Mitsubishi Electric Corporation

Hiromitsu Utsumi

Takayuki Matsuzuka

Tetsuo Kunii

Katsumi Miyawaki

Junichi Udomoto

Suguru Maki

Hiroaki Minamide

A transistor () and a matching circuit substrate (-) are provided on a base plate () and connected to each other. A frame () is provided on the base plate () and surrounds the transistor () and the matching circuit substrate (-). The frame () has a smaller linear expansion coefficient than that of the base plate (). A screwing portion () is provided in the frame (). A size of the base plate () is smaller than that of the frame ().

Semiconductor package

A power amplifier includes: an amplifier; an input matching circuit connected to an input of the amplifier; an output matching circuit connected to an output of the amplifier; and a low-frequency processing circuit connected to the input matching circuit or the output matching circuit, wherein the low-frequency processing circuit includes a first line having a first end connected to the input matching circuit or the output matching circuit, a first shot stub connected to a second end of the first line and including a second line and a first capacitor connected in series each other, and a second short stub connected to the second end of the first line in parallel with the first short stub and including a third line and a second capacitor which are connected in series each other, the first line has a length of &#x3bb;/8, the second line has a length of &#x3bb;/4, and the third line has a length of &#x3bb;/8 with respect to a wavelength &#x3bb; of a fundamental frequency.

Power amplifier

An internal matching transistor comprises: a conductive base material including a groove, a first region, and a second region which is located opposite to the first region across the groove; a transistor bonded onto the first region of the base material; an internal matching circuit bonded onto the second region of the base material; a wire connecting the transistor to the internal matching circuit across above the groove; and a conductive or non-conductive material located between the wire and the groove, wherein capacitance between the wire and the base material is adjusted by the material.

Growing community of inventors

Tokyo, Japan

Hiromitsu Utsumi