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:
Oct. 22, 2013
Filed:
Nov. 19, 2008
Yasuhiko Honda, Hiratsuka, JP;
Ryu Hondai, Yokohama, JP;
Manabu Satoh, Kanagawa-Ken, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A method for controlling a threshold value in a nonvolatile semiconductor memory device, includes: performing writing at least once on at least one of the memory cells to be adjusted to a state other than an erased state with an applied voltage that does not cause excess writing, with verify reading being not performed; and performing verify reading by applying a verify voltage corresponding to a target threshold value of the memory cell after the writing is performed on the at least one of the memory cells to be adjusted to the state other than the erased state, and, when the threshold value of the memory cell is determined to be lower than the target threshold value, repeating the writing with the applied voltage that does not cause excess writing and the verify reading until the threshold value of the memory cell becomes equal to or higher than the target threshold value.