Plural Load Device Systems Patents (Class 315/250)
  • Publication number: 20100060182
    Abstract: A low THD lighting system is disclosed. The lighting system includes a first lighting module and a second lighting module connected parallel to the first lighting module. During each AC cycle the first lighting module conducts current for a first portion of the cycle and the second lighting module conducts current for a second portion of the cycle. When combined, the total current drawn from the power source substantially tracks the shape of the applied AC voltage. Accordingly, there is minimal distortion, and low total harmonic distortion level is achieved.
    Type: Application
    Filed: May 28, 2009
    Publication date: March 11, 2010
    Inventor: Thomas Stack
  • Publication number: 20100052558
    Abstract: Disclosed are a backlight assembly, a driving method thereof and a display apparatus. The backlight assembly includes: a light source unit which has a plurality of point light source strings; a plurality of driving elements which are connected to the plurality of point light source strings; a detector which detects currents flowing in the plurality of point light source strings; and a light source driver which generates driving pulses to drive the plurality of driving elements in a linear operating region, adjusts duty ratios of the driving pulses based on at least one of the detected currents so that the currents flowing in the plurality of point light source strings are within a range.
    Type: Application
    Filed: August 28, 2009
    Publication date: March 4, 2010
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Sang-hoon LEE, Joon-hyun YANG, Tae-hoon KIM, Youn-hee KIM
  • Publication number: 20100039042
    Abstract: In a balancer board for a back light device, a plurality of shunt coils configured to transfer power from an inverter to a plurality of fluorescent tubes arrayed in a line are arrayed in a line in a direction which is the same as the direction in which the fluorescent tubes are arrayed, and respective patterns formed on front and rear surfaces of the balancer board so as to supply the power from the inverter to each of the plurality of shunt coils are formed such that the pattern formed on one surface is located apart from the pattern formed on the other surface with a predetermined distance left therebetween while mutually intersecting three-dimensionally in respective planes.
    Type: Application
    Filed: August 7, 2009
    Publication date: February 18, 2010
    Inventor: Seiichi Tsunoda
  • Publication number: 20100019685
    Abstract: A dielectric barrier discharge lamp lighting apparatus includes a plurality of dielectric barrier discharge lamps each of which includes an internal electrode sealed at one end, an external electrode arranged outside of a discharge space of the dielectric barrier discharge lamps, and a ballast circuit for applying a high voltage at high frequency between the internal electrode and the external electrode to operate the plurality of dielectric barrier discharge lamps. The plurality of lamps are arranged in parallel, and arranged so that the position of the internal electrode of each dielectric barrier discharge lamp is at different side in the adjacent dielectric barrier discharge lamps, and at the same sides in every other dielectric barrier discharge lamp. The ballast circuit applies voltages at high frequency with difference in phase to adjacent dielectric barrier discharge lamps.
    Type: Application
    Filed: September 7, 2007
    Publication date: January 28, 2010
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Satoshi Kominami, Kiyoshi Hashimotodani
  • Publication number: 20100014019
    Abstract: Embodiment relate to a lamp driving device and a liquid crystal display device having the same. The embodiments include a plurality of lamps having first and second electrodes, an inverter substrate supplying a high voltage alternating current to at least one of the first and second electrodes of the lamps, a plurality of capacitors connected to the first and second electrodes of the lamps, and a board capacitor connected to at least one of the capacitors.
    Type: Application
    Filed: May 10, 2007
    Publication date: January 21, 2010
    Inventor: Chang Sun Yun
  • Publication number: 20090322241
    Abstract: An alternating current (AC) driven light emitting device includes a substrate, K number of first light emitting diode (LED) cells arranged in a row on a top surface of the substrate, where K is an integer satisfying K?3, K number of second LED cells arranged in a row parallel to the row of the first LED cells on the top surface of the substrate, and (K?1) number of third LED cells arranged in a row between the respective rows of the first and second LED cells on the top surface of the substrate. The AC driven light emitting device has a connection structure between LED cells to be operable at an AC.
    Type: Application
    Filed: November 5, 2008
    Publication date: December 31, 2009
    Inventors: Grigory Onushkin, Gil Han Park, Jung Ja Yang, Young Jin Lee
  • Publication number: 20090289571
    Abstract: A computing device is disclosed. The computing device includes a housing having an illuminable portion. The computing device also includes a light device disposed inside the housing. The light device is configured to illuminate the illuminable portion.
    Type: Application
    Filed: July 31, 2009
    Publication date: November 26, 2009
    Applicant: APPLE INC.
