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. 07, 2012
Filed:
May. 02, 2011
Applicants:
Tomoharu Tanaka, Yokohami, JP;
Koichi Kawai, Yokohama, JP;
Khandker N Quader, Sunnyvale, CA (US);
Inventors:
Assignees:
Kabushiki Kaisha Toshiba, Tokyo, JP;
Sandisk Corporation, Sunnyvale, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
G11C 16/04 (2006.01); G11C 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A nonvolatile semiconductor memory device includes a memory cell array constituted by a plurality of memory blocks, an interface, a write circuit, and a read circuit. A protect flag is written in the memory block. The readout protect flag can be output to an external device through the interface. When a write command is input from the interface, the write circuit executes the write command when the protect flag in the selected memory block has a first value and does not execute the write command when the protect flag has a second value.