Transformer In The Supply Circuit Patents (Class 315/276)
  • Patent number: 7656099
    Abstract: The invention relates to a circuit arrangement for operating high pressure discharge lamps and corresponding operating method, whereby the input voltage for the pulsed trigger device is increased by means of a series resonance loop (L3, C4), of a cascade circuit, or a symmetrical voltage doubling circuit.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: February 2, 2010
    Assignee: Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH
    Inventors: Günther Hirschmann, Daniel Lerchegger, Bernhard Sieβegger
  • Patent number: 7652435
    Abstract: A lamp driving circuit includes: a first voltage generator which receives a direct current power voltage and outputs a first square wave voltage in response to a first switching signal and a second switching signal having a phase inverted with respect to the first switching signal; a second voltage generator which outputs a second square wave voltage in response to a third switching signal having a phase shifted by a predetermined time with respect to the phase of the first switching signal and a fourth switching signal having a phase inverted with respect to the phase of the third switching signal; and a transformer which receives the first square wave voltage and the second square wave voltage and boosts a first driving voltage defined by an electric potential difference therebetween to a second driving voltage and applies the second driving voltage to a lamp.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: January 26, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Moon-Shik Kang
  • Patent number: 7646279
    Abstract: Apparatus for supplying energy to a load, comprises a power supply unit (102) e.g. a switched mode electronic transformer or electronic ballast having an input for receiving current at mains frequency and a means for stepping-up said mains frequency to a higher frequency e.g. 30-50 kHz and an output for delivering energy at the higher frequency. A two part connector (108) has a first core portion (106) that has a primary winding (104) connected to the output of the power supply unit and a mating second core portion (112) that has a secondary winding (110) for delivery of energy to a load (114), the core portions being of a high resistivity material, e.g. a ferrite having a resistivity of at least 104 ?cm. The apparatus may be used to power e.g. low voltage halogen or other incandescent lighting, fluorescent lighting, or an electric motor, a power supply for a computer, radio, television or like electronic device, a heater or the like.
    Type: Grant
    Filed: May 4, 2004
    Date of Patent: January 12, 2010
    Inventors: George A. Limpkin, Simon G. Rozenberg
  • Publication number: 20100001655
    Abstract: Disclosed is an inverter circuit. The inverter circuit comprises a transformer comprising a primary coil and a secondary coil wound at a predetermined turn ratio, a first switch circuit comprising first and second switch devices commonly connected with a first end of the primary coil of the transformer, a second switch circuit comprising third and fourth switch devices commonly connected with a second end of the primary coil of the transformer, and a third switch circuit comprising fifth and sixth switch devices commonly connected with a part of the primary coil of the transformer.
    Type: Application
    Filed: April 17, 2008
    Publication date: January 7, 2010
    Inventor: Jae Hyun Han
  • Patent number: 7642763
    Abstract: An exemplary switching power supply circuit (2) includes a power source (20), a pulse width modulation (PWM) circuit (21), a first switching circuit (22), a second switching circuit (23), a first transformer (25), and a second transformer (26). The first switching circuit includes a first transistor (221) and a second transistor (222). The second switching circuit includes a third transistor (231) and a fourth transistor (232). The first transformer includes a first primary winding (251) and a second primary winding (252), and the second transformer includes a third primary winding (261) and a fourth primary winding (262). The switching circuits are controlled by pulse signals from the PWM circuit. When the first and third transistors are switched on, the power source, the first primary winding, and the first transistor form a first closed loop. The power source, the third primary winding, and the third transistor form a second closed loop.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: January 5, 2010
    Assignees: Innocom Technology (Shenzhen) Co., Ltd., Innolux Display Corp.
    Inventors: Jian-Hui Lu, Tong Zhou
  • Patent number: 7642726
    Abstract: A power supply apparatus includes an inverter controller, a power transforming part and a connecting part. The power transforming part converts a direct current supplied from the inverter controller into an alternating current to output first and second polarity currents. The connecting part outputs the first and second polarity currents to first and second end portions of a load through first and second terminals, respectively and has a third terminal to receive a sensed signal in response to the first or second polarity currents so as to output the sensed signal. The first terminal is spaced apart from the second terminal by a first insulating distance, and the third terminal is spaced apart from the first or second terminals adjacent to the third terminal by a second insulating distance. Therefore, the sensed signal is independent of the output power, thereby increasing the sensing efficiency.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: January 5, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hyeong-Suk Yoo, Moon-Shik Kang
  • Publication number: 20090315464
    Abstract: The invention discloses a transformer for a backlight apparatus including a lamp and a detecting unit. The transformer includes a bobbin, a first winding and a second winding. The bobbin has a low-voltage winding region and a high-voltage winding region. The first winding is wound on the high-voltage winding region and is coupled to the lamp. The low-voltage winding region has a first pin, a second pin and a third pin. Firstly, the second winding is wound on the first pin and then wound on the low-voltage winding region for M turns. Next, the second winding is drawn out from the low-voltage winding region, then wound on the second pin, and then drawn back to be wound on the low-voltage winding region for N turns again. Afterwards, the second winding is drawn out again and wound on the third pin, where each of M and N is a nature number. In addition, the third pin is coupled to the detecting unit.
