Abstract: A power supply apparatus for a vehicle supplies/charges electric power to/from a power supply unit. The vehicle includes a first power-inverter circuit, a capacitor, high-resistance and low-resistance electric-paths between the capacitor and a battery, a first switching unit opening/closing the electric-paths, and a unit operating the first switching unit, when connecting between the battery and the first power-inverter circuit, in such a manner that after the high-resistance electric path is closed and the low-resistance electric path is opened, the high-resistance electric-path is opened and the low-resistance electric-path is closed.

Abstract: A power supply apparatus for a vehicle is provided which supplies electric power to a power supply unit and charges electric power from the power supply unit via a power port. The vehicle includes a plurality of power inverter circuits which are connected to a common storage unit in parallel. The plurality of power inverter circuits include an electric power transferring power inverter circuit connected to the power port via an electric power transferring electric path, and are divided into a first category including the electric power transferring power inverter circuit and a second category. The power supply apparatus includes a connection prohibiting unit which realizes a state in which the power inverter circuit included in the first category is electrically connected to the storage unit, and the power inverter circuit included in the second category is disconnected from the storage unit.

Abstract: A power supply apparatus for a vehicle is provided which supplies electric power to a power supply unit and charges electric power from the power supply unit via a power port. The vehicle includes a plurality of power inverter circuits which are connected to a common storage unit in parallel. The plurality of power inverter circuits include an electric power transferring power inverter circuit connected to the power port via an electric power transferring electric path, and are divided into a first category including the electric power transferring power inverter circuit and a second category. The power supply apparatus includes a connection prohibiting unit which realizes a state in which the power inverter circuit included in the first category is electrically connected to the storage unit, and the power inverter circuit included in the second category is disconnected from the storage unit.

Abstract: A power supply apparatus for a vehicle supplies/charges electric power to/from a power supply unit. The vehicle includes a first power-inverter circuit, a capacitor, high-resistance and low-resistance electric-paths between the capacitor and a battery, a first switching unit opening/closing the electric-paths, and a unit operating the first switching unit, when connecting between the battery and the first power-inverter circuit, in such a manner that after the high-resistance electric path is closed and the low-resistance electric path is opened, the high-resistance electric-path is opened and the low-resistance electric-path is closed.

Abstract: A power inverter for a polyphase load such as an AC motor is provided which is designed to minimize an on-off switching loss of transistors installed in the inverter. The inverter works to disenable switching operations of the transistors for each phase in a first cycle during which a corresponding output current is high in level and partially disenable the switching operations in a second cycle following the first cycle during which the corresponding output current is middle in level.

Abstract: A power inverter for a polyphase load such as an AC motor is provided which is designed to minimize an on-off switching loss of transistors installed in the inverter. The inverter works to disenable switching operations of the transistors for each phase in a first cycle during which a corresponding output current is high in level and partially disenable the switching operations in a second cycle following the first cycle during which the corresponding output current is middle in level.

Abstract: This invention provides a dynamical quantity sensor having a novel structure, wherein first beams 3, 4, 5, 6 are extended from side walls of a recess 2 of a substrate 1, and an intermediate support member 7 is disposed on the first beams 3, 4, 5, 6. Second beams 8, 9, 10, 11 extending in a direction crossing substantially perpendicularly the first beams 3, 4, 5, 6 are disposed on the intermediate support member 7, and a weight 12 is disposed on the second beams 8, 9, 10, 11. Opposing electrodes 17 and 19 and opposing electrodes 18 and 20 are used as electrodes for excitation, and opposing electrodes 13 and 15 and opposing electrodes 14 and 16 are used as electrodes for detecting an angular velocity. The movement of the weight 12 resulting from the application of the angular velocity is detected.

