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:
Jul. 03, 2001
Filed:
Oct. 19, 1998
Terence B. Hook, Jericho Center, VT (US);
Chung H. Lam, Williston, VT (US);
Eric S. Lee, Beaverton, OR (US);
James S. Nakos, Essex Junction, VT (US);
Nivo Rovedo, Lagrangeville, NY (US);
Richard Q. Williams, Essex Junction, VT (US);
Robert C. Wong, Poughkeepsie, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An apparatus and method for detecting a defective array of NVRAM cells. A counter is provided which times an erase time interval for the NVRAM cells during a regular erase function. The computed erase interval is compared with a maximum erase interval to determine at least a first characteristic which indicates the block of NVRAMs is at the end of its useful life. A second characteristic is determined by computing the slope in the erase time function versus the number of simulated erase functions. When the slope of the erase function exceeds a maximum slope, the NVRAM array is determined to be at the end of its useful life.