    Type: Application
    Filed: April 1, 2009
    Publication date: December 24, 2009
    Applicant: Darfon Electronics Corp.
    Inventors: Ming Yen Wu, Ching Chang Hsieh, Ming-Chang Ho, Pin Hsuan Chang
  • Publication number: 20090315472
    Abstract: A backlight module positioned on a printed circuit board (PCB) includes a power control circuit, a transformer, and a voltage detection component. The power control circuit outputs power signals. The transformer has a primary winding and at least one secondary winding. The primary winding is connected to the power control circuit and receives the power signals. The voltage detection component is positioned on a high voltage terminal of the secondary winding of the transformer, detecting voltage variations in the high voltage terminal of the secondary winding of the transformer, and outputting the detected voltage variation to the power control circuit. The power control circuit adjusts the output power signals according to the detected voltage variation.
    Type: Application
    Filed: April 2, 2009
    Publication date: December 24, 2009
    Applicant: AMPOWER TECHNOLOGY CO., LTD.
    Inventors: CHI-HSIUNG LEE, HUNG-CHANG LIANG, YU-HSIAO CHAO
  • Patent number: 7635956
    Abstract: A lower-cost and more precise control methodology of regulating the output voltage of a flyback converter from the primary side is provided, which works accurately in either continuous voltage mode (CCM) and discontinuous mode (DCM), and can be applied to most small, medium and high power applications such cell phone chargers, power management in desktop computers and networking equipment, and, generally, to a wide spectrum of power management applications. Two highly integrated semiconductor chips based on this control methodology are also described that require very few components to build a constant voltage flyback converter.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: December 22, 2009
    Assignee: Active-Semi, Inc.
    Inventors: Steven Huynh, Mingliang Chen, Chuan Xiao, Mingfan Yu
  • Patent number: 7635955
    Abstract: A lamp assembly includes a lamp and a lamp driving device. The lamp includes a body and first and second electrodes. The body converts invisible ray generated by a discharge into visible ray, and the electrodes are disposed on the body. The lamp driving device provides the first and second electrodes with first and second driving voltages, respectively, to generate the discharge. The first driving voltage is less than a first critical voltage at which a corona discharge occurs at the first and second electrodes. When the first electrode is electrically connected to a ground, the first critical voltage may be about 1,200 volts. When the second driving voltage has an inverted phase with respect to the first driving voltage, the first critical voltage is about 2,400 volts. An ozone gas may not be generated at the first and second electrodes to prevent the damage of the electrodes.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: December 22, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hyeong-Suk Yoo, Sang-Yu Lee, Seok-Hyun Nam
  • Publication number: 20090309509
    Abstract: In accordance with one embodiment of the present invention, there is provided a switch-mode power supply to generate the heating current for a hot-filament electron-emitting cathode. The power supply directly couples, without an output power transformer, the output from a full-bridge converter that operates at an output frequency in the range from ten Hz to tens of Khz to the output terminals of the power supply. A connection to a reference potential that minimizes the potential fluctuation of the cathode is provided by the center tap on an autotransformer connected across the output terminals, where the conductors in the autotransformer are sized for half of the emission current from the cathode rather than the much larger heating current.
    Type: Application
    Filed: June 11, 2008
    Publication date: December 17, 2009
    Inventors: Steven J. Geissler, James R. Kahn, Harold R. Kaufman
  • Publication number: 20090295304
    Abstract: A ballast with multilateral lead wires is provided for supplying a power for fluorescent lamps. The ballast comprises a lid and a longitudinal container for containing a ballast circuit for processing an input power and generating a lamp power supply to one or more of the lamps. The circuit includes an input connector mounted on an edge of the circuit for receiving input power wires and an output connector mounted on the opposite edge of the circuit from the input connector for connecting one or more sets of output lead wires. The lid is tightly fastened over the container and has two opposite edgewise basins with access openings for the wires to the input and output connectors.
