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:
Jul. 24, 2001
Filed:
May. 18, 2000
Shoichi Kawamura, Kawasaki, JP;
Fujitisu Limited, Kawasaki, JP;
Abstract
The present invention is a nonvolatile semiconductor memory having, in addition to a main storage region for storing ordinary data, a hidden storage region for storing a special code for preventing unauthorized copying, and this hidden storage region is in a read enabled state at the time of a write protected state, and is in a read prohibited state at a time when there is no write protected state. Therefore, a hidden storage region can be read out only after a semiconductor memory vendor stores a special code in a hidden storage region, and sets the hidden storage region to a write protected state. And the method for changing to this write protected state is a secret to everyone other than the vendor. As a result thereof, even if a semiconductor memory, for which a special code is not stored in a hidden storage region, is illegally obtained on the black market, since hidden storage region readout is still prohibited, illegally copied data cannot be used, consequently preventing unauthorized copying.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile