Abstract: Achieved is a load drive device capable of suppressing local concentration of temperature at the time of absorbing a counter electromotive force of an inductive load while suppressing a size of a power transistor. The load drive device includes a first transistor connected between a first control electrode and an inductive load. Further, the load drive device includes an active clamp circuit that becomes conductive when a terminal voltage of a second control electrode between the first transistor and the inductive load exceeds a threshold. Furthermore, the load drive device includes a second transistor connected to the second control electrode and connected in parallel to the first transistor.

Abstract: A power supply circuit is configured to convert a voltage of a second electricity storage element into a power supply voltage for a driving circuit, and a voltage detector is configured to detect the voltage of the second electricity storage element. A unit converter includes a first resistor connected to the second electricity storage element electrically in series between the terminals of a first electricity storage element, and a second resistor and a first switch connected electrically in series between the terminals of the second electricity storage element. The power supply circuit is configured to generate a control signal for controlling the first switch on and off based on the detection value from the voltage detector. The power supply circuit is further configured to sense an overloaded state of the second resistor based on the control signal.

Abstract: The present disclosure relates to a high electric power density bidirectional isolated low voltage DC-DC converter (LDC) assembly, in which a large-capacity bidirectional isolated LDC circuit is packaged in consideration of a flow of electric power so as to use components in common and minimize an internal dead space, and a cooling structure thereof. LDC assembly includes a power board subassembly (100) including the high voltage stage, a part of the buck circuit, and the boost circuit; a transformer subassembly (200) including a transformer of the buck circuit; an output power board subassembly (300) including a part of the buck circuit; and an EMC filter subassembly (400) including an EMC filter included in the low voltage stage.

Abstract: Various embodiments include an apparatus for limiting voltage for a DC voltage network, wherein overvoltages resulting from switching operations occur between a first supply potential level and a second supply potential level of the DC voltage network. The apparatus comprises at least two limiter cells connected in series between the first supply potential level and the second supply potential level. Each limiter cell comprises a controllable switching element, a discharge resistor, and a capacitor, across all of which a voltage applied between the first supply potential level and the second supply potential level is dropped. During operation of the apparatus, based at least in part on the voltage dropped across the respective capacitor of a particular limiter cell, the controllable switching element of the limiter cell is switched on or off.

Abstract: A semiconductor device that includes a semiconductor substrate having a first main surface and a second main surface, a first electrode opposing the first main surface of the semiconductor substrate, a dielectric layer between the semiconductor substrate and the first electrode, a first resistance control layer on the first electrode, a wiring part on the first resistance control layer, and a second electrode opposing the second main surface of the semiconductor substrate. The first resistance control layer includes a first region that has a first electrical resistivity and that electrically connects the first electrode and the wiring part, and a second region that is aligned with the first region and has a second electrical resistivity higher than the first electrical resistivity of the first region.

Abstract: In an electrical circuit arrangement, which is formed by an RC-snubber element monolithically integrated into a semiconductor substrate, a first capacitor and a resistor of the RC-snubber element are vertically formed in a semiconductor region of a first type of doping of the semiconductor substrate. At least one further capacitor is connected in series with the first capacitor. The further capacitor is integrated laterally with the first capacitor in a semiconductor region of a second type of doping, which adjoins the semiconductor region of the first type of doping, and by virtue of the different type of doping electrically insulates the further capacitor from the semiconductor region of the first type of doping. This circuit arrangement forms a low inductance RC-snubber element with high dielectric strength, which has high heat dissipation and integration density.

Abstract: According to some aspects of the present disclosure, power modules having current sensing circuits, and corresponding sensing methods, are disclosed. Example power modules include a printed circuit board (PCB) having a PCB trace, an output choke inductor, and an output pin. The power module also includes a first sense terminal coupled to the PCB trace, a second sense terminal coupled to the output pin such that a resistance between the first sense terminal and the second sense terminal is defined by a resistance of the PCB trace and a resistance of the output pin, and a control coupled to the first sense terminal and the second sense terminal. The control is adapted to measure a voltage between the sense terminals, and to determine a current through the PCB trace and the output pin based on the measured voltage and the resistance between the sense terminals.

