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. 10, 2003
Filed:
Mar. 05, 2001
Takao Moriwaki, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A high-frequency semiconductor amplifier circuit minimizing deterioration of high-frequency characteristics and attaining high thermal stability. A driver stage of a power amplifier has a multi-stage configuration with multi-finger HBTs connected in shunt with each other, each multi-finger HBT having a single emitter. An output stage has a single stage configuration multi-finger HBTs connected in shunt with each other, each HBT including two emitters. As a result, while an increase in capacitance of a p-n junction between an emitter layer and a base layer of the driver stage is prevented, thermal nonuniformity arising in the output stage is minimized. Thus, a power amplifier as a whole is configured with high thermal stability without deterioration of a high-frequency characteristic of the power amplifier.