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:
Jan. 31, 2017
Filed:
Apr. 15, 2015
Advantest Corporation, Tokyo, JP;
Advantest Corporation, Tokyo, JP;
Abstract
System and method of selecting defective columns in NAND memory devices for repair. After locating the defective blocks and defective columns in a NAND memory device, a weight value is calculated for each defective block by dividing a total number of defective blocks that would be inherently repaired as a result of repairing the respective defective block by a number of defective data columns in the respective defective block. A defective block with the greatest weight value is selected for repair in which the defective columns in the selected block are substituted by redundant columns. Other defective blocks with defective columns having the same column addresses with the defective columns in the selected defective block are automatically selected for repair as well. Remaining defective columns are selected for repair by iteratively updating weight values and selecting a defective block that has the greatest weight value among the remaining defective blocks.