Abstract: An electronic apparatus includes a first terminal that receives power supplied from an external apparatus, a second terminal that is used to determine a power supply capability of an external apparatus, an internal circuit that includes a communication control unit that communicates with an external apparatus via the second terminal, a capacitor that forms an AC coupling between the internal circuit and the second terminal, a route that bypasses the capacitor, a switch that causes the route to switch to a conductive state or a non-conductive state, and a control unit that controls the switch by determining whether a first voltage applied to the first terminal by the external apparatus exceeds a second voltage which can be applied to the internal circuit via the second terminal.

Abstract: A resonant power converter includes an event generator and multiple separate resonant tanks configured as second harmonic filters. The event generator is configured to generate a predetermined resonant switching frequency to which the resonant tanks are tuned, to selectively apply voltage stress harmonic links using the resonant tanks, and to control zero voltage switching time and peak current through the switching devices. Configuring and operating the resonant power converter in the manner described herein enables the resonant power converter to maintain a substantially constant efficiency over varying input line voltage, making the efficiency of the resonant power converter substantially independent of the input line voltage value.

Abstract: An electrostatic discharge (ESD) protection circuit for protecting one or more devices in an electronic circuit from an ESD current which enters the electronic circuit through one or more input/output pins, the protection circuit comprising: a voltage clamp circuit connectable to the or each pin, for diverting the ESD current from the or each device; and a current sensor circuit connected between the input/output pins and the voltage clamp circuit and connected to the one or more devices, the current sensor circuit for sensing the ESD current and for switching off the or each device when the sensed current exceeds a threshold value, wherein when a current flows in the current mirror circuits above a threshold value the device is caused to switch off.

Abstract: A protective circuit includes a first jack, a second jack, a first control unit, a detecting circuit, and a logic control circuit. The first jack is connected to a power supply, and includes a grounding wire and a live wire. The second jack is connected to a load, and includes a grounding wire and a live wire. The first control unit includes a first relay, the first relay is connected to the live wire of the first jack and the live wire of the second jack. The detecting circuit detects whether the grounding wire of the first jack is grounded, and outputs indication signals accordingly. The logic control circuit outputs a control signal to the first control unit according to the indication signals to turn on/off the first relay, for allowing the live wire of the first jack to be connected to/disconnected from the live wire of the second jack.

Abstract: A protection circuit for a power transistor includes a first transistor connected in parallel with the power transistor and having a control terminal connected to a first power supply voltage through a first resistive element; and a first set of diodes connected between a first terminal and a control terminal of the first transistor. In operation, the voltage at the first terminal of the first transistor is clamped to a clamp voltage and the first transistor is turned on to conduct current in a forward conduction mode when an over-voltage condition occurs at a first terminal of the power transistor.

Abstract: A system and method for efficient input/output (I/O) port overvoltage protection of a high-speed port. An interfacing system for connecting peripheral devices to a computing system comprises ports for conveying serial communications bi-directional signals and an overvoltage protection circuit. The protection circuit prevents an overvoltage condition on one port in response to an overvoltage event on a corresponding second port. In one embodiment, the interfacing system connects USB peripheral devices to an automotive infotainment system comprising an automotive battery potiential greater than a USB power supply. In addition, the overvoltage protection circuit is able to transmit signals between the two ports without signal attenuation defined by an industry standard specification such as Universal Serial Bus (USB) Implementers Forum (IF) eye pattern diagram test.

Abstract: A snubber circuit includes a capacitor and a buffer device. The buffer device has a first terminal and a second terminal. The first terminal is electrically connected to the capacitor. When the buffer device operates in a first conduction mode, a charge current flows from the second terminal to the first terminal through the buffer device. When the buffer device switches from the first conduction mode to a second conduction mode, the buffer device generates a discharge current which flows from the first terminal to the second terminal through the buffer device over a specific period of time, such that after the buffer device enters the second conduction mode, a relative maximum voltage level appearing first at the second terminal is lower than a voltage level at the first terminal.

Abstract: A high voltage semiconductor switch includes a first field-effect transistor having a source, a drain and a gate, and being adapted for switching a voltage at a rated high-voltage level, the first field-effect transistor being a normally-off enhancement-mode transistor, a second field-effect transistor having a source, a drain and a gate, connected in series to the first field-effect transistor, the second field-effect transistor being a normally-on depletion-mode transistor; and a control unit connected to the drain of the first field-effect transistor and to the gate of the second field-effect transistor and being operable for blocking the second field-effect transistor if a drain-source voltage across the first field-effect transistor exceeds the rated high-voltage level.

