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7323829 Minimizing bond wire power losses in integrated circuit full bridge CCFL drivers  
A technique is described that reduces parasitic losses in circuits used to drive current through a load. An example of a system according to the technique includes four switches in series with five...
7323824 Methods and apparatus for operating very high pressure short arc discharge lamps  
Methods and apparatus are provided for operating very high pressure short arc mercury discharge lamps primarily used for projection applications. The method includes controlling an alternating lamp...
7323828 LED current bias control using a step down regulator  
A step down switching regulator circuit that is particularly well-suited to drive high power LEDs includes a crossover conduction mode (XCM) control circuit that maintains operation at the...
7323825 Ballast integrated circuit (IC)  
A ballast integrated circuit (IC) for driving a first switching element and a second switching element includes: a variable gain amplifier (VGA) connected to a first input terminal connected to a...
7321205 Method and a controller to control power supply to a CCFL  
A CCFL (cold-cathode fluorescent lamp) driving system for digitally driving at least one CCFL, according to embodiments of the present invention, generally includes a transformer, a sense circuit...
7321206 LED driving apparatus  
An apparatus for driving an LED is provided. The driving apparatus may have an LED unit including at least one LED, and a current controlling unit for controlling the magnitude of current flowing...
7321199 Display apparatus and control method thereof  
A display apparatus and method in which a current ripple is decreased to improve characteristics of a display apparatus are provided. A display apparatus comprises a light source, a plurality of...
7321201 Basic halogen convertor IC  
A driving circuit for providing a control signal to a power semiconductor device for providing power to a filament lamp, said driving circuit comprising an oscillator for generating said control...
7321202 System and method for reducing flicker of compact gas discharge lamps at low lamp light output level  
A lamp lighting system allows dimming of a compact gas discharge lamp to a low light output level without perceptible flicker. When the system receives a request to dim the lamp to the low level,...
7319297 Balanced current lamp module and multi-lamp circuit  
A balanced current lamp module driven by a power source includes a first balanced current unit, a second balanced current unit and a balanced transformer. The first balanced current unit includes a...
7319298 Digitally controlled luminaire system  
The present invention provides a luminaire system capable of generating light of a desired chromaticity and luminous flux output during continuous operation with varying ambient operating...
7317286 Power supply apparatus for discharge lamp and control method for the same  
An apparatus supplies power to at least one discharge lamp. The apparatus includes a buck converter for regulating power supplied to at least one discharge lamp having a switching element driven by...
7317287 Circuit for an LED array  
A circuit arrangement for an LED array having two or more parallel-connected LED chains (LK 1 , LK 2 , LK 3 ), in each of which at least one LED ( 2 ) is arranged and, when there are two or more...
7315134 Power supply for a high voltage device  
Control of an output pulse width by a PWM control circuit is stopped and the initial pulse string having a fixed pulse width is outputted in order to obtain a power supply voltage rise within a...
7315130 Switching control for inverter startup and shutdown  
An electronic ballast circuit for a lamp is described, wherein the ballast comprises a power factor correction circuit coupled to an inverter circuit. The inverter circuit is further coupled to a...
7315138 Cold cathode fluorescent discharge lamp apparatus and operating method for same  
A discharge lamp operating device includes a voltage application unit that applies to a discharge lamp an alternating-current (AC) voltage for operation of the discharge lamp, and a frequency...
7312583 Apparatus and method for driving a lamp unit, and liquid crystal display device using the same  
An apparatus for driving a lamp comprising at least one lamp, an inverter to supply an alternating current signal, a transformer to boost the signal from the inverter and to supply the boosted...
7312584 Plasma-generation power-supply device  
A plasma-generation power-supply device includes a transformer connected to an alternating-current power-supply, a rectifier connected to the transformer, an inverter connected to the rectifier, a...
7312588 Ballast with frequency-diagnostic lamp fault protection circuit  
A ballast ( 20 ) for powering one or more gas discharge lamps ( 70,72,74,76 ) comprises an inverter ( 200 ) and a lamp fault protection circuit ( 400 ). Inverter ( 200 ) has an operating frequency...
7312586 Ballast power supply  
A high frequency ballast power supply for a high intensity discharge lamp includes a variable frequency voltage generating circuit for producing a regulated cyclical voltage. After ignition of the...
7309963 Smoothing circuit for improving EMC  
The present invention relates to an electronic ballast for discharge lamps, for example low-pressure discharge lamps, having a converter having a switching element and a two-part lamp inductor...
7307385 Boost controller capable of step-up ratio control  
A charge pump circuit boosts a voltage of a battery so as to generate a drive voltage for an LED. A constant current circuit generates a constant current to feed through the LED. A monitoring...
7307387 Switchable voltage converter  
A voltage converter, whose topology can be switched over between a boost converter and a SEPIC. The boost converter has ripple current compensation. As a result, the inductors used can be utilized...
7304438 Method and apparatus for preventing instabilities in radio-frequency plasma processing  
A method and apparatus for controlling a power supply to prevent instabilities due to dynamic loads in RF plasma processing systems, operating at frequencies of from 1 MHz and up, uses a...
7301288 LED buck regulator control IC  
A high speed buck control IC for constant LED current regulation. A continuous mode hysteretically controlled buck regulator monitors the load current using an accurate on-chip band-gap voltage...
