Abstract: A reactor includes a toroidal coil including a winding wound to have an annular outer shape, a bus bar electrically connected to one end of the winding, and a current sensor that measures electric current flowing through the bus bar. The bus bar includes a crossing passing through a central area including an area inside an internal surface of the annular outer shape and an area in which the area extends along a central axis of the annular outer shape, and the current sensor measures electric current flowing through the crossing.

Abstract: This composite semiconductor device has a normally-on first field effect transistor and a normally-off second field effect transistor connected in series between first and second terminals, gates of the first and second field effect transistors being connected to second and third terminals, respectively, and N diodes being connected in series in a forward direction between a drain and a source of the second field effect transistor. Therefore, a drain-source voltage (Vds) of the second field effect transistor can be restricted to a voltage not higher than a withstand voltage of the second field effect transistor.

Abstract: A semiconductor device includes a lead frame 1 having a first lead 6, a second lead 7 and a third lead 8. A power transistor 2 is placed on the first lead 6, and the power transistor 2 is connected to the first lead 6. The power transistor 2 has a drain electrode on one side opposite to a first lead 6 side, and this drain electrode is connected to a Cu chip 3 on the power transistor 2. The Cu chip 3 is connected to the second lead 7 via Al wires 4. As a result, during wire bonding of the Al wires 4, it becomes possible to absorb shocks due to wire bonding by the Cu chip 3, or disperse pressure due to wire bonding by the Cu chip 3, or diffuse heat due to wire bonding by the Cu chip 3.

Abstract: This composite semiconductor device has a normally-on first field effect transistor and a normally-off second field effect transistor connected in series between first and second terminals, gates of the first and second field effect transistors being connected to second and third terminals, respectively, and N diodes being connected in series in a forward direction between a drain and a source of the second field effect transistor. Therefore, a drain-source voltage (Vds) of the second field effect transistor can be restricted to a voltage not higher than a withstand voltage of the second field effect transistor.

Abstract: A semiconductor device includes a photodiode formed using a silicon substrate, a wide-bandgap semiconductor layer formed on the silicon substrate and having a bandgap larger than that of silicon, and a switching element formed using the wide-bandgap semiconductor layer. The switching element is electrically connected to the photodiode so as to be on/off-controlled by a control signal from the photodiode.

Abstract: A semiconductor device includes a lead frame 1 having a first lead 6, a second lead 7 and a third lead 8. A power transistor 2 is placed on the first lead 6, and the power transistor 2 is connected to the first lead 6. The power transistor 2 has a drain electrode on one side opposite to a first lead 6 side, and this drain electrode is connected to a Cu chip 3 on the power transistor 2. The Cu chip 3 is connected to the second lead 7 via Al wires 4. As a result, during wire bonding of the Al wires 4, it becomes possible to absorb shocks due to wire bonding by the Cu chip 3, or disperse pressure due to wire bonding by the Cu chip 3, or diffuse heat due to wire bonding by the Cu chip 3.

Abstract: In a voltage clamp circuit, a normally-on type field-effect transistor having a negative threshold voltage has a drain connected to an input node, a source connected to an output node and grounded via a resistance element, and a gate supplied with an output voltage of a variable direct-current power supply. When a voltage at the output node becomes higher than a clamping voltage because of voltage drop of the resistance element, the field-effect transistor is tuned off. Accordingly, the output voltage is limited to be at most the clamping voltage. Thus, a response speed is higher than those of conventional voltage clamp circuits using diodes or the like.

Abstract: In a voltage clamp circuit, a normally-on type field-effect transistor having a negative threshold voltage has a drain connected to an input node, a source connected to an output node and grounded via a resistance element, and a gate supplied with an output voltage of a variable direct-current power supply. When a voltage at the output node becomes higher than a clamping voltage because of voltage drop of the resistance element, the field-effect transistor is tuned off. Accordingly, the output voltage is limited to be at most the clamping voltage. Thus, a response speed is higher than those of conventional voltage clamp circuits using diodes or the like.

Abstract: A semiconductor device includes a photodiode formed using a silicon substrate, a wide-bandgap semiconductor layer formed on the silicon substrate and having a bandgap larger than that of silicon, and a switching element formed using the wide-bandgap semiconductor layer. The switching element is electrically connected to the photodiode so as to be on/off-controlled by a control signal from the photodiode.

Abstract: A light is emitted from a light emitting element toward the other surface in a thickness direction of a scanning mirror which can be angularly displaced about an axial line. At least either one of a first light receiving portion and a second light receiving portion receives a light which is emitted from the light emitting element and reflected by a reflecting mirror. The first light receiving portion, the second light receiving portion, and the signal output section produce an electronic signal containing position information which indicates a position which is irradiated with the above-mentioned light. This position information indicates an amount of angular displacement of the scanning mirror. On the basis of this position information, a driving section scans the scanning mirror so that the predetermined irradiation position can be irradiated with a light emitted from a first light source.

Abstract: A light is emitted from a light emitting element toward the other surface in a thickness direction of a scanning mirror which can be angularly displaced about an axial line. At least either one of a first light receiving portion and a second light receiving portion receives a light which is emitted from the light emitting element and reflected by a reflecting mirror. The first light receiving portion, the second light receiving portion, and the signal output section produce an electronic signal containing position information which indicates a position which is irradiated with the above-mentioned light. This position information indicates an amount of angular displacement of the scanning mirror. On the basis of this position information, a driving section scans the scanning mirror so that the predetermined irradiation position can be irradiated with a light emitted from a first light source.