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. 04, 1991
Filed:
Apr. 01, 1988
John A Fifield, Jericho, VT (US);
Steven W Tomashot, Jericho, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A semiconductor memory device is described in which wordline redundancy is implemented without impacting the access time. A redundant decoder circuit generates a wordline drive inhibit signal which inhibits the generation of a normal wordline signal. Deselection also deselects the normally accessed reference cells, requiring that the redundant cells provide their own reference signal. This last requirement is accomplished by utilization of twin cells for the redundant memory. Placing the redundant memory cells on the sense node side of the bit line isolators enables the effective doubling of the number of redundant cells available each of a plurality of sub-arrays of normal memory.