    Inventors: Duncan R. KERR, Steve P. HOTELLING
  • Publication number: 20090284960
    Abstract: The LED projection night light for night time or dark area use including plug-in wall outlet night light or direct current operated night light with projection features to project the image, message, data, logo, time on ceiling, walls, floor, desired surface. The said LED night light incorporated with optics means may selected from group combination from optics-lens, slides, openings, cut-outs, transparent material piece, translucent material piece, telescope assembly, housing-member, slide-film, slide-disc, elastic-member, tilt-means, rotating-means, adjust-means, roller-means, mechanic-means, extend-means, convex lens, concave lens, with precision optics calculation and optics design to make the said desire image, message, data, logo, time project to ceiling, walls, floor, or desired surface to be seen by viewer. The LED light has interchangeable power source arrangement for AC powered sealed-unit or DC powered battery-pack.
    Type: Application
    Filed: December 30, 2008
    Publication date: November 19, 2009
    Inventor: Tseng-Lu Chien
  • Publication number: 20090267523
    Abstract: A light sheet module includes a light sheet having LEDs on a substrate and a driver circuit for the LEDs. The driver circuit includes a first control loop and a second control loop. The first loop contains TRIACS for regulating current from an external AC power source to the LEDs in response to trigger signals. A constant current circuit receives a command signal indicative of a target current in the LEDs, and generates the trigger signals. Current feedback circuitry generates a current feedback signal indicative of the actual current in the LEDs. The constant current circuit responds to the current feedback circuitry and adjusts the trigger signals so that the actual current in the LEDs more closely approaches the target current. The second control loop contains a Driver controller that generates the command signal and that is responsive to an input device for the Driver controller.
    Type: Application
    Filed: April 23, 2009
    Publication date: October 29, 2009
    Applicant: Articulated Technologies, LLC
    Inventor: Ray Phillips
  • Publication number: 20090267530
    Abstract: A backlight module includes a light-emitting unit, and a controller to receive a first control signal and generate a second control signal to control the light-emitting unit. The controller controls a frequency of the second control signal according to a duty cycle of the first control signal.
    Type: Application
    Filed: April 22, 2009
    Publication date: October 29, 2009
    Applicant: Chi Mei Optoelectronics Corporation
    Inventors: Cheng-Feng Yang, Cheng-I Wu, Shih-Pin Huang
  • Publication number: 20090261747
    Abstract: The present invention is directed to an apparatus that drives a lighting system with multiple lamps. A phase shift mechanism is produced either by a digital method, an analog method, or a mixture of the two methods. In a digital method, phase shifts are generated by digital circuits comprising counters, a divider, an adder, and a comparator. The digital circuits analyze the signal and use the necessary information to form a series of phased driving signals. In an analog method, phase shifts are generated by analog circuits comprising ramp waveform generators, comparators, and at least one shot generator. Also, an apparatus for driving a lighting system with multiple lamps can be realized by mixing the two methods mentioned above.
    Type: Application
    Filed: July 1, 2009
    Publication date: October 22, 2009
    Applicant: HIMAX TECHNOLOGIES LIMITED
    Inventors: Shwang-Shi Bai, Yu-Pei Huang, Shen-Yao Liang
  • Publication number: 20090261746
    Abstract: A method and circuit to control the intensity of lights, illumination fixtures, and displays using pulses of a fixed duration and a fixed frequency (FD/FF) is provided. In particular, the method may be used to control one more light sources. By varying the number of pulses in a control burst, the total current flowing through the light source may be precisely controlled providing greater accuracy than other methods, such as, for example, PWM or variable pulse frequency. The FD/FF technique may be used in conjunction with any number of light sources, and finds particular application in LED displays and for any type of LED illumination fixture.
    Type: Application
    Filed: May 15, 2009
    Publication date: October 22, 2009
    Applicant: LSI INDUSTRIES, INC.
    Inventors: Bassam D. Jalbout, Brian Wong
  • Publication number: 20090261748
    Abstract: A driver circuit produces variable current output for an LED lighting system providing improved dimming capability and greater power efficiency when responding to industry standard lighting dimmers, through the use of an input voltage monitoring circuit which variably controls the current output of a switching regulator. Output current modulation methods such as analog, PWM, Pulse Frequency Modulation, or other digital modulation, and combination or hybrid methods such as that disclosed in U.S. Pat. No. 7,088,059 B2 may be employed. The current invention marries such output modulation techniques with a control method which is derived through intelligent monitoring of the input voltage waveform. The circuit and method described is adapted to higher current applications such as LED lighting systems using the latest high-power LEDs.