Abstract: The present invention discloses a lossless snubber circuit and an operation method thereof. The lossless snubber circuit includes a first snubber circuit. The first snubber circuit includes a first diode (D7) and a capacitor (C3). The capacitance of the capacitor (C3) is big enough so that a voltage spike generated at the moment when a switch transistor (Q1) is turned off is depressed by charging the capacitor (C3). When the switch transistor (Q1) is on, the electric charges released by the capacitor (C3) are directed to a first capacitor (C1) in a three-phase Vienna structure, so as to avoid the problem of voltage stress difference caused by the large quantity of electric charges released by the capacitor (C3) flowing back to the switch transistor (Q1).

Abstract: A mixed-voltage circuit employs a higher-voltage transistor in series connection with a lower-voltage transistor. To protect the lower-voltage transistor from transient overvoltage events, a series of one or more diodes is connected between the current terminals (i.e., the source and drain terminals) of the lower-voltage transistor so as to limit the voltage across the lower-voltage transistor. This diode protection mechanism also may be provided between the gate terminal and a current terminal of the lower-voltage transistor so as to protect against an overvoltage event at the gate of the lower-voltage transistor. In this manner, the mixed-voltage circuit can provide the performance benefits of mixed use of lower-voltage and higher-voltage transistors while reducing the risk of damaging the lower-voltage transistors due to the use of the higher-voltage power supply needed for operation of the mixed-voltage circuit.

Abstract: A fault protector for an opto-electronic device includes a MOSFET having an integral body-diode. A capacitor is connected between a drain and a gate of the MOSFET, and a resistor is connected between the gate and a source of the MOSFET. The drain of the MOSFET is connectable to a first terminal of an opto-electronic device, and the source of the MOSFET is connectable to a second terminal of the opto-electronic device. The device overcomes problems of previously known techniques by preventing a reverse-bias voltage from exceeding an absolute maximum specified by a manufacturer, and also prevents ESD or other power-related faults from exceeding the maximum forward-bias voltage of the laser diode, while not adding significant resistance or capacitance to the laser diode, thereby not complicating the task of driving the laser diode.

Abstract: A high voltage direct current (HVDC) hybrid circuit breaker is provided. The circuit breaker includes a solid-state main breaker, a mechanical fast disconnector and a solid-state auxiliary breaker connected in series, the series-connection of the disconnector and the auxiliary breaker being connected in parallel to the main breaker, a snubber circuit including a capacitor, and a switching device being arranged for disconnecting the snubber capacitor in response to the auxiliary breaker being opened. By disconnecting the snubber capacitor, an uncontrolled discharging of the capacitor through the disconnector and the main breaker, and the resulting non-zero current flowing through the disconnector during the breaking action, may be avoided. Further, a method of an HVDC hybrid circuit breaker is provided.

Abstract: Apparatuses and methods for protecting a circuit from an over-limit electrical condition are disclosed. One example apparatus includes a protection circuit coupled to a circuit to be protected. The circuit to be protected is coupled to a pad node. The protection circuit is configured to conduct current from the pad node to a reference voltage node to protect the circuit from an over-limit electrical condition. The protection circuit has a trigger circuit coupled to the pad node and configured to trigger a shunt circuit to conduct current from the pad node to the reference voltage node responsive to a voltage provided to the pad node having a voltage exceeding a trigger voltage. In some embodiments, the trigger circuit is matched to the circuit being protected.

Abstract: A three-phase AC power controller has three strands, each having an input and an output. Five pairs of valves are connected antiparallel for rotating field reversal. The first input is connected to the first output by way of a first pair, the second input is connected to the second output by way of a second pair and to the third output by way of a third pair, and the third input is connected to the second output by way of a fourth pair and to the third output by way of a fifth pair. An RC half-branch is connected as a snubber circuit to each input and to each output. These RC half-branches are each interconnected via a transverse connection.

Abstract: A matrix converter includes a plurality of semiconductor switch modules, and a plurality of snubber modules each having a plurality of capacitors and a plurality of diodes. Each of the snubber modules has a terminal group projecting outward, a first terminal, and a second terminal. The first and second terminals project from positions different from the terminal group, and are connected to an external circuit provided outside the matrix converter. Terminals of the terminal group are connected to terminals of a corresponding semiconductor switch module. The first terminals of the plurality of snubber modules are connected to one another via a first bus bar, and the second terminals are connected to one another via a second bus bar.

