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:
Aug. 23, 1994
Filed:
Sep. 09, 1993
Applicant:
Inventor:
Masataka Takebuchi, Yokohama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11C / ;
U.S. Cl.
CPC ...
365185 ; 36518909 ; 36518911 ; 365218 ;
Abstract
A non-volatile semiconductor memory device includes a voltage supply circuit for supplying a positive voltage to the source line or bit line (to which a low biasing voltage is conventionally applied) with respect to each of non-volatile memory cells in a memory cell array in a data read mode. Since this voltage supply circuit applies the positive voltage to the memory cells in the data read mode, an effect equivalent to back gate biasing of the memory cells can be achieved. Accordingly, a memory cell in an overerase state has, a positive threshold voltage in the data read mode.