells. Further, the semiconductor memory device comprises a first unit for simultaneously selecting a block of 2.sup.m (n>m) word lines among the 2.sup.n word lines, and a second unit for not selecting a block of 2.sup.k (m>k) word lines among the 2.sup.m word lines. The second unit does not select the block of 2.sup.k word lines, and selects a block of 2.sup.k word lines prepared outside the 2" word lines when any one of the 2.sup.k word lines among the 2.sup.m word lines is defective. Consequently, redundant word lines are effectively employed, write and verify operations are stable, and thereby the yield and performance of the semiconductor memory device are improved.
REFERENCES:
patent: 4757474 (1988-07-01), Fukushi et al.
patent: 5233559 (1993-08-01), Biennan, Jr.
patent: 5289417 (1994-02-01), Ooishi et al.
patent: 5297085 (1994-03-01), Choi et al.
patent: 5297148 (1994-03-01), Harari et al.
patent: 5307316 (1994-04-01), Takemae
Akaogi Takao
Itano Kiyoshi
Kasa Yasushi
Kawashima Hiromi
Takashina Nobuaki
Fujitsu Limited
Le Vu A.
Nelms David C.
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