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Match Document Document Title
7436131 Thermal protection for lamp ballasts  
The output current of a ballast is dynamically limited when an over-temperature condition is detected in the ballast according to one of (i) a step function or (ii) a combination of step and...
7436129 Triple-loop fluorescent lamp driver  
A driver circuit provides electrical energy from a power source to a fluorescent lamp such as that used in a flat-panel or other liquid crystal display (LCD). The circuit includes a transformer...
7436128 Driving circuit for hot cathode fluorescent lamps  
A driving circuit for hot cathode fluorescent lamps aims to filter out signals with a voltage value lower than a duty voltage value of a switch unit through a commutation unit and a valley filled...
7436127 Ballast control circuit  
A ballast control circuit having a bridge driver for driving a transistor bridge of a ballast circuit coupled to a resonant ballast output stage including a lamp, the ballast control circuit...
7434941 System and method for arc lamp power control  
An arc lamp system includes an arc lamp, having a life span, a power supply, and a power control servo. The power supply is electrically coupled to the arc lamp and configured to provide power...
7432670 Device for turning on high-pressure discharge lamp and lighting apparatus equipped with the device  
Even if a DC output voltage of a step-down chopper circuit ( 3 ) is lowered from a value in a non-lighted state or a no-load state due to a discharge occurring between conductors ( 105 a ) in a...
7432668 Sensing light emitted from multiple light sources  
An apparatus is directed to controlling a light source. The apparatus provides at least one light source that emits a light signal at a discrete frequency and a reference signal at the discrete...
7432666 Cold cathode fluorescent lamp driving system  
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...
7432665 Method and device for driving a metal halide lamp  
A method for driving a lamp is described includes generating a light controlling DC electric field E with a desired direction and a desired strength inside the lamp such as to obtain a desirable...
7432664 Circuit for powering a high intensity discharge lamp  
A circuit ( 200 ) for powering a high intensity discharge lamp ( 10 ) comprises first and second input terminals ( 202,204 ), first and second output terminal ( 206,208 ), first and second inverter...
7432661 Electronic ballast having a flyback cat-ear power supply  
An electronic ballast for driving a gas discharge lamp includes a rectifier to convert an AC mains input voltage to a rectified voltage, a valley-fill circuit for producing a DC bus voltage, an...
7432660 IC-based low cost reliable electronic ballast with multiple striking attempts and end of lamp life protection  
The present invention relates generally to a simple, low cost ballast for fluorescent lamps that incorporates an integrated circuit and a number of ballast protection functions to cost effectively...
7429834 Multi-lamp driver with active current regulator  
An active current regulator circuit. In one embodiment, the active current regulator circuit includes a first input node for receiving a first reference electrical signal, a second input node for...
7429832 Light control fluorescent lamp and circuit thereof  
A light control circuit for use in light control fluorescent lamps comprises a filter and rectifier circuit ( 1 ), a frequency control and resonant circuit ( 2 ) and an ambient brightness signal...
7429830 Power control of a fluorescent lamp  
A fluorescent lamp ( 2 ), in particular a backlight lamp of a display device, is supplied with an alternating voltage, a frequency and an amplitude of which being greater during ignition than...
7429829 Discharge lamp lighting circuit with an open protection circuit  
A discharge lamp lighting circuit includes a plurality of discharge lamps, a driving circuit, a control circuit, an open protection circuit, which are connected in series. The open protection...
7425803 Method and circuit for driving a low voltage light emitting diode  
In a method for producing a control signal for regulating a drive current for driving an LED, a current through the LED is sensed, wherein the LED is driven by a power converter output, and wherein...
7425802 Discharge lamp lighting apparatus, luminaire and illumination system  
There is provided a high-intensity discharge lamp lighting apparatus to be loaded with a plurality of types of high-intensity discharge lamps and connected with any one of the lamps to be lighted,...
7425801 LED driving device for multiple color LED displays  
Driving voltages of an LED of each color are stored in applied voltage storage register 11, 12 or 13 , and the LED of each color is driven with independent driving voltage, whereby current...
7425800 Device for driving a light source module  
A driving device for driving a light source module ( 32 ) includes a switch circuit ( 30 ), a transformer circuit ( 31 ), a voltage sensing circuit ( 34 ), a current sensing circuit ( 35 ), and a...
7425777 Lighting circuit  
A lighting circuit includes a DC/DC converting circuit for boosting an input DC voltage so as to produce boosted DC power, a detecting circuit for producing a detection signal in response to the...
7423387 Apparatus and method for controlling colour and colour temperature of light generated by a digitally controlled luminaire  
The present invention provides a method and apparatus for controlling the correlated colour temperature (CCT) or colour of light produced by an array of light-emitting elements by providing...
7420829 Hybrid control for discharge lamps  
Control methods and apparatus are disclosed for operating an inverter at resonant mode, where the inverter adapts its frequency to the resonant tank characteristics before a lamp is struck, and...
7420336 Method of controlling cathode voltage with low lamp's arc current  
The embodiment disclosed herein relates to systems and methods to provide improvements to power delivery systems employed with lamps in general and fluorescent lamps in particular. In accordance...
7417616 Inverter for liquid crystal display  
An inverter for a display includes; an inverter controller generating a carrier signal for pulse width modulation and a lamp driving signal having on-time and off-time by pulse width modulating a...