Abstract: A semiconductor device which improves heat radiation performance and realizes size reduction and enables heat to be radiated swiftly from both of the principal surfaces of a semiconductor chip even when the semiconductor chip has a construction vulnerable to stresses. It comprises several IGBT chips each having a collector electrode on one principal surface and an emitter electrode and a gate electrode on the other principal surface and two high thermal conductivity insulating substrates sandwiching these IGBT chips and having electrode patterns for bonding to the electrodes of the IGBT chips disposed on their sandwiching surfaces, the electrodes of the IGBT chips and the electrode patterns of the high thermal conductivity insulating substrates being bonded by brazing.

Abstract: This invention provides a dynamical quantity sensor having a novel structure, wherein first beams 3, 4, 5, 6 are extended from side walls of a recess 2 of a substrate 1, and an intermediate support member 7 is disposed on the first beams 3, 4, 5, 6. Second beams 8, 9, 10, 11 extending in a direction crossing substantially perpendicularly the first beams 3, 4, 5, 6 are disposed on the intermediate support member 7, and a weight 12 is disposed on the second beams 8, 9, 10, 11. Opposing electrodes 17 and 19 and opposing electrodes 18 and 20 are used as electrodes for excitation, and opposing electrodes 13 and 15 and opposing electrodes 14 and 16 are used as electrodes for detecting an angular velocity. The movement of the weight 12 resulting from the application of the angular velocity is detected.

Abstract: A resonant power converter includes a positive bus line (1A) and a negative bus line (1B). A power converting portion (2) connected between a DC power source (1) and a load (5) operates for implementing power conversion. The power converting portion includes a plurality of main switching devices (3a-3f) connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively for each phase. A resonant circuit (8) connected between the positive bus line and the negative bus line includes a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor. A control device (13) operates for switching the main switching devices in accordance with a predetermined pattern to enable the power converting portion to implement power conversion.

Abstract: A semiconductor device which improves heat radiation performance and realizes size reduction and enables heat to be radiated swiftly from both of the principal surfaces of a semiconductor chip even when the semiconductor chip has a construction vulnerable to stresses. It comprises several IGBT chips each having a collector electrode on one principal surface and an emitter electrode and a gate electrode on the other principal surface and two high thermal conductivity insulating substrates sandwiching these IGBT chips and having electrode patterns for bonding to the electrodes of the IGBT chips disposed on their sandwiching surfaces, the electrodes of the IGBT chips and the electrode patterns of the high thermal conductivity insulating substrates being bonded by brazing.

Abstract: A multi-level power converter such as an inverter for changing one of a plurality of dc voltage inputs into an ac voltage output is provided which includes inverter arms disposed between dc power supplies and an ac voltage output terminal. The inverter arms include switching circuits which are selectively subjected to PWM control to establish and block communication between one of the corresponding dc power supplies and the ac voltage output terminal. The switching circuits that are not connected to either the maximum or minimum dc voltage terminal include a first switching device, a second switching device connected in series with the first switching device, a first diode connected backward in parallel to the first switching device, and a second diode connected backward in parallel to the second switching device. This structure decreases the number of floating power supplies for driving the switching elements.

Abstract: A dynamic quantity sensor comprises a weight and plurality of L-shaped beams adapted to be anchored at first ends thereof. The weight is supported by second ends of the L-shaped beams. The L-shaped beams each have a predetermined surface thereof sharing a common plane. The weight is movable in two directions within a plane substantially parallel to the common plane in response to a change in dynamic force applied to the dynamic quantity sensor.

Abstract: There is provided a monolithic photocoupler which is easy to integrate. An SOI structure is formed by providing a first insulation layer on a silicon substrate. The semiconductor single crystal region is further divided by trench insulation layers into separate regions. Light emitting elements are formed on one of the separated semiconductor single crystal region and light receiving elements are formed on the other semiconductor single crystal region. The light emitting elements are obtained by forming light emitting diodes made of GaAs or the like on the substrate using a heterogeneous growth process. An optical waveguide made of a material which is optically transparent and electrically insulative such as a TiO.sub.2 film on each pair of light emitting and light receiving elements. The insulation layers constituted by SiO.sub.2 layers have a refractive index smaller that of the active layer of the substrate.

