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. 12, 2000
Filed:
May. 28, 1999
Masayoshi Hirata, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In an erasing device or method for a storage unit, or a storage medium storing a program for erasing the storage unit, an output VS of a column decoder and a reference voltage VR are compared at a sense amplifier, while an erase operation is executed by taking out an electric charge of each cell in a memory cell array, after which the output of the sense amplifier is evaluated at a data determination circuit, and a signal DD is counted by a bit counter under the condition of VS<VR. As the entirety of addresses of an address signal ADD from an internal address increment circuit are finished, a signal FG rises. When a count number of a bit counter is above a predetermined number, an erasing routine is terminated, and thus it is possible to prevent the majority of the bits from falling into a state of depression.