    Type: Application
    Filed: April 14, 2009
    Publication date: October 22, 2009
    Inventors: Steven McKinney, Isay Goltman
  • Publication number: 20090218954
    Abstract: A sequential burst mode regulation system to deliver power to a plurality of loads. In the exemplary embodiments, the system of the present invention generates a plurality of phased pulse width modulated signals from a single pulse width modulated signal, where each of the phased signals regulates power to a respective load. Exemplary circuitry includes a PWM signal generator, and a phase delay array that receives a PWM signal and generates a plurality of phased PWM signals which are used to regulate power to respective loads. A frequency selector circuit can be provided that sets the frequency of the PWM signal using a fixed or variable frequency reference signal.
    Type: Application
    Filed: January 12, 2009
    Publication date: September 3, 2009
    Inventors: Yung-Lin Lin, Yu-Cheng Chang, Bingwei Yao
  • Publication number: 20090212712
    Abstract: The invention relates to an electronic ballast for a lamp, supplied with electrical energy from a power source, different to the mains AC network, comprising at least one electronic switch element for conversion of the supplied electrical power. According to the invention, a microcontroller controls the electronic switch element.
    Type: Application
    Filed: May 15, 2006
    Publication date: August 27, 2009
    Applicant: OSRAM GESELLSCHAFT MIT BESCHRAENKTER HAFTUNG
    Inventor: Helmut Endres
  • Publication number: 20090206767
    Abstract: An apparatus and method for driving a lamp are provided. In one embodiment, an inverter having four switching elements is split into two inverter arms that are deployed at separate terminals of a floating lamp structure to achieve even light output. A controller drives both inverter arms such that power switching lines do not cross the floating lamp structure. In one embodiment, the controller adjusts the brightness of the lamp structure by adjusting the phase difference between outputs of a first inverter arm relative to a second inverter arm. In one embodiment, the controller adjusts the brightness by symmetrically pulse width modulating the outputs of the first inverter arm and the second inverter arm.
    Type: Application
    Filed: April 27, 2009
    Publication date: August 20, 2009
    Applicant: MICROSEMI CORPORATION
    Inventor: XIAOPING JIN
  • Publication number: 20090204239
    Abstract: Embodiments of the disclosure provide a system for selecting a color show generated by LED landscape, pool, and/or spa lights. The system can include a faceplate indicating the color shows available to select from. The faceplate includes a selector positioned to select one of the color shows. The system includes a microcontroller in communication with the selector and a triac circuit in communication with the microcontroller. The microcontroller controls the LED landscape, pool, and/or spa lights using the triac circuit in response to the position of the selector.
    Type: Application
    Filed: October 29, 2008
    Publication date: August 13, 2009
    Inventors: Robert J. Netzel, SR., Daniel A. Armstrong, Louis F. Teran, Jeffrey S. Barsamian, Abhinay Agarwal, Santanu Roy, Dennis C. Dunn
  • Publication number: 20090179579
    Abstract: The present invention uses the mutually series connected resistive, or inductive, or capacitive impedance to divide the voltage of bi-directional power source, thereby using the divided power of the impedance component to drive the bi-directional conducting light emitting diode in parallel connection at the two ends of the impedance.
    Type: Application
    Filed: January 12, 2009
    Publication date: July 16, 2009
    Inventor: Tai-Her YANG
  • Publication number: 20090179578
    Abstract: The present invention comprises of a first impedance constituted by the capacitive impedance and a second impedance constituted by the inductive impedance, wherein the first and second impedance after series connection appears in the series resonance status to generate a bi-directional divided power in series resonance to drive the bi-directional conducting light emitting diode parallel connected with the first or second impedance.
    Type: Application
    Filed: January 12, 2009
    Publication date: July 16, 2009
    Inventor: Tai-Her YANG
  • Publication number: 20090174338
    Abstract: A LED drive circuit equipped with oscillator 18, up/down counter 20, and DAC 22 in order to drive multiple LEDs 10(1)-10(m) in a block. Up/down counter 20 carries out count-up/down operations in sync with clock CLK sent from oscillator 18 during the ramping up/down of pulse-lighting of the LEDs. DAC 22 converts counter count value DN into analog voltage signal VDAC and supplies it to the gate terminal of NMOS transistor 14 via low-pass filter 28 and buffer amplifier 24.
