With Power Factor Control Device Patents (Class 315/247)
  • Patent number: 9392660
    Abstract: An illumination device and method is provided herein for calibrating individual LEDs and photodetector(s) included within the illumination device, so as to obtain a desired luminous flux and a desired chromaticity of the device over time as the LEDs age. Specifically, a calibration method is provided herein for characterizing each emission LED and each photodetector separately. The wavelength and intensity of the illumination produced by each emission LED is accurately characterized over a plurality of different drive currents and ambient temperatures, and at least a subset of the wavelength and intensity measurement values are stored with a storage medium of the illumination device for each emission LED. The responsivity of the photodetector is accurately characterized over emitter wavelength and photodetector junction temperature, and results of said characterization are stored with the storage medium.
    Type: Grant
    Filed: August 28, 2014
    Date of Patent: July 12, 2016
    Assignee: Ketra, Inc.
    Inventors: Alcides Jose Dias, Jason E. Lewis
  • Patent number: 9385598
    Abstract: A low voltage lamp includes a boost converter stage and a load. The load may include low voltage light producing elements including low voltage light emitting diodes. The boost converter stage receives an electronic transformer output and includes an inductor coupled to a switch and a switch controller that receives one or more controller inputs. Inductor current may be returned to the transformer when the switch is closed and provided to a rectifier coupled to the load when the switch is open. Controller inputs may include a transformer input that receives the transformer output, a sense input indicating switch current, and a load input indicating load voltage. Controller logic may synchronize assertions of a control signal for the switch with edge transitions of the transformer output to maintain peak inductor current within a specified range and to selectively transfer stored energy in the inductor to the load or back to the transformer.
    Type: Grant
    Filed: June 12, 2014
    Date of Patent: July 5, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Kan Wang, Michael A. Kost, Eric J. King, John L. Melanson, James P. McFarland
  • Patent number: 9380655
    Abstract: A single-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The AC-DC power converter includes a high power factor correction (PFC) circuit configured in a flyback topology and operating in transition mode. The flyback PFC circuit outputs a direct current (DC) voltage and a DC current. The PFC circuit further includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided to the load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents. The switch circuit includes a switch and three, fast Schottky diodes.
    Type: Grant
    Filed: October 1, 2013
    Date of Patent: June 28, 2016
    Assignee: GENERAL ELECTRIC COMPANY
    Inventor: Yehuda Daniel Levy
  • Patent number: 9351370
    Abstract: An LED (Light Emitting Diode) controller comprises a first LED driver to generate a first PWM (Pulse Width Modulation) drive signal to turn on or turn off, respectively, a first current through a first LED string. Additionally, the LED controller comprises a compensation circuit to generate the first PWM drive signal responsive to a first duty set signals. The first duty set signal is indicative of a first duty cycle set for the first PWM drive signal. The compensation circuit receives a first feedback signal indicative of the first current, generates a first error signal indicative of a difference between a first predetermined target value and the first feedback signal, and generates the first PWM drive signal to have the first duty cycle corresponding to the first duty set signal and further adjusted by the first error signal.
    Type: Grant
    Filed: September 12, 2014
    Date of Patent: May 24, 2016
    Assignee: Dialog Semiconductor Inc.
    Inventors: Andrey B. Malinin, Enzhu Liang, Yuwen Wang
  • Patent number: 9350248
    Abstract: The power supply device of the present invention includes a main converter and at least one sub converter connected in parallel between a pair of output ends of a DC power supply circuit for receiving power through a parallel circuit of a thyristor and a thermistor having a positive temperature coefficient. Each of the main converter and the at least one sub converter includes: a series circuit composed of a diode and a switching element and connected between the pair of output ends; a series circuit composed of a capacitor and an inductor and connected in parallel with the diode; and a drive circuit configured to drive the switching element. The main converter controls the thyristor in accordance with a voltage across a secondary winding magnetically coupled with the inductor. When a short circuit of the switching element of the at least one sub converter occurs, the drive circuit of the main converter terminates driving of the switching element of the main converter.
