Abstract: There is provided a backlight unit driver capable of driving multi-channel lamps of a backlight unit, especially LED lamps, by supplying a driving power to the lamps using a single transformer and maintaining the current balance of the driving power supplied to each of the lamps.

Abstract: A power supply having a maximum power point tracking function that controls power switching so that a detected power value is within a reference range having a maximum power point in a predetermined current-voltage curve includes: a converter section switching input power and converting the switched input power into predetermined DC power; and a maximum power point tracking section detecting a power value determined according to a switching operation of the converter section among power values included in a predetermined power-voltage curve, and controlling the switching operation of the converter section so that the detected power value is located within a predetermined reference range having a maximum power value among the power values included in the power-voltage curve.

Abstract: Disclosed is a multi-output DC/DC converter controlling power-conversion switching in synchronization with a frequency of one output voltage among multiple output voltages in an LLC resonant DC/DC converter. The multi-output DC/DC converter includes a power conversion circuit performing alternate switching on an input DC voltage to output multiple DC voltages including a first DC voltage and a second DC voltage each having a preset voltage level, and a control circuit controlling the alternate switching of the power conversion circuit in synchronization with a preset resonant frequency.

Abstract: The present invention provides an LED driving circuit including: an inverter unit for switching an input power source; a plurality of transformers including a plurality of primary windings connected to the inverter unit and connected to each other in series and a plurality of secondary windings each of which is coupled with each of the primary windings; a plurality of rectification units each of which is connected to each of the secondary windings; and a plurality of LEDs each of which is connected to each of the rectification units.

Abstract: There is provided a backlight driving system for a liquid crystal display that can reduce size and weight of a product because a DC-DC converter is not used when commercial AC power is converted into lamp driving power. A backlight driving system for a liquid crystal display according to an aspect of the invention includes a power supply unit converting commercial alternating current (AC) power into direct current (DC) power having a voltage level set beforehand, an inverter unit converting the DC power from the power supply unit into AC power at a one-to-one conversion ratio set beforehand, a boosting unit boosting the AC power from the inverter unit into lamp lighting power set beforehand; and a lamp group receiving the lamp lighting power from the boosting unit to emit light.

Abstract: There is provided a variable switching frequency type power supply that can achieve high efficiency by fixing a switching duty cycle to 50% and varying switching frequency. A variable switching frequency type power supply according to an aspect of the invention may include: a switching unit switching input power; a transformation unit converting a voltage level of the power switched by the switching unit into a predetermined voltage level; a rectification unit rectifying the power converted by the transformation unit; and a control unit fixing a switching duty cycle of the switching unit to a predetermined switching duty cycle, and varying switching frequency of the switching unit according to a voltage level of output power.

Abstract: The present invention relates to power supplies, and more particularly, to a power supply having a maximum power point tracking function that can reduce manufacturing costs and circuit size by using a maximum power point tracking section with a simplified circuit in a solar photovoltaic power generator supplying power using sunlight instead of using a micro controller, the maximum power point tracking section that controls power switching according to a result of integration of a value obtained by dividing a power variation by a voltage variation to track a maximum power value.

Abstract: The present invention relates to power supplies, and more particularly, to a power supply having a maximum power point tracking function that controls power switching so that a detected power value is within a reference range having a maximum power point in a predetermined current-voltage curve. A power supply having a maximum power point tracking function according to an aspect of the invention includes: a converter section switching input power and converting the switched input power into predetermined DC power; and a maximum power point tracking section detecting a power value determined according to a switching operation of the converter section among power values included in a predetermined power-voltage curve, and controlling the switching operation of the converter section so that the detected power value is located within a predetermined reference range having a maximum power value among the power values included in the power-voltage curve.

Abstract: There is provided an integrated type transformer that reduces the volume by integrating a plurality of transformers transmitting power for driving a plurality of lamps in an inverter circuit for an LCD into one transformer structure. An integrated type transformer according to an aspect of the invention includes a bobbin unit including a bobbin body having a predetermined length and a through hole therein in a longitudinal direction of the bobbin unit, and a core unit including an inner core inserted into the through hole of the bobbin unit, and an outer core formed along one surface in the longitudinal direction among outer circumferential surfaces of the bobbin unit and electromagnetically coupled to the inner core to form one magnetic path.

Abstract: A plasma display device includes first to fourth transistors and a plurality of first electrodes. A first terminal of a first capacitor is connected to a power supply supplying a voltage. A second terminal of a second capacitor connected to a second terminal of the first capacitor is connected to a ground terminal. A first diode is connected to the first electrodes through a first inductor and a fifth transistor, which forms a voltage rising path. A second diode is connected to the first electrodes through a second inductor and a sixth transistor, which forms a voltage falling path. A third diode is connected to the third transistor and the second diode, which forms a voltage sustaining path during a voltage rising period. A fourth diode is connected to the second transistor and the first diode, which forms a voltage sustaining path of a voltage falling period.