    Type: Application
    Filed: November 25, 2008
    Publication date: July 9, 2009
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Yasunori Muramatsu
  • Publication number: 20090174337
    Abstract: An AC-driven LED circuit 10 includes a first parallel circuit 12 having a first branch 14 and a second branch 16 which connect at first and second common point 18, 20. The common points 18, 20 provide input and output for an AC driving current from a driver of the circuit. The first branch 14 has a first LED 26 and a second LED 28, the first LED 26 being connected to the second LED 28 in opposing series relationship with the inputs of the first and second LEDs 26, 28 defining a first branch junction 34. A second branch 16 has a third LED 30 and a fourth LED 32, the third LED 30 is connected to the fourth LED 32 in opposing series relationship with the outputs of the third and fourth LEDs 30, 32 defining a second branch junction 36. Improvement in performance and scalability is provided by adding n diodes to a given parallel circuit and x cross connecting circuit branch diodes (40, 44) and providing one or more parallel circuits (15) in series and or parallel.
    Type: Application
    Filed: October 6, 2008
    Publication date: July 9, 2009
    Applicant: LYNK LABS, INC.
    Inventors: Michael Miskin, Robert L. Kottrisch
  • Publication number: 20090167202
    Abstract: An AC LED package and circuits are disclosed along with an AC LED driver. The AC LED circuit may include as few as one LED or an array of anti-parallel LEDs driven with AC power sources and AC LED drivers at various voltages and frequencies. The AC LEDs are pre-packaged in various forms and materials and designed for mains or high frequency coupling in various forms to AC power sources, inverter type drivers or packages. The AC LED driver is a fixed frequency driver that provides a relatively constant voltage output to different size loads within the wattage limitation of the driver and in some cases is a direct mains power source.
    Type: Application
    Filed: February 3, 2009
    Publication date: July 2, 2009
    Applicant: LYNK LABS, INC.
    Inventors: Michael Miskin, James N. Anderson
  • Publication number: 20090153068
    Abstract: A backlight assembly includes a light-generating unit and an inverter. The light-generating unit includes a first U-shaped lamp and a second U-shaped lamp parallel with each other. Electrodes of the first and second U-shaped lamps are disposed at one side of the light-generating unit. The inverter includes a multi-output transformer, a first output terminal and a second output terminal. The multi-output transformer generates a first driving voltage and a second driving voltage having a phase opposite to a phase of the first driving voltage. The first and second output terminals electrically connect the first and second U-shaped lamps with the multi-output transformer. The multi-output transformer applies the first and second driving voltages to the first and second U-shaped lamps via the first and second output terminals.
    Type: Application
    Filed: November 19, 2008
    Publication date: June 18, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Ju-Sung CHO, Moon-shik KANG, Young-Sup KWON
  • Publication number: 20090140660
    Abstract: A light-emitting diode array is driven by a digital control. The digital control modulates the pulse width of pulses applied to the light-emitting diode. The intensity of the output is controlled by controlling the width of pulses applied to the light-emitting diode. Since light-emitting diodes have very low inertial energy, this system can be rapidly turned on and turned off. The output is integrated to produce a uniform output.
    Type: Application
    Filed: November 21, 2008
    Publication date: June 4, 2009
    Applicant: Aptina Imaging Corporation
    Inventors: Eric R. Fossum, Grzegorz M. Waligorski
  • Publication number: 20090096382
    Abstract: A drive control circuit sends out pulse signals of various pulse signals so as to control the light emission amount and luminance of LEDs by gradually increasing and decreasing the pulse width in predetermined cycles during predetermined periods based on parameters supplied from an LED drive controller that determine a first emission control processing period, a second emission control processing period, first to fourth slope periods and the like. The tone of an emitted color realized by a plurality of LEDs is controlled by synchronizing the periods of time of light emission control processings.
    Type: Application
    Filed: December 15, 2008
    Publication date: April 16, 2009
    Applicant: ROHM CO., LTD.
    Inventors: Isao YAMAMOTO, Tomoyuki ITO, Hiroyuki IWAKI
  • Publication number: 20090091268
    Abstract: A method of feeding electric power to an LED (4) in an airfield lighting unit (7). The method comprises the steps of: feeding a constant alternating current (Is) to a rectifier (40), rectifying the alternating current (Is) to a rectified current (Ir), pulse width modulating the rectified current (Ir), charging a capacitor (43) with the pulse width modulated rectified current (Ir), and feeding the LED (4) with power from the capacitor (43).
