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:
Jun. 13, 2017
Filed:
Dec. 28, 2015
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Yuriko Ishitobi, Osaka, JP;
Hitoshi Suwa, Osaka, JP;
Abstract
A bitwise bidirectionally rewritable nonvolatile semiconductor storage device capable of performing a high-speed data rewrite, while enhancing endurance characteristics and data-retention characteristics of a memory cell. To achieve high-speed generation of rewrite-bit information indicating that a data rewrite is needed or not, the structure employs a logic circuit corresponding to the number of change patterns of write conditions and concurrently compares between read-out data RO of memory at the start of the data rewrite and prepared write data DIN. After an electrical data rewrite of the memory, the data rewrite is verified based on the rewrite-bit information stored in an internal buffer circuit. This protects an already-rewritten memory cell from unnecessary additional rewrite.