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. 15, 2020
Filed:
Jul. 03, 2019
Denso Corporation, Kariya, JP;
Koichi Yako, Kariya, JP;
Yoshiaki Nakayama, Kariya, JP;
DENSO CORPORATION, Kariya, JP;
Abstract
A data erasure device is for a non-volatile semiconductor memory device, which includes cells in which data is written by an application of a first voltage and erased by an application of a second voltage differing from the first voltage. The data erasure device includes a controller. The controller applies a second voltage to the cells over first time period with multiple occurrences to set the cells into a first erasure state, and applies the second voltage to the cells over second time period, which is longer than the first time period, to set the cells in a second erasure state deeper than the first erasure state. The controller changes a number of occurrences of applying the second voltage over the first time period to each of the cells or each of multiple cell groups having the cells according to respective erasure states of the cells.