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:
Oct. 19, 1999
Filed:
Jul. 13, 1998
Applicant:
Inventors:
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C / ; G11C / ; G11C / ;
U.S. Cl.
CPC ...
365200 ; 36518905 ; 36523008 ;
Abstract
A semiconductor memory device according to the present invention includes a block determining portion determining a difference in arrangement between a normal cell and a spare cell which replaces it, a data scramble controlling circuit generating a scramble ON signal when a normal cell is replaced by a spare cell and the spare cell stores inverted data, a scramble circuit inverting data to be written in response to the scramble ON signal, and a scramble circuit inverting data to be read in response to the scramble ON signal.