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. 16, 2002
Filed:
Jul. 25, 2001
Applicant:
Inventor:
Yoshitaka Mano, Kyoto, JP;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C 1/122 ;
U.S. Cl.
CPC ...
G11C 1/122 ;
Abstract
To provide a ferroelectric memory, in which data can be positively protected even in an event of fluctuations in process parameter, time can be shortened for a reliability estimation test, and it is possible to avoid device breakage resulted from the test. A source voltage VDD is detected by using a source voltage detection circuit having a stable detection level. When a detected voltage RREFA is at or lower than a set detection level VREFA, an external input terminal XEXTCE is deactivated by using an output signal of a differential amplifier circuit to protect data. Thus, it is possible to protect data with stability.