Abstract: A semiconductor device includes: a parallel connection structure 1 between a first node and a second node; a first snubber device and a second snubber device having a clamp level that is the same as or higher than the output voltage of a power source section. One terminal of the first snubber device is connected through the first node to one end of the parallel connection structure, the opposite terminal of the first snubber device is connected through a third node to one terminal of the second snubber device, and the opposite terminal of the second snubber device is connected through the second node to the opposite end of the parallel connection structure. Electric power is fed back to the power source section through the second and third nodes.

Abstract: A snubber circuit includes: a capacitor including a first terminal and a second terminal, where the first terminal of the capacitor is electrically connected to a first terminal of the snubber circuit; and a Bipolar Junction Transistor (BJT), where one of the emitter and the collector of the BJT is electrically connected to the second terminal of the capacitor, and the other one of the emitter and the collector of the BJT is electrically connected to a second terminal of the snubber circuit. The snubber circuit can be electrically connected in parallel to an active component or a load to protect the circuitry connected to the load, and more particularly to absorb spike or noise generated during high-frequency switching of the active component to recycle energy, in order to achieve the goal of reducing spike voltages and enhancing efficiency.

Abstract: An overvoltage protection method and circuit includes a positive supply input node, an output node, and a negative supply node. The overvoltage protection circuit further includes a first functional circuit configured to turn ON a MOSFET and maintain it in a low resistance state. A second functional circuit is configured to detect an overvoltage and control the gate of the MOSFET to regulate a voltage at the output node. A third functional circuit is configured to provide a startup wherein the overvoltage protection circuit is not damaged and/or to regulate an operating voltage such that an overvoltage does not appear on the overvoltage protection circuit. The external components include the MOSFET, which has a gate coupled to the output of the charge pump of the overvoltage protection circuit.

Abstract: A protection ability of a power supply control circuit is improved so as to protect an output transistor against a back electromotive voltage from a load, a dump surge voltage, and a positive spike surge voltage which has a smaller energy but is higher than the dump surge voltage. The power supply control circuit includes: an output MOS transistor (power semiconductor device) connected between a first power supply terminal and an output terminal; a load connected to the output terminal; a first dynamic clamping circuit for controlling a voltage difference between a first power supply line and the output terminal; and a first switch connected between the first dynamic clamping circuit and the output MOS transistor, in which a conductive state is determined according to a result of comparison between a reference voltage and a voltage at the output terminal.

Abstract: A matrix converter includes a plurality of semiconductor switch modules, and a plurality of snubber modules each having a plurality of capacitors and a plurality of diodes. Each of the snubber modules has a terminal group projecting outward, a first terminal, and a second terminal. The first and second terminals project from positions different from the terminal group, and are connected to an external circuit provided outside the matrix converter. Terminals of the terminal group are connected to terminals of a corresponding semiconductor switch module. The first terminals of the plurality of snubber modules are connected to one another via a first bus bar, and the second terminals are connected to one another via a second bus bar.

Abstract: Power at a selected frequency in the high frequency region of the spectrum is supplied by a power converter having a wide range of input voltages. The power converter uses a source oscillator and a NOR gate. The source oscillator generates a rectangular wave at the selected frequency and supplies that signal to one of the NOR gate inputs. The rectangular wave is differentiated and the differentiated signal is supplied to the second NOR input along with a feedback signal from an amplifier controlled by the NOR gate's output.

Abstract: A main transistor and a reverse current prevention transistor are provided in series between an input terminal and an output terminal. An input diode is provided between a connection point of the reverse current prevention transistor and the main transistor and a reference voltage terminal in such a direction that the anode becomes the reference voltage terminal side. A control unit controls the gate voltage of the main transistor according to a DC voltage. The reverse current prevention transistor is arranged in such a direction that the anode of its body diode becomes the input terminal side. The reverse current prevention transistor is biased to be turned on in a normal state that the input terminal becomes high potential and the reference voltage terminal becomes low potential.

Abstract: An overvoltage protection circuit includes an output transistor coupled between a power supply and an output terminal, the output terminal including a terminal for being coupled to a load and a dynamic clamping circuit and a clamp selection transistor coupled in series between the power supply terminal and a control terminal of the output transistor. The clamp selection transistor is coupled between the dynamic clamping circuit and a control terminal of the output transistor. In addition, the clamp selector transistor includes an N-channel type transistor, a control terminal of the N-channel type transistor being coupled to a ground potential.

Abstract: In one embodiment, a protection circuit includes a linear regulator remains enabled during a portion of a time while limiting an output voltage of the linear regulator to a first value.