    Type: Application
    Filed: May 28, 2008
    Publication date: December 3, 2009
    Inventor: Kevin Yang
  • Patent number: 7626338
    Abstract: A discharge lamp lighting apparatus includes a transformer unit, a casing for housing the transformer unit, and a circuit board including circuit components. In the casing, the circuit board is joined to the casing and the transformer unit is fixed to the circuit board through a heat conductive member having thermal conductivity of more than 0.1 W/(m·k). Heat produced by the transformer unit is transferred to the casing through the heat conductive member and released through the casing effectively. In the lighting apparatus, therefore, while the transformer unit is arranged relatively close to the circuit components, the heat can be prevented from affecting the circuit components.
    Type: Grant
    Filed: April 11, 2006
    Date of Patent: December 1, 2009
    Assignee: Denso Corporation
    Inventors: Koichi Kato, Yoshitaka Sato
  • Patent number: 7622870
    Abstract: A switching circuit includes a plurality of transistors connected to a primary winding of the transformer and alternately applies an input voltage and a ground voltage to the primary winding according to turning-on and turning-off of each of the transistors. A plurality of capacitors are provided to the respective fluorescent lamps. One ends of the capacitors are commonly connected to a secondary winding of the transformer, and the other ends thereof are connected to the respective fluorescent lamps. A control circuit monitors a current flowing through a predetermined current path among current paths of the entire circuits including an inverter and the fluorescent lamps and performs feedback control of the turning-on and turning-off states of a plurality of the transistors of the switching circuit to adjust supply of switching power to the primary winding of the transformer so that the monitored current can be maintained in a predetermined condition.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: November 24, 2009
    Assignee: Rohm Co., Ltd.
    Inventors: Kenichi Fukumoto, Goang-Woo Nam
  • Patent number: 7619371
    Abstract: Two out-of-phase inverters are used for driving a backlight for large LCD panels. The lamp currents of each inverter are regulated to substantially the same level to ensure the same brightness in the lamps without any current balancing devices. The switching frequencies in both inverters are synchronized and maintained in an out-of-phase condition during operation.
    Type: Grant
    Filed: April 11, 2006
    Date of Patent: November 17, 2009
    Assignee: Monolithic Power Systems, Inc.
    Inventor: Wei Chen
  • Patent number: 7619372
    Abstract: An apparatus includes circuitry that responds to application to its input of an alternating current input signal by producing at its output an output signal suitable for driving an electronic light generating element. The circuitry includes a regulating section that has a magnetic switch and that causes a current flowing through the output to be maintained substantially at a selected value. A different aspect relates to a method for operating circuitry having an input, an output and a magnetic switch. The method includes causing the circuitry to respond to application to its input of an alternating current input signal by producing at its output an output signal suitable for driving an electronic light generating element, where the magnetic switch is used in regulating a current flowing through the output so as to maintain the current substantially at a selected value.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: November 17, 2009
    Assignee: Lighting Science Group Corporation
    Inventor: Paul J. Garrity
  • Patent number: 7615936
    Abstract: An inductive power supply system for providing power to one or more inductively powered devices. The system includes a mechanism for varying the physical distance or the respective orientation between the primary coil and secondary coil to control the amount of power supplied to the inductively powered device. In another aspect, the present invention is directed to an inductive power supply system having a primary coil and a receptacle disposed within the magnetic field generated by the primary coil. One or more inductively powered devices are placed randomly within the receptacle to receive power inductively from the primary coil. The power supply circuit includes circuitry for adjusting the power supplied to the primary coil to optimize operation based on the position and cumulative characteristics of the inductively powered device(s) disposed within the receptacle.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: November 10, 2009
    Assignee: Access Business Group International LLC
    Inventors: David W. Baarman, Stephen J. McPhilliamy, Christopher B. Houghton
  • Publication number: 20090273738
    Abstract: A pulse width modulator generates a PWM signa whose duty ratio is feedback-controlled so that a detection voltage according to a current across a secondary coil of a transformer is brought close to a reference voltage. A logic control unit performs a switching control of the current across the primary coil of the transformer, based on the PWM signal outputted from the pulse width modulator. A first protection circuit detects a circuit failure of an inverter and stops the switching control of the inverter when the circuit failure continues for a predetermined duration of error detection time. A second protection circuit monitors a feedback voltage corresponding to an output voltage of the inverter, and lowers the reference voltage sets the duration of error detection time short when the feedback voltage is lower than a predetermined threshold voltage.
    Type: Application
    Filed: November 21, 2006
    Publication date: November 5, 2009
    Applicant: ROHM CO., LTD.
