Sanken Electric Co., Ltd.

Shimane University

Honda Motor Co., Ltd.

Masaki Kanazawa

Hideki Asuke

Hironobu Sou

Hideki Nakamichi

Mamoru Tsuruya

Nanjou Aoike

Hideharu Takano

Masayoshi Yamamoto

Shigeyuki Funabiki

Akio Iwabuchi

Toshiaki Ariyoshi

Katsuyuki Torii

Takafumi Tsurumi

Kiyokatsu Satoh

Kazuya Aizawa

Yoshikazu Nomoto

Hirotaka Hara

Norimasa Yamada

Hiroyuki Horii

A semiconductor device () includes: an base substance () having a ferromagnetic material; a first semiconductor chip () and a second semiconductor chip () installed on the base substance (); a first coil () installed on the base substance () and electrically connected to the first semiconductor chip (); a second coil () installed on the first coil (), electromagnetically connected to the first coil () and electrically connected to the second semiconductor chip (); a transformer assembly () made of a ferromagnetic material and installed on the base substance (), and a sealing body. The transformer assembly () includes a first core section (), a first side shield section (), and a first upper shield section ().

Semiconductor device

A current-mode controlled DC-DC converter includes a comparator comparing a first or second current detection signal with a first or second reference current that is based on an error voltage of a voltage detection signal, a pulse generator generating a first pulse signal whose ON time is longer than an interval between when the second current detection signal reaches a minimum value and when the second current detection signal reaches the second reference current, a pulse generator generating a second pulse signal whose ON time is longer than an interval between when the first current detection signal reaches a minimum value and when the first current detection signal reaches the first reference current, the second pulse signal being behind the first pulse signal by a half period, and a PWM circuit generating a first or second PWM signal according to the pulse signal and an output signal from the comparator, thereby turning on/off a switch.

Current-mode controlled DC-DC converter

A semiconductor deviceincludes a first transistorplaced on a substrate, a second transistorplaced on the first transistorvia a heat radiation layer, a third transistorplaced on the substrate, and a fourth transistorplaced on the third transistorvia a heat radiation layer. The first transistorhas a first region corresponding to a region where the second transistor is placed, and a second region which is formed so as to surround the first region and in which the rate of area occupied by the emitter region in the base region is higher than in the first region. Likewise the first transistor, the third transistorhas a region in which the rate of area occupied by the emitter region in the base region is varied.

Semiconductor device having plural regions and elements with varying areas depending on the region

A bi-directional DC-DC converter includes a first series circuit connected to ends of a first DC power source and including a first winding of a first reactor and a first switch; a second series circuit connected to ends of the first switch and including a second winding of the first reactor, a second reactor, a second switch, a third switch, and a second DC power source; a third series circuit connected to the ends of the first switch and including a fourth switch and the second DC power source; and a control circuit configured to turn on/off the switches and thereby carry out step-up and step-down operations between the first and second DC power sources.

Bi-directional DC-DC converter

A semiconductor device is provided which comprises a heat-radiative support plate; and first and second semiconductor elementsandmounted and layered on support platefor alternate switching of first and second semiconductor elementsand. The arrangement of piling and securing first and second semiconductor elementsandon support plateimproves integration degree of semiconductor elementsand, and reduces the occupation area on support plate. Alternate switching of first and second semiconductor elementsandcontrols heat produced from first and second semiconductor elementsandbecause one of first and second semiconductor elementsandis turned on, while the other is turned off.

A solenoid drive circuit includes a control circuit which comprises a detector with a resistor for discerning current flow therethrough to produce electric signals that correspond to level of current flow through a solenoid connected to the resistor; an amplifier for amplifying the electric signals from the resistor; and an integrator for integrating the amplified output from the amplifier.

Solenoid drive circuit

A voltage measurement device includes a first group of switches Q, Q, a second group of switches Q, Qand a third groups of switches Q, Q. By turning on the third group of switches Q, Q, the first group of switches Q, Qare turned on, so that a condenser Cis charged by voltage impressed between a voltage input terminal A and a voltage input terminal B. While the first group of switches Q, Qare turned off by tuning off the third group of switches Q, Q, the second group of switches Q, Qare turned on, so that voltage retained in the condenser Cis generated between a voltage output terminal G and a voltage output terminal H.

Voltage measurement device

For packaging an electric circuit of the kind having a coil or coils in addition to electronic components such as transistors, diodes, and capacitors, a plastic molding is provided which comprises a bobbin with a pair of flanges on its opposite ends. The coils are wound on the bobbin and retained in position thereon by the flanges. The electronic components of the circuit, such as transistors and diodes, are all integrally embedded in one of the flanges and electrically connected to sheet-metal terminals which also are partly embedded in the same flange.

Packaging of an electric circuit including one or more coils

A lighting system for a fluorescent lamp includes an inverter circuit having a pair of outputs between which is connected a resonant circuit of an inductor and a capacitor in series, with the discharge lamp connected in parallel with the capacitor. An inversely frequency dependent voltage is applied between the lamp electrodes according to a predefined resonance characteristic. During a preheat period, which precedes a lightup period during which the lamp is to be lit up with the commencement of an electric discharge between the lamp electrodes, the voltage is made lower in the first half than in the second, thereby averting the sudden flow of a large preheating current through the filamentary lamp electrodes.

Incrementally preheating and lighting system for a discharge lamp

A lighting system for a fluorescent lamp includes an inverter circuit to which is connected a load circuit including a resonant circuit of an inductor and a capacitor in serial connection, with a lamp connected in parallel with the capacitor. An inversely frequency dependent voltage is applied between the lamp electrodes according to a predefined resonance characteristic such that the resonance frequency is less than a discharge start frequency at which the lamp is to start glowing. For lighting up the lamp the frequency of the inverter output voltage is changed from a first frequency that is higher than the discharge start frequency to a second frequency that is less than the resonance frequency. If the lamp accidentally goes off, the current flowing through the load circuit will advance out of phase with the inverter output voltage, possibly resulting in the destruction of the inverter switch or switches due to overcurrent. This danger is precluded by constantly monitoring the phase of the load current and, in event the load current is found to be in phase advance, by making the inverter output frequency higher than the resonance frequency of the resonant circuit and thereby delaying the phase of the load current.

Growing community of inventors

Niiza, Japan

Masaki Kanazawa