    Type: Application
    Filed: September 29, 2008
    Publication date: April 9, 2009
    Applicant: SAFEGATE INTERNATIONAL AB
    Inventors: Johan FORSSEN, Ola Hakanson
  • Publication number: 20090091269
    Abstract: The HIGH FREQUENCY PULSED SUPPLY FOR DISCHARGE LAMPS describes electronic converters for discharge lamps with high frequency pulsed current stabilization. A voltage inverter is employed either in a Full-Bridge configuration using peak current control or in a Half-Bridge configuration with a capacitive element. These converters allow the luminous intensity of the lamp to vary (dimming), as well as the frequency of the pulses over a wide frequency range, avoiding acoustic resonance to appear; they also allow a low frequency power variation, aiming to improve the color rendering index and correlated color temperature properties of the light emitted by certain types of discharge lamps, such as the high pressure sodium lamps. The converters present a significant reduction in the volume of the power circuit due to the removal of the magnetic element, being even more attractive as the power of the lamp increases.
    Type: Application
    Filed: April 4, 2007
    Publication date: April 9, 2009
    Inventors: Arnoldo Jose Perin, Joao Vilela, JR.
  • Publication number: 20090021178
    Abstract: The present invention is directed to a drive apparatus for a backlight unit (20) in which plural LED (Light Emitting Diode) elements are cascade-connected every three primary colors, which comprises a signal generating unit (44) for generating a signal having an arbitrary amplitude, an adjustment unit (50) for adjusting light emission quantities of groups of LED elements (30) on the basis of the signal which has been generated by the signal generating unit (44), a voltage applying unit (41) for applying a predetermined voltage every the groups of LED elements (30), light emission quantity detecting units (33) for detecting quantities of rays of light which have been emitted from the groups of LED elements (30), calorific value detecting units (32) for detecting calorific values emitted from the groups of LED elements in accordance with the voltage which has been applied to the voltage applying unit (41), and a control unit (50) for controlling the signal generating unit (44) on the basis of light emission qua
    Type: Application
    Filed: July 8, 2005
    Publication date: January 22, 2009
    Inventors: Norimasa Furukawa, Hiroaki Ichikawa, Kenichi Kikuchi
  • Publication number: 20090015174
    Abstract: A light source apparatus and a driving apparatus thereof are provided. The driving apparatus includes a first node, a second node, a clock synchronization unit, a control unit, a switch unit, and a feedback unit. The driving apparatus receives an AC voltage through the first and the second nodes. The clock synchronization unit converts the AC voltage into a clock synchronization signal. The control unit converts a preset brightness value into a driving current, outputs an adjusting signal according to a timing of the clock synchronization signal, and modulates a pulse width of the adjusting signal according a feedback signal. The switch unit determines whether or not the AC voltage is provided to the light source module according to a control of the adjusting signal. The feedback unit detects a load state of the light source module, and outputs the feedback signal to the control unit according a detection result.
    Type: Application
    Filed: July 31, 2007
    Publication date: January 15, 2009
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Jui-Feng Huang, Lung-Pin Chung
  • Publication number: 20090009101
    Abstract: The present invention provides a stacked organic light emitting device, comprising a first conductive layer, at least one intermediate conductive layer and a second conductive layer, and light emitting units disposed between the conductive layers, wherein at least two non-neighboring conductive layers among the conductive layers are conductive layers belonging to Group 1 such that they are electrically connected with each other to a common potential; at least one non-neighboring conductive layer among the conductive layers which are not electrically connected with the conductive layers belonging to Group 1 to a common potential are conductive layers belonging to Group 2 such that they are electrically connected with each other to a common potential; and the conductive layers belonging to Group 1 and the conductive layers belonging to Group 2 are connected with each other via a voltage regulator for alternately applying a positive voltage and a negative voltage.
    Type: Application
    Filed: January 17, 2007
    Publication date: January 8, 2009
    Inventors: Min-Soo Kang, Jeoung-Kwen Noh, Jung-Hyoung Lee
  • Publication number: 20090009102
    Abstract: It is presented a lighting device comprising: at least one alternating current source configured to provide alternating current of at least a first and a second frequency, at least one light source, at least one impedance unit connected to the light source, affecting a first current from the at least one alternating current source to flow through the at least one light source, wherein an impedance of the impedance unit is configured to be frequency controlled, such that when the alternating current is of the first frequency the first current is relatively high and when the alternating current is of the second frequency the first current is relatively low. A corresponding display device, television device and method are also presented.
    Type: Application
    Filed: January 31, 2007
    Publication date: January 8, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Henricus Marius Joseph Kahlman, Renatus Willem Clemens Van Der Veeken
  • Publication number: 20080315784
    Abstract: The present invention provides an LED lamp structure, including a circuit board, a circular coil, and a lamp housing. The circuit board has one or more LED light bulb mounted thereon, and the circular coil includes an iron core, a primary winding and a secondary winding, wherein the primary winding of the circular coil is connected with the lamp housing for conducting an AC power, and then, the secondary winding, which is connected with the circuit board, is induced to produce a DC power for transmitting to the circuit board, thereby lighting up the LED light bulb on the circuit board.
