63results about How to "Switching loss increase" patented technology

The invention is intended to provide a control device for a vehicular AC motor, which has higher efficiency of voltage utilization in a power running mode and has higher efficiency of electricity generation in an electricity generation mode. The motor control device comprises rectifying devices and switching devices for three phases, which are connected between a DC power source and armature coils of an AC motor operatively coupled to an internal combustion engine. The motor control device has the inverter function of converting a DC power from the DC power source into an AC power and supplying the AC power to the armature coils, and the converter function of converting an AC power generated by the AC motor into a DC power and supplying the DC power to the DC power source. Rectangular-wave driving control of applying rectangular wave voltages to the armature coils of the AC motor is performed when the AC motor is operated for power running, and synchronous rectification control for making synchronous rectification of the AC power generated by the AC motor is performed when the AC motor is operated for electricity generation.

A power semiconductor device comprising a base, a trench, a heavily doped polysilicon structure, a polysilicon gate, a gate dielectric layer, and a heavily doped region is provided. The trench is formed in the base. The heavily doped polysilicon structure is formed in the lower portion of the trench. At least a side surface of the heavily doped polysilicon structure touches the naked base. The polysilicon gate is located in the upper portion of the trench. The gate dielectric layer is interposed between the polysilicon gate and the heavily doped polysilicon structure. The dopants in the heavily doped polysilicon structure are diffused outward to form a heavily doped region.

A power factor correction circuit includes; a series circuit connected to a positive-electrode output terminal P1 and negative-electrode output terminal P2 of a full-wave rectifying circuit B1, which rectifies an having current power-supply voltage of an alternating current power-supply Vac1, and including a booster winding 5a and a wind-up winding 5b wound on a booster reactor L1, a diode D1 and a smoothing capacitor C1; a series circuit, connected between the positive-electrode output terminal P1 and the negative-electrode output terminal P2 and having the booster winding 5a, a ZCS reactor L2 and a switch Q1; a diode D2 connected between a junction, between the switch Q1 and the ZCS reactor L2, and the smoothing capacitor C1; and a control circuit 10 that controllably turns the switch Q1 on and off for controlling an output voltage of the smoothing capacitor C1 to a given voltage.

An IGBT module is configured with a plurality of IGBT cells connected to each other. The IGBT chips are each configured a plurality of unit cells connected to each other. The unit cells each include one IGBT element. Gate voltage is applied to the gate of the IGBT element from a common gate terminal through a gate pad and a gate resistor. Emitter voltage is applied to the emitter of the IGBT element from a common emitter terminal through an emitter pad. Collector voltage is applied to the collector of the IGBT element from a common collector terminal. The gate pad, gate transistor and emitter pad are provided for each of the unit cells. Thus obtained is an IGBT module capable of suppressing gate voltage oscillation without significantly increasing switching loss.

An electronic ballast includes circuitry to prevent a switch from being damaged in the case where an abnormality occurs in an output voltage of an input power supply. A DC power supply control circuit has a zero current detection circuit that, when a current through an inductor becomes equal to or less than a predetermined current value, outputs a zero signal. A peak current detection circuit, when current through a switch the DC power supply circuit becomes equal to or greater than the predetermined current value, outputs a peak signal. A first drive circuit turns on the switch according to the zero signal, and turns off the switch Q1 according to the peak signal. The zero current detection circuit is provided with a mask circuit that stops the zero signal from being outputted to the first drive circuit for a predetermined period after the current through the inductor has become equal to or less than the predetermined current value.

A power converter enhances conversion efficiency from DC power to AC power. A first chopper circuit chops DC voltage from a photovoltaic panel at a system frequency producing a first square-wave whose voltage level changes positively. A second chopper circuit chops the first square-wave at a frequency double the system frequency producing a second square-wave whose voltage level changes negatively and adds the first square-wave and the second square-wave to produce a third square-wave that changes positively and negatively in a sine-wave manner. A third chopper circuit charges and discharges by chopping the third square-wave at a third frequency fixed by timing according to a difference between the third square-wave and a sine-wave voltage. PWM control is performed on the charge and discharge outputs such that the difference is corrected, producing a sine-wave voltage that continuously changes positively and negatively. A spike noise of an output voltage is suppressed.

Lighting apparatus which supplies a current to solid-state light-emitting device (LED) includes: DC power supply circuit (AC/DC converter); and DC/DC converter that converts an output voltage of DC power supply circuit and applies, to solid-state light-emitting device, the output voltage converted. DC/DC converter includes: switching element; and DC/DC control circuit that performs a control of repeatedly turning ON and OFF switching element in a boundary conduction mode, and DC power supply circuit adjusts the output voltage to make a switching frequency of switching element higher than a first frequency, based on a forward voltage to be applied to solid-state light-emitting device.

Routing of a gate signal for controlling a discrete power switching device (such as in an inverter for an electric vehicle drive) is configured to compensate for the common source inductance inherent in the switching device as a result of its integrated circuit packaging. The power device has a gate signal path via a gate pin and a power signal path via first and second power pins, wherein the gate signal path and the power signal path have a first mutual inductance. A circuit board apparatus provides a gate wiring loop juxtaposed with the power signal path, wherein the gate wiring loop and the power signal path have a second mutual inductance substantially canceling the first mutual inductance. The resulting reduction in common source inductance avoids the reductions in switching speed and the increased switching losses otherwise introduced by the common source inductance.

A control circuit for controlling an electronic circuit, which has a current path through a semiconductor switch and a line; when the semiconductor switch is switched, the inductance of the line and/or of a component in the current path producing an excess voltage between a first and a second current-carrying terminal of the semiconductor switch; the control circuit having a controllable current source for charging or discharging a charge-controlled gate of the semiconductor switch with the aid of a control current, as well as a control unit; the control unit controlling the current source in such a manner, that in the case of a switching operation, the terminal voltage across the current-carrying terminals of the semiconductor switch does not exceed a predefined setpoint terminal voltage.

A signal coding technique for switching amplifiers includes quantizing the amplitude A(t) of an input signal to produce a time series Â(t) having M levels; modulating a clock signal in response to Â(t), thereby to produce a control signal; switching among at least three different power supply output levels in response to the control signal, thereby to generate an output pulse stream; and filtering the output pulse stream to produce an output signal for transmission.

A SGT MOSFET having ESD diode and a method of manufacturing the same are disclosed. The SGT trench MOSFET according to the present invention, has n+ doped shielded electrode in an N channel device and requires only two poly-silicon layers, making the device can be shrunk with reducing shielded gate width for Rds reduction without increasing switching loss and having dynamic switching.

In a semiconductor device, a plurality of semiconductor chips included in an upper-arm circuit are connected in parallel between a pair of upper-arm plates, while a plurality of semiconductor chips included in a lower-arm circuit are connected in parallel between a pair of lower-arm plates. In each of the arm circuits, the plurality of semiconductor chips are arranged in a direction perpendicular to a direction in which emitter electrodes and pads are arranged, the pads are disposed on the same side of the emitter electrodes, and signal terminals extend in the same direction. A series-connecting part between the upper- and lower-arm circuits includes a joint part 20 continued to respective side surfaces of the corresponding upper- and lower-arm plates. Each of inductances of respective parallel-connecting parts of the upper- and lower-arm plates which connect the semiconductor chips in parallel is smaller than an inductance of the series-connecting part.