    Inventor: Kenichi Fukumoto
  • Patent number: 7605546
    Abstract: A discharge lamp lighting apparatus includes a triangular signal oscillator, a first control part to compare the triangular signal with an error voltage between a reference voltage and a voltage corresponding to a first current passed through a secondary winding of a transformer and generate a first PWM control signal for turning on/off switching elements Qp1 and Qn1 with a phase difference of about 180 degrees and a pulse width corresponding to the first current, and a second control part to compare the triangular signal with an error voltage between a reference voltage and a voltage corresponding to a second current passed through a secondary winding S2 of a transformer T2 and turn on/off switching elements Qp2 and Qn2 in synchronization with the first PWM control signal with a phase difference of about 180 degrees and a pulse width corresponding to the second current.
    Type: Grant
    Filed: February 14, 2008
    Date of Patent: October 20, 2009
    Assignee: Sanken Electric Co., Ltd.
    Inventor: Kengo Kimura
  • Publication number: 20090256490
    Abstract: A voltage sensing circuit includes a voltage divider and a voltage rectifier. The voltage divider divides a first output voltage on a first output voltage line to a first divided output voltage. The voltage divider comprises a first metal foil and a first capacitor. The first metal foil and the first output voltage line can form a first capacitive component. The first capacitive component is coupled in series with the first capacitor. The first capacitive component and the first capacitor can generate the first divided output voltage. The voltage rectifier is coupled to the voltage divider and can rectify the first divided output voltage to a sensing voltage indicative of the first output voltage.
    Type: Application
    Filed: June 22, 2009
    Publication date: October 15, 2009
    Inventors: Youling Li, Yingpeng Hu, Xiaojun Wang
  • Publication number: 20090251062
    Abstract: A soft start circuit generates a soft start voltage which changes over time when light emission of an EEFL is started. A pulse modulator receives a feedback voltage that corresponds to the output voltage of an inverter and the soft start voltage, and adjusts the duty ratio of a pulse signal PWM such that these two voltages match one another using a feedback operation. A striking control circuit monitors an error signal which is asserted when an abnormal state occurs. In a case in which the error signal has been asserted at a detection timing after the soft start voltage has reached a target voltage, the striking control circuit resets and restarts the soft start circuit. A driver controls the switching of the voltage at the primary coil of a transformer according to the pulse signal received from the pulse modulator.
    Type: Application
    Filed: April 8, 2009
    Publication date: October 8, 2009
    Applicant: ROHM CO., LTD.
    Inventors: Junichi HAGINO, Kenichi FUKUMOTO
  • Publication number: 20090251061
    Abstract: The invention relates to an apparatus for operating at least one discharge lamp by means of one or more voltage converters, wherein the apparatus comprises a voltage converter which is in the form of an inverse Watkins-Johnson converter.
    Type: Application
    Filed: October 26, 2006
    Publication date: October 8, 2009
    Inventor: Bernhard Siessegger
  • Publication number: 20090243505
    Abstract: (1) An oscillator generates a triangular wave signal whose inclination for charging a capacitor and inclination for discharging the same are the same and which is used to turn on/off FETs Qp1 and Qn1, (2) a signal generation part generates first drive signal in a period shorter than a half period of the triangular wave signal to drive the Qp1, and generates a second drive signal having a pulse width substantially equal to that of the first drive signal and a phase difference of about 180 degrees with respect to the first drive signal, to drive the Qn1 and provide a current to the discharge tube in a direction opposite to the current driven by the first drive signal, and (3) a pulse current generation circuit converts a synchronization pulse voltage signal into a pulse current that alternates between positive and negative current values of the same absolute value at a duty of about 50% and superimposes the pulse current on the triangular wave signal to drive the first drive signal and the second drive signal.
    Type: Application
    Filed: September 10, 2007
    Publication date: October 1, 2009
    Applicant: SANKEN ELECTRIC CO., LTD.
    Inventor: Kengo Kimura
  • Patent number: 7589478
    Abstract: An inverter circuit for discharge lamps for multi-lamp lighting in which the value of a negative resistance characteristic of a fluorescent lamp is controlled, and an excessively set reactance is eliminated by causing a shunt transformer to have a reactance exceeding the negative resistance characteristic. Two coils connected to a secondary winding of a step-up transformer of the inverter circuit are arranged and magnetically coupled to each other to form a shunt transformer for shunting current such that magnetic fluxes generated thereby cancel each other out. Discharge lamps are connected to the coils, respectively, with currents flowing therethrough being balanced. Each discharge lamp is lighted because a reactance of an inductance related to the balancing operation which is in an operating frequency of the inverter circuit, exceeds a negative resistance of the discharge lamps.
