Abstract: Disclosed are a switch driving device, in which individual zero voltage switching control of a first switch element and a second switch element forming a bidirectional switch is performed, and a switching power supply including a primary winding to which an alternating-current input voltage is applied, a secondary winding electromagnetically coupled to the primary winding, the bidirectional switch connected in series with the primary winding, a resonance capacitor connected in parallel with at least one of the bidirectional switch and the primary winding, a full-wave rectifier circuit that performs full-wave rectification of an induced voltage occurring in the secondary winding, a smoothing capacitor that smooths output of the full-wave rectifier circuit, and the switch driving device that drives the bidirectional switch.

Abstract: Disclosed are a switch driving device, in which individual zero voltage switching control of a first switch element and a second switch element forming a bidirectional switch is performed, and a switching power supply including a primary winding to which an alternating-current input voltage is applied, a secondary winding electromagnetically coupled to the primary winding, the bidirectional switch connected in series with the primary winding, a resonance capacitor connected in parallel with at least one of the bidirectional switch and the primary winding, a full-wave rectifier circuit that performs full-wave rectification of an induced voltage occurring in the secondary winding, a smoothing capacitor that smooths output of the full-wave rectifier circuit, and the switch driving device that drives the bidirectional switch.

Abstract: Disclosed are a switch driving device, in which individual zero voltage switching control of a first switch element and a second switch element forming a bidirectional switch is performed, and a switching power supply including a primary winding to which an alternating-current input voltage is applied, a secondary winding electromagnetically coupled to the primary winding, the bidirectional switch connected in series with the primary winding, a resonance capacitor connected in parallel with at least one of the bidirectional switch and the primary winding, a full-wave rectifier circuit that performs full-wave rectification of an induced voltage occurring in the secondary winding, a smoothing capacitor that smooths output of the full-wave rectifier circuit, and the switch driving device that drives the bidirectional switch.

Abstract: Disclosed are a rectifying circuit and a switched-mode power supply. The rectifying circuit includes a first rectifying section for rectifying a positive induced voltage generated across a secondary winding of a transformer, a second rectifying section for rectifying a negative induced voltage generated across the secondary winding, and an inductance section connected between the first rectifying section and the second rectifying section. The switched-mode power supply includes a transformer having a primary winding and a secondary winding, a drive circuit for switchingly driving the primary winding of the transformer, and the rectifying circuit connected to the secondary winding of the transformer.

Abstract: Disclosed are a switch driving device, in which individual zero voltage switching control of a first switch element and a second switch element forming a bidirectional switch is performed, and a switching power supply including a primary winding to which an alternating-current input voltage is applied, a secondary winding electromagnetically coupled to the primary winding, the bidirectional switch connected in series with the primary winding, a resonance capacitor connected in parallel with at least one of the bidirectional switch and the primary winding, a full-wave rectifier circuit that performs full-wave rectification of an induced voltage occurring in the secondary winding, a smoothing capacitor that smooths output of the full-wave rectifier circuit, and the switch driving device that drives the bidirectional switch.

Abstract: Disclosed are a rectifying circuit and a switched-mode power supply. The rectifying circuit includes a first rectifying section for rectifying a positive induced voltage generated across a secondary winding of a transformer, a second rectifying section for rectifying a negative induced voltage generated across the secondary winding, and an inductance section connected between the first rectifying section and the second rectifying section. The switched-mode power supply includes a transformer having a primary winding and a secondary winding, a drive circuit for switchingly driving the primary winding of the transformer, and the rectifying circuit connected to the secondary winding of the transformer.

Abstract: A power supply device has a switch and a coil connected in series with alternating-current input power. A first rectifier connected across the coil performs boost rectification, and a voltage across an output smoothing capacitor is charged to obtain output power.

Abstract: A power supply device has a switch and a coil connected in series with alternating-current input power. A first rectifier connected across the coil performs boost rectification, and a voltage across an output smoothing capacitor is charged to obtain output power.

Abstract: A drive circuit includes a control circuit configured to output a polarity signal for controlling ON/OFF of a driving switch, a pulse transformer, electrically connected to the control circuit, configured to transmit the polarity signal, and a discharge circuit, electrically connected to the pulse transformer and a gate terminal of the driving switch, configured to discharge an electric charge accumulated in the gate terminal based on the polarity signal. When the polarity signal having a first polarity is applied to the gate terminal through the pulse transformer, the driving switch is switched to and maintained in an ON state by accumulating the electric charge in the gate terminal. When the polarity signal having a second polarity different from the first polarity is applied to the discharge circuit through the pulse transformer, the driving switch is switched to an OFF state by discharging the electric charge by the discharge circuit.

Abstract: A drive circuit includes a control circuit configured to output a polarity signal for controlling ON/OFF of a driving switch, a pulse transformer, electrically connected to the control circuit, configured to transmit the polarity signal, and a discharge circuit, electrically connected to the pulse transformer and a gate terminal of the driving switch, configured to discharge an electric charge accumulated in the gate terminal based on the polarity signal. When the polarity signal having a first polarity is applied to the gate terminal through the pulse transformer, the driving switch is switched to and maintained in an ON state by accumulating the electric charge in the gate terminal. When the polarity signal having a second polarity different from the first polarity is applied to the discharge circuit through the pulse transformer, the driving switch is switched to an OFF state by discharging the electric charge by the discharge circuit.

