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:
Apr. 28, 1992
Filed:
Dec. 27, 1989
Applicant:
Inventor:
Ichiro Kondo, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
357 235 ; 357 2314 ; 357 45 ; 365201 ; 324523 ;
Abstract
A test circuit is incorporated in a semiconductor memory device including at least one ultraviolet erasable and electrically programmable non-volatile memory cell having a control gate and a floating gate. The test circuit comprises a switching circuit for selectively supplying the control gate of the memory cell with a voltage which is higher than a power supply voltage for ordinary reading a content of the memory cell, through a write voltage supply line used for writing data to the memory cell. The switching circuit makes it possible to test the written state of the memory cell with a voltage different from the normal reading power supply voltage.