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:
Feb. 23, 2016
Filed:
Dec. 03, 2014
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Yasushi Nakajima, Kawasaki, JP;
Yuki Yamamura, Yokohama, JP;
Yuki Kanamori, Kamakura, JP;
Kenri Nakai, Fujisawa, JP;
KABUSHIKI KAISHA TOSHIBA, Minato-ku, JP;
Abstract
A nonvolatile semiconductor memory device according to an embodiment comprises a control unit, in a data write, determining at least one of: a first requirement that the number of times of a data read on first through n-th pages (where nis an integer of 1 to N−1) of a target block executed after the most recent data erase on the target block, is less than a reference number of times; and a second requirement that the number of memory cells whose threshold voltage is higher than a reference voltage, of a plurality of memory cells of a reference page of n+1-th through N-th pages of the target block, is less than a reference number, and when the determined requirement is satisfied, writing additional data to the n+1-th through N-th pages of the target block.