7417384 Load control system and method  
A load control systems and methods. One embodiment of a load control system comprises at least two triac devices connected in parallel to a load, the at least two triac devices operable to deliver...
7417383 Apparatus and method of driving lamp of liquid crystal display device  
A method of driving a lamp of a liquid crystal display device includes generating a control signal; generating a first drive signal using the control signal; generating a second drive signal by...
7414373 Discharge lamp driving circuit and method of driving a discharge lamp  
A discharge lamp driving circuit includes an inverter, a ballast capacitor, a discharge lamp, and a lamp current detecting circuit. The inverter converts a DC voltage into an AC voltage with high...
7414372 Dimming ballast control circuit  
A dimming ballast control circuit for driving a ballast power switching circuit powering a gas discharge lamp. The circuit includes a driver circuit for driving high and low side switches of the...
7414371 Voltage regulation loop with variable gain control for inverter circuit  
A controller for an inverter provides variable gain control in a voltage regulation loop to prevent overshoot in an output voltage of the inverter. A feedback circuit senses the output voltage and...
7414369 Control system for fluorescent light fixture  
A control system comprises a switch and a control module that communicates with the switch and that samples a filament resistance of a fluorescent light when the switch is off and that selectively...
7411360 Apparatus and method for striking a fluorescent lamp  
A lamp inverter with continuous strike voltage facilitates faster striking of a fluorescent lamp, especially at cold temperatures. A frequency sweep generator sweeps the frequency of the lamp...
7411359 Apparatus and method for providing dimming control of lamps and electrical lighting systems  
Dimming of an electrical lamp of the type driven by a ballast is provided by a reactive power device in series between the AC supply and the ballast. The reactive power device provides a variable...
7411357 Liquid crystal and device of driving light source therefor  
A device of driving a plurality of lamps is provided, which includes: a transforming unit supplying driving voltages having inverted phases to adjacent lamps; and an inverter controlling the...
7408308 LED drive circuit, LED lighting device, and backlight  
To realize an LED drive circuit capable of feeding equal currents to parallel-connected LED circuits with a simple arrangement, there are provided a current source generating a temporally altering...
7408307 Ballast dimming control IC  
An electronic ballast provides dimming control, fault detection and safety features for overcurrent protection and hard switching at a half bridge. A voltage controlled oscillator supplies a...
7405523 Remote control of lighting  
An electronic ballast system controls one or more ballasts of HID or fluorescent lamps, which are controlled in an “on/off” manner by a ultra low power controller that is isolated for a primary...
7405522 Multiple failure detection shutdown protection circuit for an electronic ballast  
A shut-down circuit configured for use with an electronic ballast coupled to a lamp in a control path includes a device for sensing the electrical energy associated with the control path, and a...
7402960 LED-based lamp apparatus  
A LED-based lamp apparatus includes a LED unit having multiple LEDs connected in series, a step-up circuit for stepping up a power supply voltage by a switching action of a switching element to...
7402959 Phase sampling protection device  
A phase sampling protection device substantially includes a phase sampling circuit coupled between a tube circuit and a protection circuit. The phase sampling circuit captures a voltage signal and...
7402958 Display power partitioning  
According to one embodiment of the present invention, a voltage regulator is disclosed. The voltage regulator includes a step-down portion to step down an input voltage to a desired voltage when...
7402956 Ballast with zero voltage switching converter  
A ballast ( 10 ) for powering at least one gas discharge lamp ( 20 ) comprises a switching converter ( 100 ) and an inverter ( 900 ). Switching converter ( 100 ) includes a transistor ( 130 ) and a...
7400310 Pulse signal drive circuit  
A pulse signal drive circuit includes an energy storage device. A source of energy supplies a substantially constant flow of energy to the energy storage device. A switch circuit draws repetitive...
7400100 Discharge-lamp lighting apparatus and projector  
A discharge-lamp lighting apparatus includes a control circuit that determines electric power supplied to a high-pressure discharge lamp after the high-pressure discharge lamp is started by an...
7400095 Portable electric lighting fixture  
A portable electrical luminaire ( 1 ) having a supporting body ( 2 ) having an upper support end ( 2 a ) and having a lower support end ( 2 b ), having a lamp base ( 3 ) arranged on the upper...
7397203 Fluorescent ballast with unique dimming control  
A ballast includes circuitry to allow the level of the lighting to be adjusted as well as circuitry that interfaces the ballast to a control system via the power line. The ballast is provided for...
7397202 Brightness control circuit and backlight control module  
A brightness control circuit is used to control brightness of a light emitting module. A light sensor module generates a first current through itself according to a light intensity. A charging...
7397201 DC digital starting device  
A DC digital starting device includes a voltage-increasing circuit, a first feedback control circuit, a frequency-varying circuit, and a second feedback control circuit. The voltage-increasing...
7397200 Device for the control of fluorescent lamps in a lighting arrangement  
The invention relates to a device for the control of fluorescent lamps in a lighting arrangement that comprises at least one such fluorescent lamp, wherein for each fluorescent lamp the device has...
7397199 Discharge lamp lighting device  
Output of a chopper circuit is converted to a rectangular wave by a push-pull circuit, and is provided to a step-up transformer. When a switch is turned on, the control voltage of the chopper...
Matches 1 - 50 out of 2254 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 >