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:
Apr. 07, 2009
Filed:
Nov. 14, 2006
Douglas B. Butler, Colorado, CO (US);
Douglas B. Butler, Colorado, CO (US);
ProMOS Technologies PTE.Ltd, Singapore, SG;
Abstract
A DRAM refresh period adjustment technique based on the retention time of one or more unused memory cell(s) having characteristics very similar to the characteristics of the memory cell(s) with the shortest retention time used in the DRAM array. In a particular implementation of the technique of the present invention, the refresh period of a DRAM array is adjusted through the use of one or more of the DRAM bits that fail to meet the retention time requirement and have, therefore, been replaced by redundant DRAM bits. These replaced bits are then used to indicate the refresh period for the DRAM is the maximum it can be for the DRAM under then current operating conditions.