    Type: Application
    Filed: June 25, 2007
    Publication date: December 25, 2008
    Inventor: Jui-Kai Tseng
  • Publication number: 20080284347
    Abstract: A lighting control system is operable to be coupled to a security system and is pre-programmed such that the control devices of the lighting control system behave out-of-box in a predetermined manner in response to the security system. The lighting control system comprises a contact closure input that is operable to be simultaneously coupled to both a momentary contact closure output and a maintained contact closure output of the security system. Preferably, the lighting control system enters a first mode of operation when the contact closure input detects a closure, enters a second mode of operation if the contact closure input continues to detect the closure after a predetermined amount of time, and enters a third mode of operation if the contact closure input no longer closed. Accordingly, the lighting control system is responsive to either the momentary contact closure output or the maintained contact closure output.
    Type: Application
    Filed: May 17, 2007
    Publication date: November 20, 2008
    Inventor: Daniel Curtis Raneri
  • Publication number: 20080278093
    Abstract: An exemplary backlight module (20) includes a plurality of light units (22) disposed in parallel. Each light unit includes two opposite electrodes (221, 222). Two alternating current (AC) voltages having 180° phase difference and a same frequency are respectively applied to the two opposite electrodes, and two AC voltages respectively applied to the two electrodes, at a same side, of two adjacent light units, have 180° phase difference and a same frequency.
    Type: Application
    Filed: May 12, 2008
    Publication date: November 13, 2008
    Inventor: Sha Feng
  • Patent number: 7439945
    Abstract: A Light-Emitting Diode (LED) driver circuit is disclosed that controls the brightness of light generated by a LED that is coupled between a first terminal and a second terminal in response to a user supplied brightness control signal. A constant current source generates a constant current that is supplied to the LED and to a shunt circuit, which his connected in parallel with the LED. A brightness control circuit generates a pulse signal having a duty cycle that is proportional to the brightness control signal, and controls the shunt circuit such that, when said pulse signal is high, the constant current is passed through the shunt circuit and the LED is turned off, and when the pulse signal is low, the constant current is passed through the LED. The duty cycle of the brightness control signal is adjusted to adjust the LED's brightness, while the LED color remains constant.
    Type: Grant
    Filed: October 1, 2007
    Date of Patent: October 21, 2008
    Assignee: Micrel, Incorporated
    Inventors: Thruston Awalt, Qi Deng
  • Publication number: 20080218098
    Abstract: The present invention relates to a light emitting device. The light emitting device according to the present invention comprises a light emitting cell block having a plurality of light emitting cells; and a bridge rectifying circuit connected to input and output terminals of the light emitting cell block, wherein the bridge rectifying circuit includes a plurality of diodes between nodes. In manufacturing an AC light emitting device with a bridge rectifying circuit built therein, the present invention can provide a light emitting device capable of enhancing the reliability and luminance of the light emitting device by setting the size of diodes of the bridge rectifying circuit to be a certain size and controlling the number thereof.
    Type: Application
    Filed: December 5, 2006
    Publication date: September 11, 2008
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventors: Jae Ho Lee, Yeo Jin Yoon, Eu Jin Hwang, Lacroix Yves
  • Publication number: 20080218093
    Abstract: A structure of light-emitting diode (LED) dies having an AC loop (a structure of AC LED dies), which is formed with at least one unit of AC LED micro-dies disposed on a chip. The unit of AC LED micro-dies comprises two LED micro-dies arranged in mutually reverse orientations and connected with each other in parallel, to which an AC power supply may be applied so that the LED unit may continuously emit light in response to a positive-half wave voltage and a negative-half wave voltage in the AC power supply. Since each AC LED micro-die is operated forwardly, the structure of AC LED dies also provides protection from electrical static charge (ESD) and may operate under a high voltage.
    Type: Application
    Filed: May 9, 2008
    Publication date: September 11, 2008
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Ming-Te Lin, Fei-Chang Hwang, Chia-Tai Kuo
  • Patent number: 7423389
    Abstract: An LED driving device comprises a PWM IC including an RT/CT terminal operated by a power voltage and generating and outputting a sawtooth wave voltage of a predetermined frequency, a COMP terminal to which a comparison voltage compared with the sawtooth wave voltage is inputted, and an output terminal generating and outputting a pulse signal turned off in a section in which a level of the sawtooth wave voltage is higher than a level of the comparison voltage and turned on in a section in which the level of the sawtooth voltage is lower than the level of the comparison voltage. The LED driving device sets up the comparison voltage inputted to the COMP terminal of the PWM IC to be 0 when an error voltage corresponding to a difference between a both end voltage of an LED array and a predetermined reference voltage is less than a predetermined level.