Abstract: Integrated snubber device on a semiconductor basis for wiring an electric network for absorbing electric energy from an electric energy store, of an electric network, including at least two terminals for being connected to the electric network to be wired, an electric resistor structure, and a reactance structure, which are connected between the terminals.

Abstract: A circuit arrangement for limiting excessive voltages by a forward delay time of a first diode is described. The first diode is alternately switched in a non-conducting direction and a conducting direction by switching a circuit element. The first diode is series-connected to a first capacitor and a pre-charging circuit is provided for the first capacitor, the pre-charging circuit charging the first capacitor while the first diode is switched in the non-conducting direction. The pre-charging circuit charges the first capacitor more strongly than an excessive voltage of the first diode with regard to the amount.

Abstract: Over-voltage indicator and related circuit and method. The over-voltage indicator can work with an I/O circuit of a chip for detecting over-voltage in an I/O pad and providing an indication signal accordingly. When over-voltage does not happen, the over-voltage indicator continues to detect a signal level of the I/O pad and keeps the indication signal low. Once over-voltage is detected, the over-voltage indicator pauses detecting, asserts a high level in the indication signal, and periodically resumes detecting until end of over-voltage is detected. With informing provided by the indication signal, a core cell of the chip can perform proper operation to reduce potential damage caused by over-voltage.

Abstract: A circuit for protecting a DUT is disposed in parallel with a DUT which is supplied with current via wirings and switchable between conducting and non-conducting state. The circuit is switchable between conducting and non-conducing state and switched from non-conducting state to conducting state as the DUT is switched from conducting state to non-conducting state.

Abstract: An interface system may be used to connect an electrical device to an electrical bus. The interface system may include a first end and a second end in electrical communication with the first end. Where the interface system is used to connect an electrical device to an electrical bus, the first end may be connected to the electrical bus and the second end may be connected to the electrical device. The interface system may also include a reverse current blocking circuit configured to block current from flowing from the second end to the first end. Additionally, the interface system may include a discharge circuit electrically connected between the first end and the second end for discharging the blocked current.

Abstract: A powered device includes a voltage protection circuit, two outputs, a switch, and a snubber circuit. The two outputs of the integrated circuit may be coupled to an external transformer. The snubber circuit of the integrated circuit is responsive to the switch and is coupled with respect to the two outputs to direct energy from at least one of the two outputs to the voltage protection circuit.

Abstract: A protection ability of a power supply control circuit is improved so as to protect an output transistor against a back electromotive voltage from a load, a dump surge voltage, and a positive spike surge voltage which has a smaller energy but is higher than the dump surge voltage. The power supply control circuit includes: an output MOS transistor (power semiconductor device) connected between a first power supply terminal and an output terminal; a load connected to the output terminal; a first dynamic clamping circuit for controlling a voltage difference between a first power supply line and the output terminal; and a first switch connected between the first dynamic clamping circuit and the output MOS transistor, in which a conductive state is determined according to a result of comparison between a reference voltage and a voltage at the output terminal.

Abstract: A snubber circuit for use with an integrated power supply control circuit incorporating a transformer and a lateral power MOSFET on a single silicon chip. A capacitor is provided in circuit with the MOSFET and first resistor and diode are in series with each other and the capacitor. A second resistor and diode are also in series with each other and the capacitor. The diodes provide for first current flow in one and an opposite direction and the resistors provide first and second levels of resistance respectively for damping and turn on. In another embodiment, first and second resistors are provided in series with the capacitor, and a diode is connected across one of the resistors.

Abstract: Self-powered supplies are presented for powering a power converter switch driver with power obtained from an associated snubber circuit, in which a supply circuit and a snubber circuit are connected in a series path across the switch terminals with the supply circuit receiving electrical power from the snubber and providing power to the switch driver.

Abstract: A first bypass circuit has first and second nodes. The first load circuit is connected between the first node and a signal input terminal of the second drive circuit. The second load circuit has substantially the same impedance as the first load circuit, and is connected between the second node and the reference potential terminal of the second drive circuit. The first drive circuit has the same reference potential as the input buffer. The second bypass circuit passes a signal of a predetermined frequency or higher between a current path formed between the first load circuit and the signal input terminal of the second drive circuit and a current path formed between the second load circuit and the reference potential terminal of the second drive circuit. The first bypass circuit passes a signal of a predetermined frequency or higher between the first and second nodes.