    Type: Grant
    Filed: July 26, 2013
    Date of Patent: May 24, 2016
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventor: Kazuhiro Kumada
  • Patent number: 9326333
    Abstract: According to one embodiment, a flyback power converter comprises a primary circuit including a flyback driver, and an isolated output circuit responsive to the primary circuit. The isolated output circuit is used to power a load. The flyback driver is configured to identify a load current in the isolated output circuit from an input power to the primary circuit, and to regulate the load current according to the input power. In one embodiment, the flyback driver is configured to sense an input voltage to the flyback power converter, to identify an average current value corresponding to a current through a converter switch in the primary circuit, and to multiply the average current value and the input voltage to determine the input power to the primary circuit.
    Type: Grant
    Filed: October 14, 2011
    Date of Patent: April 26, 2016
    Assignee: Infineon Technologies Americas Corp.
    Inventors: Peter B. Green, Dana Wilhelm
  • Patent number: 9326344
    Abstract: Dimmable LED light source comprising: —a rectifier having rectifier input terminals for connection to respective output terminals of a phase cut dimmer of the trailing edge type, input terminals of the phase cut dimmer being connected to the mains supply, and having a first rectifier output terminal and a second rectifier output terminal, —a bleeder circuit connecting the rectifier output terminals, —a series arrangement comprising a first unidirectional element and first capacitive means connecting the rectifier output terminals, —a converter circuit, having input terminals coupled to respective sides of the first capacitive means and output terminals coupled to a LED load, for generating a current through the LED load, in dependence on a dim signal, out of a voltage present across the capacitive means, —a dim circuit for generating a dim signal as a function of the adjusted phase angle of the phase cut dimmer and for supplying the dim signal to a dim input of the converter circuit, —a series arrangement com
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: April 26, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Dmytro Viktorovych Malyna, Patrick Alouisius Martina De Bruycker, Harald Josef Gunther Rademacher
  • Patent number: 9324277
    Abstract: The present invention provides a backlight drive circuit, and a liquid crystal display and a drive method for the same, wherein the backlight drive circuit includes: an error amplification unit configured to receive a feedback voltage from the backlight, and used for comparing the feedback voltage with a basis voltage, adjusting the amplification coefficient and the amplification speed for a comparison result based on the magnitude of the comparison result, and outputting an amplification result as a control signal; and a drive control unit configured to receive the control signal from the error amplification unit, and used for outputting, according to the control signal, a pulse width modulation dimming signal with a corresponding duty cycle to modulate a voltage signal output to the backlight from a power supply. The backlight drive circuit may be applied to driving operation for various display devises and capable of automatically adjusting response rate under different loading modes.
    Type: Grant
    Filed: January 22, 2014
    Date of Patent: April 26, 2016
    Assignee: SHENZHEN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD.
    Inventor: Xiang Yang
  • Patent number: 9306592
    Abstract: A feedback loop, which feedbacks information of an output voltage or a load current, is provided. The feedback loop has a first mode, which digitalizes and feedbacks the information of the current voltage or the load current, and a second mode, which feedbacks the information as an analog value.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: April 5, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Chen Kong Teh
  • Patent number: 9300113
    Abstract: A laser device includes a plurality of lasers that includes a first laser and a second laser. The laser device further includes a drive circuit configured to apply a pulsed current to the first laser at a first phase. The drive circuit is further configured to apply the pulsed current to the second laser at a second phase. The first phase and the second phase are different. A total voltage provided to the plurality of lasers during a period between the first and second phases is substantially smaller than a sum of individual voltages provided to the plurality of lasers, respectively, during a pulse period of the pulsed current.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: March 29, 2016
    Assignee: Versatile Power, Inc.