Abstract: There is provided a high voltage power supply capable of reducing voltage stress of a voltage multiplying device. The high voltage power supply includes: a power converter switching on/off and converting an input direct current power into a direct current power having a preset voltage level; and a voltage multiplier including a first multiplying cell multiplying the voltage level of the direct current power from the power converter, wherein the first multiplying cell includes: first and second capacitors charging the direct current power from the power converter, respectively; a first diode providing a path for transferring the direct current power when the power converter is switched off; and a second diode providing a path for transferring the direct current power when the power converter is switched on.

Abstract: Disclosed is a multi-output DC/DC converter controlling power-conversion switching in synchronization with a frequency of one output voltage among multiple output voltages in an LLC resonant DC/DC converter. The multi-output DC/DC converter includes a power conversion circuit performing alternate switching on an input DC voltage to output multiple DC voltages including a first DC voltage and a second DC voltage each having a preset voltage level, and a control circuit controlling the alternate switching of the power conversion circuit in synchronization with a preset resonant frequency.

Abstract: Provided is a flyback DC/DC converter for a power supply. In the flyback DC/DC converter, a flyback driver unit provides a primary current. A transformer includes a plurality of secondary coils for inducing energy from the primary coil receiving the primary current. A rectifier unit includes a plurality of rectifier diodes for rectifying secondary currents of the corresponding secondary coils of the transformer. A plurality of clamp diodes are connected in series to the corresponding rectifier diodes of the rectifier unit in a forward direction to clamp ringing voltage across the corresponding rectifier diodes when the power switch is turned off. Accordingly, the voltage across the rectifier diode on the secondary side can be reduced such that it is lower than the output voltage. Also, it is possible to remove the ringing voltage of the rectifier diode and to enhance the efficiency of the flyback DC/DC converter.

Abstract: There is provided a backlight driving system for a liquid crystal display that can reduce size and weight of a product because a DC-DC converter is not used when commercial AC power is converted into lamp driving power. A backlight driving system for a liquid crystal display according to an aspect of the invention includes a power supply unit converting commercial alternating current (AC) power into direct current (DC) power having a voltage level set beforehand, an inverter unit converting the DC power from the power supply unit into AC power at a one-to-one conversion ratio set beforehand, a boosting unit boosting the AC power from the inverter unit into lamp lighting power set beforehand; and a lamp group receiving the lamp lighting power from the boosting unit to emit light.

Abstract: There is provided an integrated type transformer that reduces the volume by integrating a plurality of transformers transmitting power for driving a plurality of lamps in an inverter circuit for an LCD into one transformer structure. An integrated type transformer according to an aspect of the invention includes a bobbin unit including a bobbin body having a predetermined length and a through hole therein in a longitudinal direction of the bobbin unit, and a core unit including an inner core inserted into the through hole of the bobbin unit, and an outer core formed along one surface in the longitudinal direction among outer circumferential surfaces of the bobbin unit and electromagnetically coupled to the inner core to form one magnetic path.

Abstract: Provided is a backlight driving apparatus for a non-emissive display device which comprises an inverter (or lamp driver) (110) that converts a DC voltage to a preset voltage, a lamp (120) that emits light in response to the input of the converted voltage from the inverter (or lamp driver) (110), a detector (130) that detects electric current or brightness at the lamp, a controller (140) that controls the pulse width of a digital dimming signal in order to provide an adequate control of the electric current or brightness according to a lamp brightness command, a signal generator (150) that generates a signal with fixed frequency and fixed duty ratio for optimizing the operation of the inverter (or lamp driver) (110) and a digital dimmer (160) that generates an inverter driving signal from the logical intersection of the digital dimming signal generated by the controller (140) and the signal generated by the signal generator (150).

Abstract: A plasma display device includes first to fourth transistors and a plurality of first electrodes. A first terminal of a first capacitor is connected to a power supply supplying a voltage. A second terminal of a second capacitor connected to a second terminal of the first capacitor is connected to a ground terminal. A first diode is connected to the first electrodes through a first inductor and a fifth transistor, which forms a voltage rising path. A second diode is connected to the first electrodes through a second inductor and a sixth transistor, which forms a voltage falling path. A third diode is connected to the third transistor and the second diode, which forms a voltage sustaining path during a voltage rising period. A fourth diode is connected to the second transistor and the first diode, which forms a voltage sustaining path of a voltage falling period.

Abstract: Provided is a flyback DC/DC converter for a power supply. In the flyback DC/DC converter, a flyback driver unit provides a primary current. A transformer includes a plurality of secondary coils for inducing energy from the primary coil receiving the primary current. A rectifier unit includes a plurality of rectifier diodes for rectifying secondary currents of the corresponding secondary coils of the transformer. A plurality of clamp diodes are connected in series to the corresponding rectifier diodes of the rectifier unit in a forward direction to clamp ringing voltage across the corresponding rectifier diodes when the power switch is turned off. Accordingly, the voltage across the rectifier diode on the secondary side can be reduced such that it is lower than the output voltage. Also, it is possible to remove the ringing voltage of the rectifier diode and to enhance the efficiency of the flyback DC/DC converter.