Fujitsu Corporation

Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Akira Yamamoto

Tatsuo Nagayoshi

Hideaki Sugiya

Koji Bato

Tomoyuki Sakata

Yuichiro Sakane

Katsumi Sugawa

Makoto Ohtou

Yoshikazu Tsunoda

Fumio Wada

Yuki Hata

Taro Asao

Hiromu Yoshii

Yasushi Sugaya

Hiroshi Tsuji

Noboru Miyamoto

Takuji Maeda

Toshinobu Banjo

Khalid Hassan Hussein

Masaharu Yoshida

Shintaro Araki

Takahiko Murakami

Masanori Kondoh

Masahiro Oohashi

Yoshinori Tochiki

Haruki Tanaka

Kouji Tanonaka

Akihiro Horiuchi

Satsuki Norimatsu

Kouichi Maeda

Tsutomu Tsurumi

Yuki Murakami

Ryuta Hoshi

Haruka Miyazaki

Takatoshi Yasui

Kousuke Nakamura

Tougo Fukushi

Nobuo Fukuda

Seiji Sugiyama

Mitsuru Shirai

An object is to provide a semiconductor device that can prevent increase in the package size and detect a current with high precision by suppressing a current induced by magnetic flux. A semiconductor deviceis connectable to a control boarddetecting a current flowing through an IGBTincluded in the semiconductor deviceand functioning as a semiconductor element. The semiconductor deviceincludes an insulating substrate, the IGBT, and a sense resistor. The IGBTis disposed on the insulating substrate, and includes a sense electrode and an emitter electrode. The sense resistoris disposed on the insulating substrate, and has one end connected to the sense electrode and the other end connected to the emitter electrode. The control boarddetects a potential difference between both ends of the sense resistorto detect the current flowing through the IGBT

Semiconductor device

A semiconductor apparatus includes a metal body in which a through hole is formed, a socket that covers the metal body without closing the through hole, a connection terminal connected to the metal body and exposed to an outside of the socket, a control board having a metal pattern and a circuit pattern, and a semiconductor chip having a control terminal connected to the circuit pattern via the through hole without being in contact with the metal body, the connection terminal being connected to the metal pattern.

Semiconductor apparatus

An object of the present invention is to synchronize PWM between individual phases of an IPM, so that the IPM has a simplified-scale circuit. An IPM according to the present invention includes a DC-DC converter including a multi-phase arm having a plurality of phase arms connected in parallel on a secondary side, a secondary-wire-voltage detection circuit configured to detect a secondary wire voltage in each phase arm of the DC-DC converter, and a synchronization-signal generation circuit configured to generate a synchronization signal in each phase arm on the basis of the behavior of the secondary wire voltage.

Intelligent power module

A voltage detecting circuit of the present invention is formed of a differential amplifier and an H-detection filter circuit, and the differential amplifier amplifies a potential difference between an input voltage and a primary-side voltage to obtain a differential amplified voltage. The H-detection filter circuit extracts low frequency components of the differential amplified voltage to output a detection voltage. A DC/DC control IC outputs, to a control electrode of a transistor, a PWM signal obtained by shaping a pulse width based on the detection voltage, to thereby control an on/off operation of the transistor.

Switching control circuit and switching power supply device

A gate circuit includes a gate resistive element connected at one end to the gate of a power device, an on-switching device connected between a power supply and the other end of the gate resistive element, a first resistive element whose connection to the gate is controlled by a first switching device, a second resistive element whose connection to the gate is controlled by a second switching device, and having a higher resistance value than the first resistive element, excessive current suppression means for turning on the first switching device just when the current in the power device reaches a predetermined value, and turn-off delay means for, after the excessive current suppression means turns on the first switching device, turning off the on-switching device and the first switching device and turning on the second switching device to turn off the power device.

Gate circuit

An optical transmission device that is installed at a node of a network and that performs transmission of an optical signal transmits the optical signal to an optical transmission device at the next node without amplifying the optical signal. The optical transmission device generates an adjustment optical signal used by a reception-side optical amplifier in the optical transmission device at the next node to adjust gain for a transmission loss of the optical signal. At the time of booting of the optical transmission device, the optical transmission device transmits the generated adjustment optical signal to the reception-side optical amplifier in the optical transmission device at the next node. Upon receiving a gain-adjustment-completion signal for notifying completion of gain adjustment using the adjustment optical signal from the reception-side optical amplifier, the optical transmission device controls the transmission of the adjustment optical signal to be stopped.

Optical transmission device, optical transmission method, and recording medium thereof

A temperature detection system includes a power semiconductor device, a chip temperature detection device for detecting a temperature of the power semiconductor device, loss-related characteristic value acquiring means for acquiring a loss-related characteristic value that is a characteristic to decide a loss of the power semiconductor device, difference value calculating means for calculating, from the loss-related characteristic value, a difference value between the temperature of the power semiconductor device and a temperature detected by the chip temperature detection device, a corrected temperature signal generating part for generating a corrected temperature signal by adding the temperature detected by the chip temperature detection device and the difference value, and an output part for outputting the corrected temperature signal to the outside.