    Type: Grant
    Filed: April 23, 2007
    Date of Patent: September 9, 2008
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventor: Sang Yun Lee
  • Publication number: 20080211421
    Abstract: Disclosed is an improved light-emitting device for an AC power operation. A conventional light emitting device employs an AC light-emitting diode having arrays of light emitting cells connected in reverse parallel. The arrays in the prior art alternately repeat on/off in response to a phase change of an AC power source, resulting in short light emission time during a ½ cycle and the occurrence of a flicker effect. An AC light-emitting device according to the present invention employs a variety of means by which light emission time is prolonged during a ½ cycle in response to a phase change of an AC power source and a flicker effect can be reduced. For example, the means may be switching blocks respectively connected to nodes between the light emitting cells, switching blocks connected to a plurality of arrays, or a delay phosphor.
    Type: Application
    Filed: May 9, 2006
    Publication date: September 4, 2008
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventors: Chung Hoon Lee, James S. Speck, Hong San Kim, Jae Jo Kim, Sung Han Kim, Jae Ho Lee
  • Publication number: 20080191637
    Abstract: A simple method and apparatus are described for controlling two or more electrical devices. An encoder receives an alternating current (AC) voltage waveform and converts the AC voltage waveform to a modified voltage waveform selected according to a control input. A decoder located near the electrical devices receives the modified voltage waveform and either energies or deenergizes each of the electrical devices, depending upon the modified voltage waveform. Energized electrical devices receive energy from the modified voltage waveform. The modified voltage waveform both selects electrical devices to be energized and provides power to the energized electrical devices.
    Type: Application
    Filed: September 24, 2004
    Publication date: August 14, 2008
    Inventor: Peter R. Pettler
  • Publication number: 20080164826
    Abstract: Methods and apparatus for simulating resistive loads, and facilitating series, parallel, and/or series-parallel connections of multiple loads to draw operating power. Current-to-voltage characteristics of loads are altered in a predetermined manner so as to facilitate a predictable and/or desirable behavior of multiple loads drawing power from a power source. Exemplary loads include LED-based light sources and LED-based lighting units. Altered current-to-voltage characteristics may cause a load to appear as a substantially linear or resistive element to the power source, at least over some operating range. In connections of multiple such loads, the voltage across each load is relatively more predictable. In one example, a series connection of multiple loads with altered current-to-voltage characteristics may be operated from a line voltage without requiring a transformer.
    Type: Application
    Filed: August 9, 2007
    Publication date: July 10, 2008
    Applicant: Color Kinetics Incorporated
    Inventor: Ihor A. Lys
  • Publication number: 20080164827
    Abstract: Methods and apparatus for simulating resistive loads, and facilitating series, parallel, and/or series-parallel connections of multiple loads to draw operating power. Current-to-voltage characteristics of loads are altered in a predetermined manner so as to facilitate a predictable and/or desirable behavior of multiple loads drawing power from a power source. Exemplary loads include LED-based light sources and LED-based lighting units. Altered current-to-voltage characteristics may cause a load to appear as a substantially linear or resistive element to the power source, at least over some operating range. In connections of multiple such loads, the voltage across each load is relatively more predictable. In one example, a series connection of multiple loads with altered current-to-voltage characteristics may be operated from a line voltage without requiring a transformer.
    Type: Application
    Filed: August 9, 2007
    Publication date: July 10, 2008
    Applicant: Color Kinetics Incorporated
    Inventor: Ihor A. Lys
  • Publication number: 20080136347
    Abstract: A light emitting device and the fabrication method includes forming one or more light emitting modules on a substrate. The light emitting module receives an alternating current input and has at least two micro diodes. Each micro diode has at least two active layers and is electrically connected by a conductive structure so as to allow the active layers of the micro diodes to alternately emit light during positive and negative cycles of the alternating-current input.
    Type: Application
    Filed: January 28, 2008
    Publication date: June 12, 2008
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Ming-Te LIN, Hsi-Hsuan YEN, Wen-Yung YEH, Ming-Yao LIN, Sheng-Pan HUANG
  • Publication number: 20080116821
    Abstract: The presented circuit makes it possible to operate a plurality of gas discharge lamps, particularly cold cathode tubes, at a common voltage source. The uniform distribution of current to all the lamps is achieved without using any magnetic components, but only using semiconductor components.
