Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Renesas Technology Corp.

Shin Chaki

Yasuharu Nakajima

Yoshinobu Sasaki

Yoshihiro Tsukahara

Takashi Yamasaki

Takaaki Yoshioka

Kunihiro Sato

Ko Kanaya

A flexible substrate () is bent at a bending part (). A dielectric plate () has first and second main surfaces opposite to each other. A high-frequency signal line () is provided on the first main surface of the dielectric plate (). A ground conductor () is provided on the second main surface of the dielectric plate (). The high-frequency signal line () and the ground conductor () form a micro strip line. A local absent part () facing the high-frequency signal line () is provided on the ground conductor () only at the bending part ().

Flexible substrate

A high-frequency circuit includes: a first substrate; a transmission line formed on the first substrate and having first and second output portions branched from an input portion; a second substrate; first and second pads formed on the second substrate; a first wire connecting the first output portion to the first pad; and a second wire connecting the second output portion to the second pad, wherein an electrical length from the input portion to an edge of the second output portion is longer than an electrical length from the input portion to an edge of the first output portion, and a length from a junction between the second wire and the second output portion to the edge of the second output portion is longer than a length from a junction between the first wire and the first output portion to the edge of the first output portion.

High-frequency circuit

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.

High-frequency power amplifier and method for manufacturing the same

A high frequency characteristic measuring device for measuring high frequency characteristics of a high frequency device to be measured by contacting probe needles with the high frequency device to be measured, before mounting of the high frequency device to be measured. The high frequency characteristic measuring device includes an input matching circuit substrate with an input matching circuit thereon, a first coaxial connector electrically connected to the input matching circuit substrate, and first probe needles electrically connected to the input matching circuit substrate. The high frequency characteristic measuring device further includes an output matching circuit substrate with an output matching circuit thereon, a second coaxial connector electrically connected to the output matching circuit substrate, and second probe needles electrically connected to the output matching circuit substrate.

High frequency characteristic measuring device

A power amplifier includes a power distribution circuit which distributes an input signal into signals and outputs the signals, amplification circuits which amplify the respective signals outputted from the power distribution circuit, a power combining circuit which combines the respective signals outputted from the amplification circuits and outputs the combined signal, and a stabilization circuit connected to an input line of the power distribution circuit. The stabilization circuit has a capacitance and a resistance connected in parallel.

Power amplifier

A radio-frequency power amplification circuit includes a transistor and a stablization circuit that is provided upstream of the transistor. The stabilization circuit includes a series resistor, a first end of which is connected to the transistor and a second end of which is connected to an input terminal, a resistance element, a first end of which is connected to the second end of the series resistor, and a short stub, a first end of which is connected to the second end of the resistance element and the second end of which is grounded via a capacitance element.

Radio-frequency power amplification circuit having stabilization circuit

An attenuator with a simple circuit configuration is and accurate attenuation includes four transistors connected in parallel between a connecting point on a main line and a ground. Since the transistors are individually brought into an 'ON' state and an 'OFF' state to function as &#x201c;resistors&#x201d; or &#x201c;capacitors&#x201d;, a desired attenuation be obtained by combinations of the ON and OFF states of the respective transistors.

Attenuator with switchable transistors for controlling attenuation

A high frequency semiconductor integrated circuit includes a main circuit, a circuit block, a pad, and a wire. The main circuit includes an input terminal, a transistor, transmission lines, a pad, and an output terminal. The circuit block includes a passive circuit and a capacitor. The pad is disposed close to the circuit block. The wire connects the pad to the pad included in the main circuit. In the high frequency semiconductor integrated circuit, the main circuit outputs an input signal input at the input terminal from the output terminal through the transistor, the transmission line, the pad, and another transmission line. As a result, the high frequency semiconductor integrated circuit can realize various performances and can be used in many applications.

High frequency semiconductor integrated circuit capable of switching between characteristics

Three or more MESFETs are fabricated side by side on a semiconductor chip. A transmission line substantially identical in width with an area within which the MESFETS are fabricated is formed in parallel with the row of MESFETs. The MESFETs are connected to the transmission line at a side, constituting one edge of the transmission line. Further, regulation circuits are connected in shunt with the transmission line, and outputs of the MESFESTS are merged while being matched by the transmission line and the regulation circuits.

Semiconductor device

To eliminate variations in measurement of the chip characteristics an MMIC chip has a pad main portion having the same width as a main line at an end of the main line The main line is located on a GaAs substrate. Pad auxiliary islands are adjacent to the pad main portion on one or both sides. A grounding wiring layer is on at least one side of the pad main portion with the pad auxiliary island interposed in between. The pad main portion and the pad auxiliary portions secure a sufficient bonding area. The electrical characteristics are measured by bringing probes into contact with the pad main portion and the grounding wiring layer(s). The electrical characteristics of the MMIC chip can be evaluated without an increase in bonding pad capacitance.

RF circuit chip and RF circuit device including the RF circuit chip

An amplifier with a temperature compensation function featuring a simple configuration wherein a high frequency signal attenuation circuit is connected to a gate terminal of an amplifying active device. The high frequency signal attenuation circuit uses the source terminal and the drain terminal of a compensating active device as input and output terminals, and the gate terminal is grounded.

Amplifier with temperature compensation function

The present invention provides a high frequency amplifier circuit and a microwave integrated circuit which allow easy development of various models having different operating frequencies and other properties and improve the yield of production. The high frequency amplifier circuit of the present invention comprises a high frequency transistor and a matching circuit connected between a terminal of the transistor and an external connection terminal, wherein the matching circuit has a variable capacitive element of which one end is connected to a terminal of the transistor and the other end is connected to the external connection terminal, and a short stub of which one end is connected to the other end of the variable capacitive element and the other end is directly grounded.

High frequency amplifier circuit and microwave integrated circuit

A microwave integrated circuit includes a matching circuit for electromagnetic analysis in designing the circuit. The matching circuit is a T-junction circuit comprising distributed constant lines. Miniaturization of the microwave integrated circuit is realized while reducing the time required for electromagnetic analysis and improving design precision by using meandered distributed constant lines.

Growing community of inventors

Tokyo, Japan

Shin Chaki