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:
Jul. 07, 1998
Filed:
Aug. 15, 1995
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02M / ; H02M / ; H02M / ; H03K / ;
U.S. Cl.
CPC ...
363124 ; 363 17 ; 363 98 ; 327434 ;
Abstract
A power conversion apparatus has a four terminal semiconductor device including a drain terminal and a source terminal for supplying main current, a gate terminal for controlling the main current, and a base terminal for controlling the on-state voltage, and energy storage means which is connected in the main current circuit consisting of a load and a main power source, wherein electric power is supplied to the base terminal of the semiconductor device by energy stored in the storage means. Because electric power supplied to the base terminal is provided by energy from the main current circuit, the occurrence of power loss in the control circuit to achieve high frequency operation is avoided.