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. 25, 1989
Filed:
Dec. 16, 1987
Applicant:
Inventors:
Hirotoshi Tanaka, Yamanashi, JP;
Satoshi Tanaka, Kokubunji, JP;
Taizo Kinoshita, Kokubunji, JP;
Nobuo Kotera, Kokubunji, JP;
Minoru Nagata, Kodaira, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05F / ;
U.S. Cl.
CPC ...
323315 ; 323316 ;
Abstract
A constant current circuit includes a first FET providing an input reference current flow, a second FET providing an output current flow and a non-linear impedance element connected between the drain and the gate of the first FET. By setting a parameter of the non-linear impedance element and a parameter of the first FET to have a specific relationship with each other, the output current can be maintained at a substantially definite value irrespective of relatively large variations of the input reference current.