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. 05, 2016
Filed:
Mar. 02, 2014
Applicant:
Kabushiki Kaisha Toshiba, Tokyo, JP;
Inventors:
Assignee:
Kabushiki Kaisha Toshiba, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C 11/34 (2006.01); G11C 11/56 (2006.01); G11C 16/04 (2006.01); G11C 16/34 (2006.01);
U.S. Cl.
CPC ...
G11C 11/5628 (2013.01); G11C 16/0483 (2013.01); G11C 16/3431 (2013.01); G11C 16/3459 (2013.01);
Abstract
A nonvolatile semiconductor memory device includes a memory cell array having nonvolatile memory cells in which one of multiple values is programmable therein by setting one of a plurality of threshold values therein and a control circuit that performs a writing operation on the memory cells. The writing operation performed by the control circuit includes a pre-programming verification operation to determine a threshold level of a memory cell in an erasure state, and a program operation in which a program voltage is selected from a plurality of program voltages on the basis of a determination result of the pre-programming verification operation.