Temperature detection system

An optical transmitter and receiver has stored in advance therein FEC techniques and applicable conditions for applying the FEC techniques to a counterpart optical transmitter and receiver. The optical transmitter and receiver measures a state of receiving data transmitted from the counterpart optical transmitter and receiver, determines an applicable condition satisfying the measured data reception state from among the stored applicable conditions, and selects a FEC technique stored in association with the applicable condition determined as satisfying. The optical transmitter and receiver then notifies the counterpart optical transmitter and receiver of the selected FEC technique.

Optical transmitter and receiver and optical transmission and reception system

An optical pickup which has a failure prediction apparatus for predicting a failure of a laser diode has an input inputting a value of a current that flows through the laser diode and is measured at predetermined time intervals, a storage storing the current values inputted by said input, a detector detecting a current value that is a current value at any one of the measurement times of day stored in said storage and that has a change greater than or equal to a predetermined value relative to the current value at the preceding measurement time of day, and a generator generating a prediction curve that indicates a relationship between said elapsed time and the current value applicable at and after the measurement time of day of the current value detected by said detector.

Failure prediction apparatus and failure prediction method

An aspect of the embodiments utilizes an optical transmission apparatus which includes a rough adjustment execution portion that monitors a bit error rate of an optical signal for set values of a dispersion compensator where the set values have been set less closely to each other within a dispersion compensation control range than when a wavelength dispersion value set in the dispersion compensator is determined, and carries out a rough adjustment to determine a comparison threshold value used to set the wavelength dispersion value based on the monitored bit error rate, and a fine adjustment execution portion that monitors the bit error rate for the dispersion compensator the set values have been set more closely to each other, and carries out an adjustment to determine a wavelength dispersion value corresponding to the midpoint between the two acquired bit error rates as the wavelength dispersion value of the dispersion compensator.

Optical transmission apparatus, optical transmission method, and optical transceiver

An optical wavelength multiplexing system includes transmission-side and reception-side optical wavelength multiplexers, and terminal devices, which are connected to each other by optical fiber cables. Optical wavelength converters in the transmission-side optical wavelength multiplexers are connected to ports respectively. The optical wavelength converter converts an input optical signal into an arbitrary preset wavelength to generate a converted optical signal. The port has a predetermined wavelength preset therein. Each optical power level of input converted optical signals is compared with each optical power level of optical signals of respective wavelengths set in the ports. When a difference is detected in the comparison result, it is determined that an optical wavelength converter is incorrectly connected to the port.

Optical wavelength multiplexing system, optical wavelength multiplexing method, and computer product

A measurement apparatus for measuring an optical fiber transmission line used to connect to an opposite apparatus, the measurement apparatus includes a transmission part for generating a measurement packet used for measuring a length of a first and second optical fiber transmission line, and transmitting the measurement packet to the opposite apparatus through the first optical fiber transmission line, a reception part for detecting the measurement packet returned from the opposite apparatus that perform a loopback processing of the measurement packet through the second optical fiber transmission line, a calculation part for calculating a packet transmission time which is a processing time required from the generation of the measurement packet to the detection of the measurement packet, and a measurement part for performing a measurement control of the length of the first and second optical fiber transmission line based on the packet transmission time calculated by the calculation part.

Optical fiber transmission line measurement apparatus and system

A wavelength-multiplexing optical transmission apparatus includes an optical-wavelength-information storing unit that stores optical wavelength information on an optical wavelength of an optical signal to be output from a transponder, and an optical-wavelength-information transmitting unit that transmits the stored optical wavelength information to the transponder via a connection cable. The transponder includes an optical-wavelength control unit that controls an optical wavelength of an optical signal to be input to a wavelength multiplexing unit based on the optical wavelength information received from the optical-wavelength-information transmitting unit.

Wavelength-multiplexing optical transmission system and wavelength-multiplexing optical transmission method

An identification apparatus for identifying an optical passive device product. The apparatus includes an optical input output monitor section for monitoring an optical input and an optical output of the optical passive device product respectively; a loss calculation section for calculating a loss in the optical passive device product based on a monitoring result of the optical input output monitor section; and a product identification section in which product information indicating a correspondence between a loss characteristic and a product has been stored in advance, and which identifies the optical passive device product by comparing the stored product information and the loss calculated by the loss calculation section.

Optical passive device product identification apparatus and connectivity determination apparatus

The present invention provides an optical add/drop multiplexer including an optical power control unit for performing a control of an optical power by the unit of each signal light included in the wavelength multiplexed light, wherein the optical power control unit includes control logic for implementing a first control mode in which a transition to an automatic control of the optical power and release from the aforementioned control are carried out by comparing the optical power with a threshold value, and a second control mode in which a transition to an automatic control of the optical power is carried out based on control information of a notification by another of the optical add/drop multiplexers and release from the automatic control is carried out based on the comparison between the optical power and the threshold value.

Growing community of inventors

Fukuoka, Japan

Akira Yamamoto