    Type: Grant
    Filed: September 17, 2007
    Date of Patent: September 15, 2009
    Inventors: Masakazu Ushijima, Koji Kawamoto, Youichi Yamamoto, Kijima Minoru
  • Patent number: 7586269
    Abstract: A driving device for driving a lamp (L2) includes a power stage circuit (21), a transformer circuit (22), a resonance circuit (23) and a PWM controller (25). The power stage circuit converts a received direct current (DC) signal to an alternating current (AC) signal. The transformer circuit is connected to the power stage circuit, for stepping up the AC signal. The transformer circuit includes a transformer and a capacitor. The transformer has a primary winding and a secondary winding. The capacitor is connected between a high voltage terminal and a low voltage terminal of the secondary winding of the transformer. The PWM controller is connected to the power stage circuit, for controlling output of the power stage circuit.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: September 8, 2009
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Chih-Chan Ger, Ko-Wen Wang
  • Publication number: 20090219464
    Abstract: The invention relates to a control system for at least two light tubes connected to a common transformer circuit. The control system comprises a control circuit which is provided with at least two detection inlets (a2, a3) used for detecting lamp currents (I1, I2) passing through the first and second light tubes, respectively. The detected lamp currents (I1, I2) can be regulated to a day mode with a high current intensity, and in a night mode with a low current intensity by the control circuit. The lamp currents (I1, I2) can be detected individually in day mode and in a common manner in night mode. The control system reduces instability of the tubes, in particular flicker.
    Type: Application
    Filed: August 27, 2003
    Publication date: September 3, 2009
    Inventors: Christian Schanz, Matthias Rupprecht
  • 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
  • Patent number: 7579787
    Abstract: The present disclosure introduces a simple method and apparatus for converting DC power to AC power for driving discharge lamps such as a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL), or a flat fluorescent lamp (FFL). Among other advantages, the invention allows the proper protection under short circuit conditions for applications where the normal lamp current is greater than safe current limit.
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: August 25, 2009
    Assignee: Monolithic Power Systems, Inc.
    Inventors: Wei Chen, James C. Moyer, Paul Ueunten
  • Patent number: 7579784
    Abstract: A control circuit for controlling a switching element in a switching power supply by generating a switching signal is disclosed. The control circuit may include a soft start circuit that generates a switching signal so that an output voltage of the switching power supply gradually increases for a period until the output voltage reaches a predetermined reference voltage. The soft start circuit may increase the output voltage at a first limiting speed when the output voltage is lower than a predetermined threshold voltage, and may increase the output voltage at a second limiting speed which is set higher than the first limiting speed when the output voltage is higher than the threshold voltage.
    Type: Grant
    Filed: December 2, 2005
    Date of Patent: August 25, 2009
    Assignee: Rohm Co., Ltd.
    Inventors: Kyoichiro Araki, Yoichi Tamegai, Isao Yamamoto
  • Publication number: 20090206763
    Abstract: The described DC to AC inverter efficiently controls the amount of electrical power used to drive a cold cathode fluorescent lamp (CCFL). The output is a fairly pure sine wave which is proportional to an input control voltage. The output waveform purity is ensured by driving a symmetrical rectangular waveform into a second-order, low pass filter at the resonant frequency of the filter for all conditions of line voltage and delivered power. Operating stress on the step-up transformer is minimized by placing the load (lamp) directly across the secondary side of the transformer. When configured to regulate delivered power, the secondary side may be fully floated which practically eliminates a thermometer effect on the operation of the lamp. All of the active elements, including the power switches, may be integrated into a monolithic silicon circuit.
    Type: Application
    Filed: April 22, 2009
    Publication date: August 20, 2009
    Inventors: John Robert Shannon, James Copland Moyer, Michael Ren Hsing
  • Publication number: 20090195172
    Abstract: The present invention includes a PWM unit, a switch unit, a resonance unit, a transformer, a feedback unit and a frequency control unit, wherein the switch unit obtains a DC power from a power source, the PWM unit produces a working cycle signal to drive the switch unit to convert the DC power into a pulse power and the resonance unit converts the pulse power into a driving power for providing to the transformer to convert thereof into an output power, characterized in that when the resonance unit is under a starting frequency and a working frequency higher than the starting voltage, a starting voltage gain and a working voltage gain respectively corresponding thereto are produced, wherein the starting voltage gain is larger than the working voltage gain, so that the larger starting voltage gain can produce the output power with higher voltage to smoothly initiate the lamp tube set.