Abstract: A semiconductor device having superior light output efficiency is disclosed. A p-Si diffusion layer is formed on a Si substrate and an n-Si diffusion layer is formed in the p-Si diffusion layer. An n-GaAs layer constituting an active region for emitting light is grown on the p-Si diffusion layer and the n-Si diffusion layer of the Si substrate and a p-GaAs layer constituting an active region for emitting light is grown on the n-GaAs layer. An upper electrode is disposed on an upper surface of the p-GaAs layer above the p-Si diffusion layer. Current is injected from the upper electrode through a region of the pn junction between the n-GaAs layer and the p-GaAs layer other than that directly below the upper electrode, and light is emitted from this region. The emitted light passes through the p-GaAs layer to outside the device without passing through and being attenuated by the upper electrode.

Abstract: A semiconductor acceleration sensor including a trench provided in a main surface of a semiconductor substrate, the trench having a first inner wall, a second inner wall opposite to the first inner wall, and a third inner wall joining the first and second inner walls. A gate electrode faces the first, second and third inner walls of the trench through an air gap. A first semiconductor unit is formed in the first inner wall consisting of three adjoining semiconductor layers for detecting a displacement of the gate electrode relative to the first semiconductor unit induced by an applied acceleration, each of the three adjoining semiconductor layers in the first semiconductor unit having a different conductivity type.

Abstract: A thermal type flow rate sensor comprising a sensor chip having a rectangular shape. The sensor chip is supported between supporting pins through ribbon-like leads connected to opposite ends of the sensor chip. The ribbon-like leads serve to correctly locate the surface of the sensor chip with respect to flow of fluid. The surfaces of the sensor chip is formed with a thin film heater. A heater portion of the thin film heater comprises a plurality of straight portions and a plurality of turn portions connecting the straight portions to each other. Each turn portion is formed in a smoothly curved shape to avoid the concentration of electric currents and is disposed at an end portion of the sensor chip which has a comparatively low temperature. This structure is effective in preventing generation of cracks in the turn portions. In addition, the plurality of straight portions are alternatively inclined to effectively utilize the surface of the sensor chip to form a long heating portion.

Abstract: In an improved semiconductor pressure sensor adapted to detect a pressure of a measured medium such as a refrigerant used in a refrigerating cycle for an automobile, there are provided a sensing portion composed of a glass support plate and a silicon substrate disposed thereon and provided with a diaphragm portion displaceable in accordance to a pressure of the measured medium at such a position of the silicon substrate as to be brought into contact with the measured medium, a detecting means disposed within the sensing portion so as to detect a displacement of the diaphragm portion, a housing having an interior space including an accommodation portion for accommodating the sensing portion and having at least a predetermined portion of the accommodation portion made up of metal as opposed to the sensing portion, and a solder glass provided between the predetermined portion of the housing and a predetermined portion of the sensing portion so as to hermetically seal the interior space of the housing with respec

Abstract: A facedown-type semiconductor pressure sensor has a Si sensing element including a diaphragm, a spacer, and a piezoresistive device embedded in the diaphragm, and a pedestal. The spacer, which is positioned between the semiconductor substrate and the pedestal, has a photolitho-graphically etched hole such that the sensing element, the hole and the pedestal define a sealed chamber. The sealed pressure chamber is substantially aligned with the diaphragm.

Abstract: This invention provides a dynamical quantity sensor having a novel structure, wherein first beams 3, 4, 5, 6 are extended from side walls of a recess 2 of a substrate 1, and an intermediate support member 7 is disposed on the first beams 3, 4, 5, 6. Second beams 8, 9, 10, 11 extending in a direction crossing substantially perpendicularly the first beams 3, 4, 5, 6 are disposed on the intermediate support member 7, and a weight 12 is disposed on the second beams 8, 9, 10, 11. Opposing electrodes 17 and 19 and opposing electrodes 18 and 20 are used as electrodes for excitation, and opposing electrodes 13 and 15 and opposing electrodes 14 and 16 are used as electrodes for detecting an angular velocity. The movement of the weight 12 resulting from the application of the angular velocity is detected.