Abstract: A power conversion circuit includes a high side switching device connected at its collector to the high potential side of a power supply, a low side switching device connected at its emitter to the low potential side of the power supply, a first junction to which the emitter of the high side switching device and the collector of the low side switching device are connected, a first diode connected at its cathode to the collector of the high side switching device, a second diode connected at its anode to the emitter of the low side switching device, a second junction to which the anode of the first diode and the cathode of the second diode are connected, an inductance connected between the first and second junctions, and a snubber circuit connected to the first junction and adapted to absorb stored energy in the inductance when a freewheeling current flows.

Abstract: An inverter device, a motor driving device, a refrigerating air conditioner, and a power generation system, which can reduce the recovery loss thereof, are obtained. A plurality of arms that can conduct and block current are provided. At least one of the plurality of arms includes: a plurality of switching elements each having a parasitic diode and being connected in series with each other; and a reverse current diode connected in parallel with the plurality of switching elements.

Abstract: A power conversion circuit includes a high side switching device connected at its collector to the high potential side of a power supply, a low side switching device connected at its emitter to the lowpotential side of the power supply, a first junction to which the emitter of the high side switching device and the collector of the low side switching device are connected, a first diode connected at its cathode to the collector of the high side switching device, a second diode connected at its anode to the emitter of the low side switching device, a second junction to which the anode of the first diode and the cathode of the second diode are connected, an inductance connected between the first and second junctions, and a snubber circuit connected to the first junction and adapted to absorb stored energy in the inductance when a freewheeling current flows.

Abstract: A power conversion circuit which receives a high potential, a low potential, and a neutral potential intermediate between the high and low potentials includes an AC switch connected so as to receive the neutral potential and a switching device receiving the high potential. The AC switch includes a diode and an inductance is connected to the diode and the switching device.

Abstract: An inverter device, a motor driving device, a refrigerating air conditioner, and a power generation system, which can reduce the recovery loss thereof, are obtained. A plurality of arms that can conduct and block current are provided. At least one of the plurality of arms includes: a plurality of switching elements each having a parasitic diode and being connected in series with each other; and a reverse current diode connected in parallel with the plurality of switching elements.

Abstract: A semiconductor switching device includes a power control part, which includes a voltage dropping chopper circuit having a first switching element and a first diode, a voltage boosting chopper circuit having a second switching element and a second diode, and an inductance. And the inductance is connected such that an unusual current caused by the arm short circuit is forced to pass through the inductance.

Abstract: An inverter device, a motor driving device, a refrigerating air conditioner, and a power generation system, which can reduce the recovery loss thereof, are obtained. A plurality of arms that can conduct and block current are provided. At least one of the plurality of arms includes: a plurality of switching elements each having a parasitic diode and being connected in series with each other; and a reverse current diode connected in parallel with the plurality of switching elements.

Abstract: A power conversion circuit includes a high side switching device connected at its collector to the high potential side of a power supply, a low side switching device connected at its emitter to the low potential side of the power supply, a first junction to which the emitter of the high side switching device and the collector of the low side switching device are connected, a first diode connected at its cathode to the collector of the high side switching device, a second diode connected at its anode to the emitter of the low side switching device, a second junction to which the anode of the first diode and the cathode of the second diode are connected, an inductance connected between the first and second junctions, and a snubber circuit connected to the first junction and adapted to absorb stored energy in the inductance when a freewheeling current flows.

Abstract: A semiconductor switching device includes a power control part, which includes a voltage dropping chopper circuit having a first switching element and a first diode, a voltage boosting chopper circuit having a second switching element and a second diode, and an inductance. And the inductance is connected such that an unusual current caused by the arm short circuit is forced to pass through the inductance.

Abstract: An insulated gate bipolar transistor, a semiconductor device using such a transistor, and manufacturing methods of these. The transistor, device, and method eliminate the necessity of connection to a freewheel diode used for bypassing a circulating current. In the transistor, device, and method the concentration of impurities of an N+ buffer layer that forms a junction with a P+ collector layer is increased so that it is possible to reduce an avalanche breakdown voltage of a parasitic diode formed by an N base layer and the P+ collector layer. Thus, the reverse voltage resistance of an IGBT is lowered to not more than 5 times the collector-emitter saturated voltage.

Abstract: It is an object to provide a semiconductor device comprising a short circuit protecting system capable of enhancing the detection precision of a collector current, thereby carrying out a reliable short circuit protection. An IGBT (1) having a collector (C) connected to a terminal (T1) and an emitter (E) connected to a terminal (T2) is provided, and has a sense emitter (SE) connected to a terminal (T2) through a variable resistor (VR1) to be a current and voltage converting section. A sense potential is output from an end on the sense emitter (SE) side of the variable resistor (VR1) and is given to a terminal (T11) of a current ratio detecting section (15). A gate of the IGBT (1) is connected to a terminal (T3) and an output of the current ratio detecting section (15) is connected to a terminal (T4).

Abstract: This invention relates to an insulated gate bipolar transistor, a semiconductor device using such a transistor and manufacturing methods of these, and in particular, its object is to eliminate the necessity of connection to a freewheel diode used for bypassing a circulating current.

Abstract: It is an object to provide a semiconductor device comprising a short circuit protecting system capable of enhancing the detection precision of a collector current, thereby carrying out a reliable short circuit protection. An IGBT (1) having a collector (C) connected to a terminal (T1) and an emitter (E) connected to a terminal (T2) is provided, and has a sense emitter (SE) connected to a terminal (T2) through a variable resistor (VR1) to be a current and voltage converting section. A sense potential is output from an end on the sense emitter (SE) side of the variable resistor (VR1) and is given to a terminal (T11) of a current ratio detecting section (15). A gate of the IGBT (1) is connected to a terminal (T3) and an output of the current ratio detecting section (15) is connected to a terminal (T4).

Abstract: In order to prevent a malfunction caused by an electrical noise and limit an excessive main current at a high speed while cutting off the same to a value close to zero, the main current is regulated by an IGBT (1) which is connected with a load. A part of this main current is shunted to another IGBT (2). The as-shunted current flows through a resistor (3), to be converted to a voltage across the resistor (3). When the main current is excessively increased by shorting of the load or the like, this voltage exceeds a prescribed value so that a transistor (5) and a thyristor (7) enter conducting states. Consequently, a voltage across a gate (G) and an emitter (E) of the IGBT (1) is so reduced as to cut off the main current. The transistor (5) prevents the main current from excessive increase since the same has a high speed of response, while the thyristor (7) cuts off the main current to zero since the same has lower resistance in conduction.