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:
Sep. 11, 2001
Filed:
Jun. 22, 2000
Shoichi Kawamura, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A non-volatile semiconductor memory device comprises a plurality of memory cell units each of which includes a plurality of non-volatile memory cells capable of having data electrically rewritten; a storage unit; and an access inhibiting circuit. The storage unit stores therein the defect information of the memory cell unit not normally operating. The access inhibiting circuit judges the condition of the memory cell unit within the device according to the defect information stored in the storage unit. Access to the memory cell unit not normally operating is inhibited in accordance with the result of the judgement. Since the device can control the information of the memory cell unit not normally operating by itself, users of the device need not manage the defective memory cell unit. Consequently, the usability of the device is enhanced and the cost of a system mounting the device is curtailed. Particularly, it is effective for the non-volatile semiconductor memory device for file allowing the presence of inoperative memory cells.