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:
Feb. 07, 1995
Filed:
Jul. 02, 1993
Applicant:
Inventor:
Makoto Ihara, Sakurai, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11C / ; G11C / ;
U.S. Cl.
CPC ...
365200 ; 365201 ; 365230030 ;
Abstract
The semiconductor memory device according to this invention includes both ROM cells and RAM cells mixed on one line of memory cells. The semiconductor memory device further has a redundant ROM bit line and a redundant RAM bit line. An address on the redundant ROM or RAM bit line is selected in accordance with whether the corresponding address on a defective line to be replaced with the redundant ROM or RAM bit line is a RAM or a ROM. Therefore, it is possible to redundantly recover a defective line including both ROMs and RAMs. Further, a semiconductor memory device including ROMs and RAMs mixedly can be produced in a high yield.