    Type: Application
    Filed: February 1, 2008
    Publication date: August 6, 2009
    Inventors: Shih An LIANG, Kuo-Hei Lee, Ken-Chuan Hsu
  • Publication number: 20090195177
    Abstract: To provide a low-cost self-excited inverter driving circuit exhibiting an excellent operational efficiency. A main inverter section is so constructed that a part of output signals is fed back by a resonance loop circuit to cause a self-excited oscillation to occur in the vicinity of a resonance frequency decided by leakage inductors and capacitors on the secondary side of a high voltage transformer, thereby performing an inverter operation. It is further arranged that a halt interval setting signal, which is generated by a triangular wave forming circuit and a control section, is applied to the main inverter section, thereby halting the inverter operation in accordance with the halt interval setting signal.
    Type: Application
    Filed: June 28, 2006
    Publication date: August 6, 2009
    Applicant: SUMIDA CORPORATION
    Inventor: Hiroyuki Miyazaki
  • Publication number: 20090189535
    Abstract: A transformer wiring method and apparatus for fluorescent lighting are described. The fluorescent lighting apparatus includes a transformer and a ballast. An installer is easily able to balance the system load because each fluorescent lighting apparatus includes its own transformer and may be connected directly to a facility's three phase power distribution while still operating at rated voltages. Moreover, the ballast is protected from surges and stray voltages thereby reducing the frequency of ballast failures.
    Type: Application
    Filed: January 29, 2008
    Publication date: July 30, 2009
    Inventors: Neal R. Verfuerth, Anthony J. Bartol, Ronald E. Ernst, Kenneth J. Wetenkamp
  • Publication number: 20090189536
    Abstract: The invention is a driving apparatus and circuit for efficiently converting a direct current (DC) signal into an alternating current (AC) signal to drive a fluorescent lamp. A semi class E configuration which utilizes only one transistor is employed in the invention. The invention comprises a power transistor, a transformer wherein a primary winding is used as a load for the power transistor and a secondary winding is used to transfer energy to the load for the driving apparatus, i.e. the CCFL tube, and control means which extracts the frequency and current of the power transistor and corrects the deviation between the frequency of the power transistor and that of the control means.
    Type: Application
    Filed: January 30, 2009
    Publication date: July 30, 2009
    Applicant: HIMAX TECHNOLOGIES, INC.
    Inventors: Shwang-Shi Bai, Yu-Pei Huang, Shen-Yao Liang, Shu-Ming Chang
  • Patent number: 7567039
    Abstract: A multiple discharge lamp lighting apparatus is provided which achieves stable and uniform lamp currents in a plurality of discharge lamps without a ballast element at the secondary side of an inverter transformer. The multiple discharge lamp lighting apparatus includes an inverter, and a plurality of inverter transformers each of which has a discharge lamp connected at a secondary winding thereof. A balance inductance element is provided between the primary side wirings of any adjacent pair of the plurality of inverter transformers. Each of the inverter transformers includes a tight coupling section and a loose coupling section, which function as a balance coil and an impedance element, respectively, whereby the lamp currents of the discharge lamps are stabilized and equalized without using a high withstand voltage element.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: July 28, 2009
    Assignee: Minebea Co., Ltd.
    Inventors: Hiroshi Shinmen, Robert Weger
  • Patent number: 7567040
    Abstract: An efficient power driver for color light emitting diodes (LED) is disclosed for driving multiple LEDs for producing different desired colors. Such LED combinations comprising LEDs with different primary colors are suitable for implementing pixels in displaying a digitized image. This disclosed invention provides switching power conversion embodiments such that a single apparatus drives different color LEDs. Furthermore, the disclosed invention provides configurations with and without input to output isolation while enabling control of the current through each LED, for instance by an inductor or operating condition.
    Type: Grant
    Filed: October 24, 2006
    Date of Patent: July 28, 2009
    Assignee: The University of Hong Kong
    Inventors: Man Hay Pong, Franki Ngai Kit Poon, Joe Chui Pong Liu
  • Publication number: 20090184654
    Abstract: Primary and secondary regions are electrically insulated from each other. The first and second pulse transformers are provided to the respective transistors in the switching circuit. Secondary windings of the first and second pulse transformers are connected to control terminals of the transistors. The control circuit supplies switching voltages to primary windings of the pulse transformers based on a feedback signal fed back through a feedback line. A primary winding of a transformer, the switching circuit, and the secondary windings are disposed on the primary region. A secondary winding of the transformer, the primary windings, the feedback line, and the control circuit are disposed on the secondary region.
