Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Noboru Negoro

Hiroyuki Sakai

Takeshi Fukuda

Tetsuzo Ueda

Daisuke Ueda

Koji Takahashi

Manabu Yanagihara

Daisuke Shibata

Hidekazu Umeda

Kenichi Inoue

Takeshi Azuma

Nanako Hirashita

A gate drive circuit that drives a switching element including a first drain, a first source, and a first gate includes: a first terminal to which a gate control signal is input; a gate signal line connecting the first terminal and the first gate; a resistance element inserted in the gate signal line; a capacitance element connected in parallel with the resistance element; a clamp circuit that performs a clamp operation of clamping a voltage between the first gate and the first source to a voltage lower than a threshold voltage of the switching element when the gate control signal indicates an off period of the switching element; and a clamp control circuit that controls whether to prohibit the clamp operation of the clamp circuit in the off period.

Gate drive circuit, gate drive device, high-frequency power supply device, and system

A nitride semiconductor device includes: a substrate; a buffer layer formed on the substrate; a laminated body formed by two or more cycles of semiconductor layers each including a first nitride semiconductor layer, and a second nitride semiconductor layer having a larger band gap than a band gap of the first nitride semiconductor layer, the first and second nitride semiconductor layers being laminated in this order on the buffer layer; a first electrode; and a second electrode. A channel layer is formed in each of the semiconductor layers at an interface between the first nitride semiconductor layer and the second nitride semiconductor layer. A carrier concentration of the channel layer in the uppermost semiconductor layer is lower than a carrier concentration of each of the channel layers of the other semiconductor layers.

Nitride semiconductor device

A semiconductor device includes a substrate; a carrier traveling layer formed on the substrate, made of first group III nitride semiconductor, and containing carriers traveling in a direction along a principal surface of the substrate; a barrier layer formed on the carrier traveling layer and made of second group III nitride semiconductor having a wider band gap than the first group III nitride semiconductor; and an electrode formed on the barrier layer. The device further includes a cap layer formed on the barrier layer at a side of the electrode, and made of third group III nitride semiconductor containing a mixture of single crystals and polycrystals.

Semiconductor device and method of manufacturing the device

The spread spectrum radar apparatus in the present invention (i) includes: a transmission code generator (); a reception code generator () generating a reception code obtained by delaying a transmission code; a spread modulator () spread-modulating a signal generated by a local oscillator () using the transmission code; a transmission antenna () transmitting the spread-modulated signal; a reception antenna () receiving a signal; a spread demodulator () demodulating the signal using the reception code to provide a correlation signal; a mixer () mixing the correlation signal and the signal generated by the local oscillator () to generate a radar signal; a virtual image determining unit () determining a virtual image; and a radar signal calculation device () calculating the radar signal using a virtual image determination signal, and (ii) adds a calculation and an offset signal for suppressing a peak intensity of the virtual image when the virtual image occurs.

Spread spectrum radar apparatus, method for determining virtual image, and method for suppressing virtual image

The code generation apparatus includes: a clock generator which generates a clock signal of a first frequency; a timing controller which generates a timing signal of a second frequency lower than the first frequency; a code table storage in which a plurality of code sequences serving as a source for a pseudo-noise code is stored; an address controller which selects, according to the timing signal, a code sequence to be read, from among a plurality of code sequences; a partial code sequence extractor which extracts, as a partial code sequence, a code of a predetermined length, from the code sequence to be read; and a parallel-series convertor which outputs the partial code sequence one bit at a time, according to the clock signal.

Code generation apparatus

The radar system includes: a transmission circuit transmitting the radar waves via a transmission antenna; a receiving circuit receiving the reflected waves via a receiving antenna; a delay line having an end connected to aid transmission circuit and the other end connected to said receiving circuit, which delays the radar waves by a predetermined delay amount; a correlation circuit/coherent detection circuit which detects a waveform having a strength equal to or higher than a predetermined strength, from a signal provided from said receiving circuit which obtains the signal from the reflected waves or the delayed radar waves; and a level decision circuit which judges, during self-diagnosis, whether or not the detected waveform is a waveform of the delayed radar wave according to the predetermined delay amount, and if the waveform is not the waveform of the delayed radar wave, determines that abnormality occurs in said radar system.

Growing community of inventors

Osaka, Japan

Noboru Negoro