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:
Oct. 26, 1999
Filed:
Mar. 27, 1997
Applicant:
Inventor:
Teruyuki Shimura, Tokyo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05F / ;
U.S. Cl.
CPC ...
327530 ; 327535 ;
Abstract
A bias circuit for a bipolar transistor includes a constant voltage source connected to a base electrode of the bipolar transistor; and a resistor connected in series between the constant voltage source and the base electrode of the bipolar transistor. By selecting an appropriate resistance for this resistor, the bias point moves due to a change in the voltage drop across the resistor. The change occurs because the base current flowing through the resistor changes, whereby the operating class of the transistor changes, resulting in a high efficiency at a desired output power.