    Type: Application
    Filed: March 19, 2009
    Publication date: July 23, 2009
    Applicant: ROHM CO., LTD.
    Inventor: Kenichi FUKUMOTO
  • Patent number: 7564191
    Abstract: An inverter has an inductor, a capacitor, a switching device, a driving circuit and a transformer. A first terminal of the capacitor is connected to the inductor, and the switching device is connected between the first terminal of the capacitor and a ground terminal. The driving circuit is connected to the switching device, wherein the driving circuit is arranged to control the switching device to turn on or turn off; and a primary side of the transformer is connected between a second terminal of the capacitor and the ground terminal.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: July 21, 2009
    Assignee: Himax Technologies Limited
    Inventors: Shu-Ming Chang, Yu-Pei Huang, Shen-Yao Liang, Shwang-Shi Bai
  • Patent number: 7564193
    Abstract: A phase-modulated, double-ended, full-bridge topology-based DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load.
    Type: Grant
    Filed: July 6, 2005
    Date of Patent: July 21, 2009
    Assignee: Intersil Americas Inc.
    Inventors: Robert L. Lyle, Jr., Steven P. Laur, Zaki Moussaoui
  • Patent number: 7559674
    Abstract: A LED lighting arrangement includes a support body having mounted thereon one or more LED lighting sources and a driver or feeding the LED lighting sources. The support body includes a high-voltage section carrying the driver and a low-voltage section carrying, mounted on a heat sink, the light sources. An insulation barrier is provided between the high voltage section and the low-voltage section of the board with a twisted pair forming a wiring that traverses the insulation barrier to connect the driver and the LED lighting sources.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: July 14, 2009
    Assignee: Osram Gesellschaft mit beschraenkter Haftung
    Inventors: Xi Yuan He, Rui Ma, Giovanni Scilla
  • Publication number: 20090174339
    Abstract: An electronic circuit topology (1) for driving a predominantly capacitive load (2) with a primary circuit with several components, a secondary circuit with a predominantly capacitive load (2), and a transformer device (4) with a primary side (TX 1a) and a secondary side (TX 1b), connecting the primary circuit with the secondary circuit, the primary circuit components comprise: a source device (3), a drain device (5), and a switching device (6), the transformer device (4) is for transforming an input voltage-current-signal to a suitable output voltage-current signal for supplying the predominantly capacitive load (2), wherein the source device (3) is in serial connection with the transformer device (4), the drain device (5), and the switching device (6), whereby the transformer device (4) comprises means for functioning as a resonant tank circuit, as a transformer device (4) in forward mode, and as a transformer device (4) in flyback mode, so that an single-ended forward-flyback circuit is achieved.
    Type: Application
    Filed: December 22, 2004
    Publication date: July 9, 2009
    Inventors: Marc Maria Alex Bleukx, Wolfgang Schiene, Heinrich Von Busch, Stefan Schwan
  • Patent number: 7557516
    Abstract: The present invention provides a low-cost inverter for ballast. A current transformer is connected in series with a lamp to operate the lamp. A first transistor and a second transistor are coupled to switch the resonant circuit. The current transformer is utilized to generating control signals in response to the switching current of the resonant circuit. The transistor is turned on once the control signal is higher than a first threshold. After that, the transistor is turned off once the control signal is lower than a second threshold. Therefore, a soft switching operation for the first transistor and the second transistor can be achieved.
    Type: Grant
    Filed: March 21, 2007
    Date of Patent: July 7, 2009
    Assignee: System General Corp.
    Inventors: Ta-yung Yang, Jea-Sen Lin
  • Patent number: 7557514
    Abstract: While series resonant circuits 51 to 53 are connected to an output stage of a switching circuit 101 so as to be parallel mutually, primary sides of booster transformer sections 1 to 3 are connected to resonance capacitors 14 to 16 respectively, and further, CCFLs 21 to 23 are connected to secondary sides of the booster transformer sections 1 to 3 respectively.
    Type: Grant
    Filed: June 28, 2007
    Date of Patent: July 7, 2009
    Assignee: Sumida Corporation
    Inventors: Hiroyuki Miyazaki, Takeshi Hatakeyama
  • Publication number: 20090160352
    Abstract: A discharge tube lighting apparatus includes a converter that converts a voltage received from an alternating-current or direct-current power supply into a predetermined direct-current voltage and an inverter that converts an output voltage of the converter into an alternating-current voltage having a predetermined frequency. The inverter performs burst control based on an externally input dimming signal. The converter operates regardless of the active or inactive period of the burst control of the inverter and performs negative feedback control in response to a detection signal of a tube current in the active period of the inverter.
