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, 1995
Filed:
Apr. 25, 1994
Kikuzo Sawada, Tokyo, JP;
Yoshikazu Sugawara, Tokyo, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
A non-volatile semiconductor memory device capable of electrical programming including a plurality of memory cells, means for selecting at least one memory cell from the plurality of memory cells, mode setting means for setting one of a first read mode in which data written in the selected memory cell is read and a second read mode for detecting a change of the threshold voltage level of the selected memory cell, first comparing means for comparing a voltage signal read from the selected memory cell with at least a predetermined single first reference voltage level when the first read mode is set, first output means for producing a signal indicative of data written in the selected memory cell on the basis of the comparison in the first comparing means, second comparing means for comparing the cell voltage signal with at least a predetermined single second reference voltage level different from the first reference voltage level when the second read mode is set, and second output means for producing a signal indicative of a change of the threshold voltage of the selected memory cell on the basis of the comparison in the second comparing means.