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:
Jun. 21, 1977
Filed:
Aug. 28, 1975
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., , JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05F / ;
U.S. Cl.
CPC ...
323-4 ; 331186 ;
Abstract
A constant-current circuit has a depletion type FET and a series circuit consisting of an impedance element and an enhancement type FET connected in parallel between two terminals. The gate electrodes of the respective FET's are connected to a juncture between the impedance element and the enhancement type FET, and current which flows through the depletion type FET is set to be sufficiently larger than a current which flows through the series circuit. The voltage across the enhancement type FET is made substantially equal to a threshold voltage thereof, whereby the constant current characteristics of such constant-current circuits are checked from being dispersed.