Mitsubishi Electric Corporation

Takaaki Yoshioka

Koji Yamanaka

Shintaro Shinjo

Masatake Hangai

Takashi Yamasaki

Yuji Komatsuzaki

Shin Chaki

Shinichi Miwa

Shohei Imai

Masaharu Hattori

Keigo Nakatani

Kenji Harauchi

Kunihiro Sato

An amplifier includes: a high-frequency input terminal; a high-frequency output terminal; a multistage circuit provided between the high-frequency input terminal and the high-frequency output terminal and including two or more amplifiers and connected in series, each amplifier including an input matching circuit, a transistor, and an output matching circuit; a stabilizing circuit provided in at least two of the amplifiers and including a bandpass filter and a resistor connected in parallel; and a band-rejection filter provided between the at least two of amplifiers and eliminating a frequency lower than an operation frequency of the amplifier. The stabilizing circuit and the band-rejection filter are provided between an output terminal of the transistor of the amplifier and the output matching circuit or provided in the output matching circuit. The closer to the high-frequency input terminal the bandpass filter is, the lower a resonance frequency of the bandpass filter is.

High-frequency, multistage, low-noise amplifier

A power amplifier includes: plural amplifiers; a tournament-tree-shaped circuit connected with the plural amplifiers and including plural transmission lines arranged in a tournament-tree shape; and plural difference frequency short circuits shunt-connected with plural nodes of the tournament-tree-shaped circuit, wherein each of the plural difference frequency short circuits includes an inductor and a capacitor connected in series, resonant frequencies of the plural difference frequency short circuits become lower as the plural difference frequency short circuits are more separated from the plural amplifiers, and the difference frequency short circuits having equivalent resonant frequencies are connected with plural nodes in the same stage among the plural nodes.

Power amplifier

An amplifier includes: a circuit pattern providing a plurality of signal paths having different lengths; a transistor chip; a plurality of pads of transistor cells, the pads being electrically connected to the circuit pattern and being arranged on the transistor chip; a plurality of the transistor cells; a plurality of transmission lines for connecting each of the plurality of pads and each of the plurality of transistor cells, the transmission lines being arranged on the transistor chip, and a plurality of harmonic processing circuits each connected to each of the plurality of transmission lines and arranged on the transistor chip. The plurality of harmonic processing circuits each has a capacitor and an inductor, and a product of the capacitance of the capacitor and the inductance of the inductor is made constant in each of the plurality of harmonic processing circuits.

Amplifier

A high-frequency power amplifier is configured to include plural island patterns () in which ends thereof are arranged in the vicinity of a transmission line () and other ends thereof are arranged in the vicinity of an end line () in a transmission line (), a wire () for connecting an end of an island pattern () and the transmission line (), and a wire () for connecting another end of the island pattern () and the end line () of the second transmission line (), so that a mismatch of the impedance component having a resistance component and a reactance component can be compensated for by changing the number of first connecting members and the number of second connecting members, the first and second connecting members configured to connect an island pattern () to the transmission lines () and ().

High-frequency power amplifier

A first stabilizing circuit () is disposed between a first transistor () and a first output matching circuit () in a first stage. A second stabilizing circuit () is disposed between a second transistor () and a second output matching circuit () in a second stage. The first stabilizing circuit () includes a first band-pass filter and a first resistor () connected in parallel. The first band-pass filter allows a signal of a frequency flower than a central frequency fc of the operation frequencies as an amplifier to pass through. The second stabilizing circuit () includes a second band-pass filter and a second resistor () connected in parallel. The second band-pass filter allows a signal of a frequency fhigher than the central frequency fc to pass through.

Multi-stage high frequency amplifier

A Wilkinson power divider includes: &#x3c0;-type LPFs connected to an input terminal; a T-type HPF having one end connected to one of the &#x3c0;-type LPFs and having another end connected to a carrier amplifier; another T-type HPF having one end connected to another one of the &#x3c0;-type LPFs and having another end connected to a &#x3bb;/4 line; and an isolation resistor connected to connection points.

Doherty amplifier

Two rows of resistive bodies, first resistive body and second resistive body, having slits are provided on an input matching circuit substrate. Since a high-frequency signal flows through not only the resistive bodies but also a transmission line pattern formed in the slits, the burnout of the resistive bodies can be prevented.

Semiconductor device

A high frequency device includes a base plate having a main surface, a dielectric on the main surface, along a first side of the base plate, a signal line on the dielectric and extending from the first side toward a central portion of the main surface, an island pattern of a metal on the dielectric, a metal frame having a contact portion contacting the main surface and a bridge portion on the signal line and the island pattern, together enclosing the central portion, a lead frame connected to an outside signal line of the signal line and which is located outside the metal frame, a semiconductor chip secured to the central portion, and a wire connecting the semiconductor chip to an inside signal line of the signal line and which is enclosed within the metal frame.

High frequency device

A high-frequency power amplifier includes: a semiconductor substrate; transistor cells separated from each other and located on the semiconductor substrate; and testing electrodes respectively connected to individual transistor cells, wherein an electrical signal and power to individually operate each corresponding transistor cell are supplied to each transistor cell, independently, from outside, using the testing electrodes.

Growing community of inventors

Tokyo, Japan

Takaaki Yoshioka