7301289 Discharge lamp lighting control device  
The present discharge lamp lighting device is capable of rapidly breaking or restoring a lamp current or of rapidly reducing or restoring the lamp current. A discharge lamp lighting device,...
7294972 Feedback circuit for push-pull inverters  
A feedback circuit for push-pull inverters aims to improve the existing push-pull inverters that provide input electricity to a discharge lamp at a phase difference of 180 degrees without feedback...
7294974 Fixed operating frequency inverter for cold cathode fluorescent lamp having strike frequency adjusted by voltage to current phase relationship  
A method of driving a lamp that uses a DC to AC inverter that is connected to a primary winding of a transformer is disclosed. The inverter frequency is variable, and in one embodiment, may be...
7294973 Discharge tube lighting apparatus, light source apparatus, and display apparatus  
A discharge tube lighting apparatus is used to drive a plurality of discharge tubes. The apparatus includes a balance coil having a winding input end and a plurality of winding output ends to which...
7291989 Lighting control circuit for vehicle lighting equipment  
This disclosure relates to protecting a switching regulator by sensing immediately a change in an input voltage when the input voltage of the switching regulator is changed suddenly. When an input...
7291993 Method for driving a fluorescent lamp and an inverter circuit for performing such a method  
A method for driving a fluorescent lamp and an inverter circuit for performing the same are used to reduce an amount of electromagnetic interference (EMI) generated by a transformer and an...
7291992 Load failure protection circuit and discharge lamp driving apparatus  
The present invention provides a load failure protection circuit and a discharge lamp driving apparatus, which can exactly detect a failure even if the failure arises in any of a plurality of...
7288902 Color variations in a dimmable lighting device with stable color temperature light sources  
A method and system allow a lighting device having light sources with multiple color temperatures to vary a color temperature of the lighting device in response to changing dimming levels. The...
7288899 Light source, projector, and method of driving arc tube  
Aspects of the invention can relate to a light source that includes a light source lamp and an arc-tube drive unit. The light source lamp can include an arc tube that emits light between a pair of...
7288897 Circuit arrangement for operating at least one high pressure discharge lamp  
A circuit arrangement for operating at least one high-pressure discharge lamp having four switches in a full bridge arrangement, a first and a second switch forming the first half-bridge arm, and a...
7285919 Electronic ballast having improved power factor and total harmonic distortion  
An electronic ballast for driving a gas discharge lamp includes a rectifier, a valley-fill circuit, an inverter having first and second series-connected controllably conductive switches having...
7285923 Display apparatus and driving pulse control method thereof  
An apparatus and method is disclosed for controlling a display driving pulse to drive an LED display. In one embodiment, an RGB signal is received and a period during which all the LEDs are...
7285924 Driving circuit for LCD backlight lamps  
An LCD backlight driving circuit is provided for providing protection to LCD backlight lamps. In a preferred embodiment, the driving circuit for LCD backlight lamps comprises: a PWM controller...
7282867 Lighting device for discharge lamp  
An inductor for performing a chopper operation by turning on or off a first switching element MOSFET Q 1 and obtaining an increased voltage is arranged on the secondary side of a transformer 112 ...
7282870 Driving apparatus for CCFL  
The invention relates to a driving apparatus for a CCFL capable of easily providing a high output required to start the lamp. In the apparatus, an oscillator provides a reference signal in...
7282871 Backlight inverter for inductively detecting current  
A backlight inverter using electromagnetic induction and full-wave rectification at a second side of a main transformer includes a drive unit for generating a first voltage and a main transformer...
7279851 Systems and methods for fault protection in a balancing transformer  
An apparatus and methods for balancing current in multiple negative impedance gas discharge lamp loads. Embodiments advantageously include balancing transformer configurations that are relatively...
7279847 Pulse starting circuit  
A lamp ballast starting circuit and method for a gas discharge lamp is disclosed. The ballast starting circuit includes the inputs of the starting circuit connected to an inverter circuit, the...
7279958 Synthesized resonation for an EL driver circuit  
A driver circuit for an electroluminescent (EL) lamp that consumes less power and reduces electromagnetic interference (EMI). Electrical charge is stored during a discharge cycle of an AC signal...
7279844 Electronic ballast  
The invention relates to a ballast for low-pressure discharge lamps, comprising a controllable inverter circuit for the generation of a high-frequency supply voltage for a discharge lamp ( 1 ), a...
7277106 Scanning apparatus having a fluorescent lamp and control method thereof  
A scanning apparatus having a cold cathode fluorescent lamp includes a central processing unit (CPU) controlling a scan unit to be in one of the stand-by mode, a scan mode and a sleep mode and...
7276862 Stabilizer circuit for high-voltage discharge lamp  
A stabilizer circuit for a high-voltage discharge lamp is provided. The stabilizer comprises an electromagnetic interference (EMI) filter; a rectifying unit; a power factor correction (PFC)...
7276864 Discharge lamp lighting device and projection type image display apparatus having the same  
A computing circuit computes a target value of a current to be supplied to a discharge lamp and generates a pulse control signal for superpose a pulse current. Furthermore, the computing circuit...
7276861 System and method for driving LED  
A system drives one or plurality of LEDs regulating their brightness by controlling LEDs average current or voltage. The system includes a switching power converter and an integrated digital...
7275835 Projector for changing driving frequency for driving light source lamp within allowable frequency range  
A projector according to the present invention comprises a lamp driving control circuit for driving an ultra-high pressure mercury lamp at a driving frequency which is changed within an allowable...