Abstract: Over-voltage indicator and related circuit and method. The over-voltage indicator can work with an I/O circuit of a chip for detecting over-voltage in an I/O pad and providing an indication signal accordingly. When over-voltage does not happen, the over-voltage indicator continues to detect a signal level of the I/O pad and keeps the indication signal low. Once over-voltage is detected, the over-voltage indicator pauses detecting, asserts a high level in the indication signal, and periodically resumes detecting until end of over-voltage is detected. With informing provided by the indication signal, a core cell of the chip can perform proper operation to reduce potential damage caused by over-voltage.

Abstract: A method and an arrangement for controlling phase-specific thyristors of a half-controlled network bridge, the method comprising identifying a thyristor to be controlled on the basis of the magnitude of phase voltage, controlling the thyristor by switching on a voltage in its gate current circuit to achieve a gate current. The controlling of the thyristor comprises the steps of leading the gate current through an inductive component of the gate current circuit to the gate of the thyristor, determining the magnitude of the gate current, alternately switching off the voltage in the gate current circuit, when the gate current is higher than a preset limit, and switching on the voltage in the gate current circuit, when the gate current is lower than a preset limit.

Abstract: A snubber circuit and corresponding power converter topology for controlling the voltage across the resonant capacitor at turn on of a control switch so as to suppress a spike at the switch caused by the large current pulse and parasitic inductance of the power converter. The suppression of the spike reduces conduction losses and increases efficiency. According to one embodiment, the snubber circuit in a boost converter topology includes a second winding tapped from the main boost inductor and connected in series with a first diode and a second diode. A resonant capacitor and the second diode are connected in a series combination which is in parallel with the main boost diode. The second winding is connected in series with the first diode and the second diode between the output terminals of the converter. Alternatively, the snubber circuit is used in flyback, buck, and forward converter topologies.

Abstract: A surge protective circuit and a noise filter circuit are provided in a power-supplying line, the surge protective circuit is adapted for protecting a switching device from surge voltage generated during operation of an electric motor and the noise filter circuit is adapted for absorbing noise generated during operation of the switching device, each of the surge protective circuit and the noise filter circuit include a plurality of elements, wherein at least one of the plurality of the elements constructing the surge protective circuit is used as at least one of the plurality of the elements constructing the noise filter circuit in common with each other.

Abstract: Integrated snubber device on a semiconductor basis for wiring an electric network for absorbing electric energy from an electric energy store, of an electric network, including at least two terminals for being connected to the electric network to be wired, an electric resistor structure, and a reactance structure, which are connected between the terminals.

Abstract: The invention relates to an energy transfer circuit. The energy transfer circuit has a first electromagnetic induction device, electrically connected to a first power supply node; a first switch circuit for connecting the first electromagnetic induction device and a second power supply node according to a first control signal; a snubber electrically connected between the first electromagnetic induction device and the second power supply node; a second electromagnetic induction device, coupled to the first electromagnetic induction device and electrically connected to the snubber and the second power supply node; and a third electromagnetic induction device coupled to the first and second electromagnetic induction devices and electrically connected to an output port of the energy transfer circuit.

Abstract: A snubber circuit for use with an integrated power supply control circuit incorporating a transformer and a lateral power MOSFET on a single silicon chip. A capacitor is provided in circuit with the MOSFET and first resistor and diode are in series with each other and the capacitor. A second resistor and diode are also in series with each other and the capacitor. The diodes provide for first current flow in one and an opposite direction and the resistors provide first and second levels of resistance respectively for damping and turn on.

Abstract: It is an object of the invention to realize a snubber module which is small in size, and which can be easily handled, thereby miniaturizing a power conversion apparatus. In the invention, a snubber module (10) is configured so that twelve snubber diodes and a snubber capacitor which constitute a snubber circuit for suppressing a surge voltage are enclosed in a resin mold (101), and a P-side lead wire (103) and an N-side lead wire (104) which are two capacitor external terminals that are connected respectively to two terminals of the snubber capacitor, and six diode external terminals (102) which are connected respectively to connecting portions where respective two of the twelve snubber diodes are connected to each other are exposed from the resin mold (101).

Abstract: A field effect transistor (FET) is used as the protection circuit. The gate is grounded through an electrical element. The voltage source is connected to the drain of the FET. The load is connected to the source of the FET. At low input voltages, the FET conducts in body diode mode. At higher input voltages, the FET turns “on” and conducts more efficiently.