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:
Dec. 29, 1987
Filed:
Aug. 09, 1984
Applicant:
Inventors:
Naoki Sato, Hachioji, JP;
Yoshihisa Kamo, Kokubunji, JP;
Yasuhiro Katoh, Tokyo, JP;
Minoru Kosuge, Odawara, JP;
Shinichi Arai, Odawara, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03K / ; H03K / ; H03K / ;
U.S. Cl.
CPC ...
3072 / ; 307308 ; 307494 ;
Abstract
A circuit for detecting the variation of resistance of a variable-resistance element comprises a pair of grounded-base transistors with their base electrodes provided with different base voltages and with their emitter electrodes connected to both terminals of the variable-resistance element so that the voltage between both terminals of the element is kept constant. The current density of the variable-resistance element does not vary when the resistance of the variable-resistance element varies, whereby the lifetime of the element can be prolonged.