    Type: Application
    Filed: March 13, 2009
    Publication date: June 25, 2009
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Akio NISHIDA, Shigeru ARAI
  • Patent number: 7550928
    Abstract: The present invention provides a driving circuit for driving a light source. The driving circuit includes a serial-arranged transformers system having multiple primary windings and secondary windings; a first switch conducting current though a first path and a second switch conducting current though a second path. The first path is a first set of primary windings connected in series and the second path is a second set of primary windings connected in series and the first set of primary transformer windings and the second set of primary transformer windings form the dual primary windings of the transformers respectively. Based on the conduction of each switch, a DC voltage source supplies power to the primary windings of the transformers, which in turn powers on the light source connected to the secondary windings of the transformers.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: June 23, 2009
    Assignee: O2Micro International Limited
    Inventor: Da Liu
  • Publication number: 20090153069
    Abstract: A small balancer coil for cold-cathode florescent lamps having sufficient shunt/balance effects, comprises a discharge lamp, a conductor located close to the discharge lamp, and two coils whose magnetic fluxes face each other. The magnetic fluxes generated in the coils face and cancel each other. Lamp currents of the discharge lamps are balanced by making the sum of the reactances of the mutual inductance of the balancer coil larger than the negative resistance of the discharge lamp. Section winding is applied to each coil of the balancer coil so as to maintain shunt and balance effects even in a small/flat balancer coil by making self-resonance frequency of each of the coils higher.
    Type: Application
    Filed: December 1, 2008
    Publication date: June 18, 2009
    Inventor: Masakazu Ushijima
  • Patent number: 7548028
    Abstract: A high conversion efficiency inverter circuit by providing the current-mode resonant type efficient in using a power source.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: June 16, 2009
    Inventor: Masakazu Ushijima
  • Patent number: 7545106
    Abstract: A discharge lamp driving device for driving a lamp module (23) including a plurality of lamps includes a switch circuit (21), a transformer and filter circuit (22), and a microcontroller (20). The switch circuit converts a received signal to an alternating current signal. The transformer and filter circuit is connected between the switch circuit and the lamp module, for amplifying and shaping the alternating current signal. The microcontroller connected to the switch circuit for outputting a control signal to control the switch circuit to output the alternating current signal to the lamp module. In the invention, correlative parameters and specifications of the circuit are predetermined via the microcontroller. Therefore, the structure of the whole circuit is simple.
    Type: Grant
    Filed: July 13, 2006
    Date of Patent: June 9, 2009
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Chih-Chan Ger, Chia-Ming Chang
  • Publication number: 20090140662
    Abstract: The present invention relates to a circuit arrangement having a transformation apparatus, which has a primary side (P) and a secondary side (S), wherein the primary side and the secondary side (S) are DC-isolated from one another, wherein the primary side (P) has a terminal for a supply voltage (UE) and is connected to a first reference potential, wherein the secondary side (S) comprises a first and a second output line, which, in the normal case, are not coupled to a reference potential and which form an output terminal, at which a voltage for a load (LA) can be provided, wherein it furthermore comprises: an apparatus for tapping off a measured voltage potential (CP) on the secondary side (S); and an apparatus (10) for determining whether the measured voltage potential is in a permissible range. The invention moreover relates to an operating method for a lamp using a circuit arrangement.
    Type: Application
    Filed: February 21, 2007
    Publication date: June 4, 2009
    Applicant: OSRAM GESELLSCHAFT MIT BESCHRANTER HAFTUNG
    Inventors: Harald Dellian, Arnulf Rupp, Oskar Schallmoser
  • Publication number: 20090115342
    Abstract: A lighting system for illuminating a chamber in a building includes a lighting fixture suitable for being mounted onto a surface of the chamber, so that light emitted by at least one CCFL device mechanically supported by the fixture illuminates the chamber. The one CCFL device includes at least one transformer. A driver adapted to be connected to a surface of the chamber is capable of converting input power from a power source to an AC power having a voltage in the range of about 5-400 volts and a current at a frequency in the range of about 1 kc-100 kc. The at least one transformer is suitable for converting the AC power to an output power suitable for operating the at least one CCFL, causing the at least one CCFL to emit light. Physically separating the driver from the at least one CCFL device reduces the adverse effects of heat generated by the at least one CCFL device on the driver and increasing the useful life of the CCFL lighting system.
    Type: Application
    Filed: November 2, 2007
    Publication date: May 7, 2009
    Inventors: Victor Lam, Shichao Ge