The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 11, 1991
Filed:
Jul. 12, 1990
Applicant:
Inventors:
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C / ;
U.S. Cl.
CPC ...
365200 ; 365185 ; 365210 ;
Abstract
An improved semiconductor memory device having a memory array, a dummy cell and a redundancy cell column is disclosed. At least one dummy capacity cell is connected to the reference bit line to which the dummy cell is connected, and also to a redundancy bit line to which redundancy cells are connected. Therefore, since a capacity on the reference bit line is roughly equalized to that on the redundancy bit line by these dummy capacity cells, it is possible to prevent erroneous potential level determination by a sense amplifier for comparing both the potentials on both the bit lines, without being subjected to the influence of supply voltage fluctuations.