995 results about "Flyback diode" patented technology

A semiconductor switch is provided with a main element having reverse conductivity and serving as a voltage-driven switching element having a high withstand voltage, an auxiliary element serving as a voltage-driven switching element having a withstand voltage lower than that of the main element, and a high-speed freewheel diode having a withstand voltage equal to that of the main element, wherein a negative pole of the main element is connected to a negative pole of the auxiliary element to define the positive pole of the main element as a positive pole terminal and the positive pole of the auxiliary element as a negative pole terminal, and the high-speed freewheel diode is parallel-connected between the positive pole terminal and the negative pole terminal so that a direction from the negative pole terminal toward the positive pole terminal constitutes a forward direction.

A ripple converter includes a transistor for switching an input direct-current voltage, a choke coil and a smoothing capacitor for smoothing the switched direct-current voltage, a flywheel diode for causing a current to flow through the choke coil when the transistor is turned off, and a comparing unit for controlling the ON / OFF of the transistor according to ripple in an output voltage. In the ripple converter, a waveform converter is provided on a connecting path between an output terminal and a non-inverting input terminal of a comparator in the comparing unit. A result of converting the waveform of the output voltage is compared with a reference voltage, and a result of the comparison is fed back to the transistor.

A power converter having two main switches connecting an outlet either to a positive rail or to a negative rail, two free-wheel diodes enabling the current through the load to be maintained, two snubber capacitors, and an auxiliary circuit. The auxiliary circuit includes an auxiliary inductor in series with two auxiliary switches coupled between the outlet and a midpoint of a capacitive voltage divider that provides a midpoint voltage. A detector detects current oscillation between the auxiliary inductor and the snubber capacitors, and then switches off the oscillation current and allows the intended main switch to conduct in response to the interruption.

A DC / DC converter that is small, light, highly efficient, and inexpensive are provided which includes a DC power supply input section, a first and second capacitor connected in series, and an output section connected to the series connected first and second capacitors, a switching device that switches a plurality of switches which incorporate a configuration for connecting a power supply of the DC power supply input section, to the first capacitor and the second capacitor, and a switching control device that controls ON / OFF switching of the respective switches in the switching device in accordance with an operation mode.

A reverse-conducting semiconductor device is disclosed with an electrically active region, which includes a freewheeling diode and an insulated gate bipolar transistor on a common wafer. Part of the wafer forms a base layer with a base layer thickness. A first layer of a first conductivity type with at least one first region and a second layer of a second conductivity type with at least one second and third region are alternately arranged on the collector side. Each region has a region area with a region width surrounded by a region border. The RC-IGBT can be configured such that the following exemplary geometrical rules are fulfilled: each third region area is an area, in which any two first regions have a distance bigger (i.e., larger) than two times the base layer thickness; the at least one second region is that part of the second layer, which is not the at least one third region; the at least one third region is arranged in the central part of the active region in such a way that there is a minimum distance between the third region border to the active region border of at least once the base layer thickness; the sum of the areas of the at least one third region is between 10 and 30% of the active region; and each first region width is smaller than the base layer thickness.