    Type: Application
    Filed: October 19, 2007
    Publication date: May 22, 2008
    Inventors: Robert Weger, Masaya Yamashita
  • Publication number: 20080042592
    Abstract: The present invention provides a method and apparatus for controlling the thermal gradient and therefore the thermal stress in light-emitting elements in which the light-emitting elements are exposed to temperature gradients caused by varying drive current under operating conditions. The method and apparatus according to the present invention can reduce the thermal stress in a light-emitting element by adaptively determining a drive current transient for a required change in the drive current from a first drive current state to a desired second drive current state, wherein the drive current transient is adaptively determined in order to substantially minimize the change in applied voltage over time, during the transition time period.
    Type: Application
    Filed: August 10, 2007
    Publication date: February 21, 2008
    Inventor: Ian Ashdown
  • Patent number: 7282863
    Abstract: A method and electronic circuit operate a quartz auxiliary lamp lighting lamp and circuit to light a quartz auxiliary lamp at 120 Vac and 50-60 Hz current connected to an electronic HID ballast operating at a frequency of 100 Hz to over 400 kHz and voltages of from 120 Vac, as provided by a multitap transformer and related circuitry.
    Type: Grant
    Filed: July 11, 2005
    Date of Patent: October 16, 2007
    Assignee: Varon Lighting Group, LLC
    Inventors: Glenn Garbowicz, Thomas J. Mayer
  • Patent number: 7215523
    Abstract: An apparatus for protecting an integrated circuit is applied to an electrical apparatus having a control unit. The control unit is used for controlling the integrated circuit and the protecting apparatus. The protecting apparatus includes a power input terminal, a power output terminal, and a control terminal. The power input terminal is used for receiving a power, and the power output terminal is used for outputting the power to the integrated circuit. The control terminal is used for receiving a control voltage of the control unit. When the control unit is at the power on mode, the control unit outputs the control voltage of a first level to prevent the power being input to the integrated circuit. Over a predetermined period of time, the control unit outputs the control voltage of a second level, so that the power can be input to the integrated through the protecting apparatus.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: May 8, 2007
    Assignee: Benq Corporation
    Inventor: Chih-Yuan Lin
  • Patent number: 7164237
    Abstract: A DC-AC converter in a half bridge configuration is used for operation with high pressure discharge lamps as well as low pressure discharge lamps. The converter consists in two switches (T1-T2) serially connected through a first series of diodes (D1, D2) and a second series of diodes (D3,D4) to which at their middle points (N1, N2) a first and a second lamp loads (L1,L2,LA1,LA2) are connected. Furthermore, the second terminals of the lamp loads are connected to the middle point of a series of capacitors (C3,C4) which are also connected to the terminals (Ki,K2) of the supply voltage source. The converter includes also four diodes (D5,D6,D7,D8) which shunt the switches (T1,T2) and their respective series of diodes (D1,D2,D3,D4). The switches (T1,T2) are controlled by a controller (CC) which renders alternatively conductive at low frequency the two switches (Ti,T2).
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: January 16, 2007
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Dolf Henricus Jozef Van Casteren
  • Patent number: 7009347
    Abstract: An embodiment of the present invention pertains to a multiple discharge load electronic ballast system, including a distribution bus and a plurality of electronic ballasts. The distribution bus has a nominal distribution power rating. The plurality of electronic ballasts are operatively coupled to the distribution bus. A respective electronic ballast comprises adaptations for DC voltage control and an alternating current (AC) output, and has a maximum ballast power rating. A sum of the maximum ballast power ratings of the plurality of electronic ballasts is greater than the nominal distribution power rating of the distribution bus.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: March 7, 2006
    Assignee: Nicollet Technologies Corporation
    Inventor: Christopher P. Henze
  • Patent number: 6646391
    Abstract: A light source device for a dielectric barrier discharge lamp including a dielectric barrier discharge lamp having a discharge space, the discharge space being filled with a discharge gas which produces excimers by a dielectric barrier discharge; first and second electrodes, a dielectric positioned between at least one of the first and second electrodes for inducing a discharge in the discharge gas, and a feed device for applying an essentially periodic AC high voltage to the first and second electrodes of the dielectric barrier discharge lamp. The feed device includes a setting mechanism for adjusting both the control frequency of the essentially periodic AC high voltage and the amplitude of the essentially periodic AC high voltage in accordance with a set control frequency.
    Type: Grant
    Filed: January 15, 2002
    Date of Patent: November 11, 2003
    Assignee: Ushiodenki Kabushiki Kaisha
    Inventors: Masashi Okamoto, Takahiro Hiraoka, Toshio Okamoto