Mitsubishi Electric Corporation

Eigo Kuwata

Makoto Kimura

Koji Yamanaka

Shintaro Shinjo

Dai Ninomiya

Hiroshi Otsuka

Hidenori Ishibashi

Masaomi Tsuru

Akira Ohta

Kazuhiko Nakahara

Akihito Hirai

Yoshitaka Kamo

Kiyoshi Ishida

Jun Nishihara

Yukinobu Tarui

Kazuhiro Iyomasa

Yutaro Yamaguchi

Hiroyuki Nonomura

Shohei Imai

Hiroaki Maehara

Hideharu Yoshioka

Osamu Wada

Jun Kamioka

Hiroyuki Aoyama

Tasuku Kirikoshi

A high-efficiency amplifier is configured so that short stubs are provided in a line between a first substrate end and a second substrate end of a substrate, and among the short stubs, short stubs provided at locations other than both ends of the line include two short stubs and which are adjacent to each other, and which are provided at locations at which the two short stubs are to be electromagnetically coupled to each other.

High-efficiency amplifier

An amplifier is configured in such a way that a first capacitor resonates at the frequency of a second harmonic wave included in a signal outputted from an amplifying element, a circuit including a second transmission line, the first capacitor, and a second capacitor resonates at the frequency of a third harmonic wave included in the signal outputted from the amplifying element, and also matches the impedance for a fundamental wave together with an impedance matching circuit.

Amplifier

A dielectric heating device is provided with two or more electrodes, a grounded surface connected to a first electrode, a signal source connected to a second electrode to output a high-frequency signal, a first element interposed serially between the signal source and second electrode, and a second element interposed serially between the grounded surface and first electrode. The first element includes two terminals that electrically connect the signal source and second electrode in a non-contact manner, to cause the high-frequency signal outputted from the signal source to pass through the first element, by using the electric coupling between the two terminals. The second element includes two terminals that electrically connect the grounded surface and first electrode in a non-contact manner, to output, by using the electric coupling between the two terminals, the high-frequency signal outputted from the signal source, to the grounded surface.

Dielectric heating device and dielectric heating electrodes

A MIM capacitor is included in any one or more of a first matching circuit and a second matching circuit. The mat capacitor performs impedance matching of a fundamental wave included in a high-frequency signal with a transmission line, and forms a short-circuit point for a harmonic included in the high-frequency signal at a connection point with the transmission line.

High-frequency amplifier

When a potential difference Vbetween a source terminal of an E-type FET () and a source terminal of a D-type FET () is larger than a threshold voltage V, a protection circuit () starts an operation to reduce the potential difference Vsuch that the potential difference Vis smaller than the threshold voltage V. This makes it possible to prevent destruction of the E-type FET () even when a signal to be amplified is an RF signal.

High frequency amplifier

A control circuit () is configured to detect the impedance Pof a load () and control each of the reactance value Lof a first variable reactance element (), the reactance value Lof a second variable reactance element (), and the phase shift amount &#x3c6; of a phase shifter () on the basis of the detected impedance P. Consequently, impedance matching can be achieved even with the phase shifter () that performs discrete phase shift control.

Impedance tuner and signal amplification device

A printed wiring board includes conductor layers, a core layer having an opening, and a build-up layer. A high frequency device placed within the opening is installed such that a mirror surface is thermally connected to a conductor layer for heat dissipation facing the opening from a lower surface side of the core layer, and terminals on the terminal surface are electrically connected to conductor layers formed on an upper surface side of the core layer.

High frequency circuit

A multi-finger transistor includes a circuit suppressing a variation in voltage current distribution. The circuit connects gate fingers () to each other, or source fingers () to each other in a region which is located outside an active region () and on a side where a drain pad () is disposed. The multi-finger transistor is configured to be linearly symmetric with respect to a direction of propagation of a signal from a gate pad () at the position of the gate pad ().

Multi-finger transistor and semiconductor device

Parallel capacitors (and) of impedance matching circuits () which are connected to two transistors (), respectively, have their first ends connected to a ground through via holes (and) that are used in common, respectively. Although a conventional circuit necessitates via holes by the number equal to the number of stages multiplied by the number of cells of the transistors () for an LPF type impedance matching circuit (), the present circuit can halve the number of via holes of the LPF type impedance matching circuit (), thereby being able to downsize the circuit.

Growing community of inventors

Tokyo, Japan

Eigo Kuwata