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:
Dec. 29, 1998
Filed:
May. 13, 1997
Applicant:
Inventor:
Mitsuru Sekiguchi, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11C / ;
U.S. Cl.
CPC ...
365218 ; 36518533 ; 3651853 ;
Abstract
When floating gate type memory transistors undesirably enter into an over-erased state, a diagnostic potential generator supplies a first diagnostic potential to a source line and second and third diagnostic potentials to non-selected word lines and a selected word line; the potential difference between the first diagnostic potential and the second diagnostic potential causes an over-erased memory transistor to be turned off, and the potential difference between the first diagnostic potential and the third diagnostic potential allows an over-erased memory transistor to turn on so as to identify each over-erased memory transistor by its row and column addresses.