Abstract: An open magnetic circuit coil (6) is arranged on a line connecting a battery (1) to a charger (CH1). Furthermore, a resistor (2) is connected in series with a large-capacitance electrolytic capacitor (7) for smoothing a charger output which is connected to the output of the charger (CH1). This can suppress an abrupt change in current flowing in the connection line between the battery (1) and the charger (CH1) in connection between plugs (3a, 3b).

Abstract: Provided is a switching power supply apparatus capable of suppressing heat generation from a power supply to improve the efficiency of conversion during a power supply operation and accurately detecting only a current flowing through a load to achieve more stabile control. Since a first closed loop made up of a fourth diode (27d), a third inductor (25c) and a fourth electronic switch (24d) and a second closed loop made up of a second diode (27b), a first inductor (25a) and a second electronic switch (24b) do not include a fourth inductor (25d) and a second inductor (25b) through which an AC output current supplied to a load (28) flows, an unnecessary current does not flow through the first or second closed loop.

Abstract: A plurality of power supply circuits Z1? are provided according to a load capacity. The power supply circuits Z1? have sides connected in parallel on the side of a direct current input Vi and have sides connected in series on the sides of alternating current outputs Ao. A rectifying circuit DC1 is connected via a resonance circuit Z2 across a combined output of the serially connected sides of the power supply circuits Z1? on the sides of the alternating current outputs Ao. Switching frequencies are simultaneously controlled by a single control signal outputted from a control circuit S1 based on a direct current output voltage detected from the rectifying circuit DC1 through a detection resistor R5.

Abstract: An object of the present invention is to provide a switching power supply which can stably determine whether an overcurrent occurs or not on the secondary side. A sample voltage corresponding to a load current value detected by detection resistors R7 and R8 is compared with a reference voltage by an input-side transistor Q4 and an output-side transistor Q3 which compose a first current mirror circuit 14, so that it is possible to determine whether an overcurrent occurs or not. Moreover, a current passing through the output circuit of the transistor Q3 is temperature-compensated by a second current mirror circuit 17 made up of transistors Q6 and Q5.

Abstract: An open magnetic circuit coil (6) is arranged on a line connecting a battery (1) to a charger (CH1). Furthermore, a resistor (2) is connected in series with a large-capacitance electrolytic capacitor (7) for smoothing a charger output which is connected to the output of the charger (CH1). This can suppress an abrupt change in current flowing in the connection line between the battery (1) and the charger (CH1) in connection between plugs (3a, 3b).

Abstract: Provided is a switching power supply apparatus capable of suppressing heat generation from a power supply to improve the efficiency of conversion during a power supply operation and accurately detecting only a current flowing through a load to achieve more stabile control. Since a first closed loop made up of a fourth diode (27d), a third inductor (25c) and a fourth electronic switch (24d) and a second closed loop made up of a second diode (27b), a first inductor (25a) and a second electronic switch (24b) do not include a fourth inductor (25d) and a second inductor (25b) through which an AC output current supplied to a load (28) flows, an unnecessary current does not flow through the first or second closed loop.

Abstract: A plurality of power supply circuits Z1? are provided according to a load capacity. The power supply circuits Z1? have sides connected in parallel on the side of a direct current input Vi and have sides connected in series on the sides of alternating current outputs Ao. A rectifying circuit DC1 is connected via a resonance circuit Z2 across a combined output of the serially connected sides of the power supply circuits Z1? on the sides of the alternating current outputs Ao. Switching frequencies are simultaneously controlled by a single control signal outputted from a control circuit S1 based on a direct current output voltage detected from the rectifying circuit DC1 through a detection resistor R5.

Abstract: An object of the present invention is to provide a switching power supply which can stably determine whether an overcurrent occurs or not on the secondary side. A sample voltage corresponding to a load current value detected by detection resistors R7 and R8 is compared with a reference voltage by an input-side transistor Q4 and an output-side transistor Q3 which compose a first current mirror circuit 14, so that it is possible to determine whether an overcurrent occurs or not. Moreover, a current passing through the output circuit of the transistor Q3 is temperature-compensated by a second current mirror circuit 17 made up of transistors Q6 and Q5.

Abstract: A cold-cathode tube lighting device uniformly lights multiple cold-cathode tubes using a common power source, and the cold-cathode tube lighting device is effectively downsized by using ballast capacitors. A substrate is divided into blocks as many as the cold-cathode tubes. Each of the blocks includes two conductor layers each including two foils. A first foil of a first conductor layer is connected to a common low-impedance power supply. Between the two conductor layers, first ballast capacitors are formed in areas where the first foils are overlapped, second ballast capacitors are formed in areas where the first and second foils are overlapped, and the third ballast capacitors are formed in areas where the second foils are overlapped. Second foils are connected to first electrodes of the cold-cathode tubes.

Abstract: For the purpose of providing a resonant switching power supply device having a wide output voltage variable range by changing its switching frequency, the resonance circuit thereof comprises a switching transformer, a first resonance section connected in series with the switching transformer, and a second resonance section connected in parallel with the switching transformer, wherein the resonance frequency characteristic in the case that the DC load current is large is formed using the series-connected devices of the first resonance section, and the resonance frequency characteristic in the case that the DC load current is small is formed using the first resonance section, the second resonance capacitor of the second resonance section and the switching transformer.