    Inventors: David Hoffman, Alexandr Ikriannikov
  • Patent number: 9295143
    Abstract: A lighting system includes circuitry to provide wireless LED driver or fluorescent ballast control without requiring changes to existing wiring setups. A power stage includes a power converter coupled across a first set of power terminals. The first power terminals are coupled to a second set of terminals via the wiring. A load stage is coupled to the second power terminals, wherein power provided across the first set of terminals is received by the load stage and deliverable to lighting devices. The load stage further includes a dimming control signal receiver coupled across the second set of power terminals and configured to receive an encoded dimming control signal. The encoded signal is transmitted across the wiring setup, wherein the power stage further includes a dimming control signal decoder coupled across the first set of power terminals and effective to deliver a decoded dimming control signal to the controller.
    Type: Grant
    Filed: August 28, 2014
    Date of Patent: March 22, 2016
    Assignee: Universal Lighting Technologies, Inc.
    Inventors: Wei Xiong, Travis L. Berry, Keith Davis
  • Patent number: 9295116
    Abstract: A switched-capacitor voltage converter which is particularly well-suited for receiving a line voltage from which to drive current through a series of light emitting diodes (LEDs). Input voltage is rectified in a multi-level rectifier network having switched capacitors in an ascending-bank configuration for passing voltages in uniform steps between zero volts up to full received voltage VDC. A regulator section, operating on VDC, comprises switched-capacitor stages of H-bridge switching and flying capacitors. A current controlled oscillator drives the states of the switched-capacitor stages and changes its frequency to maintain a constant current to the load. Embodiments are described for isolating the load from the mains, utilizing an LC tank circuit or a multi-primary-winding transformer.
    Type: Grant
    Filed: June 2, 2014
    Date of Patent: March 22, 2016
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Seth R. Sanders, Mitchell Kline
  • Patent number: 9288853
    Abstract: The present invention discloses an LED driving circuit and controller, capable of maintaining an average value of a current flowing through an LED module at a predetermined current value. The LED driving circuit and controller compensates influences of any factors deviating the average value of the current flowing through the LED module by modulating a period of constant on time or constant off time, or by modulating the determining value(s) of current peak value and/or current valley value according to a difference between an actual average value and the preset current value.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: March 15, 2016
    Assignee: GREEN SOLUTION TECHNOLOGY CO., LTD.
    Inventor: Chung-Che Yu
  • Patent number: 9277613
    Abstract: Method and means for driving one or more LEDs. The method includes turning a power switch on to provide current through an inductor and the power switch, measuring voltseconds of the LEDs at a cycle time, comparing the measured voltseconds to a reference signal at an end of the cycle time, generating a signed discrete logical signal based on a difference between the measured voltseconds and the reference signal, and generating a control signal using the signed discrete logical signal to regulate a peak current through the power switch by keeping the cycle time voltseconds substantially constant. The reference signal may be proportional to a set average LED voltage.
    Type: Grant
    Filed: November 10, 2014
    Date of Patent: March 1, 2016
    Assignee: Chemtron Research LLC
    Inventors: Anatoly Shteynberg, Harry Rodriguez
  • Patent number: 9270169
    Abstract: In various embodiments, a control system for an electronic circuit iteratively applies voltage to and senses current from a load to regulate operation of the load.
    Type: Grant
    Filed: November 11, 2014
    Date of Patent: February 23, 2016
    Assignee: Cooledge Lighting, Inc.
    Inventors: Michael A. Tischler, William P. Coetzee, Paul Jungwirth
  • Patent number: 9263953
    Abstract: Embodiments of the invention provide a power supply apparatus, including an AC/DC rectifying unit converting an AC voltage into a DC voltage, a power factor correction unit correcting a power factor of the DC voltage, and a DC/DC conversion unit converting the DC voltage having the corrected power factor into a DC voltage having a different magnitude therefrom. According to various embodiments, the power supply apparatus further includes an auxiliary winding connected to a primary side winding of a transformer of the DC/DC conversion unit and generating the DC voltage having a predetermined magnitude, and an internal power generation unit connected to an output terminal of the power factor correction unit and the auxiliary winding and using a voltage of the output terminal of the power factor correction unit and a voltage generated by the auxiliary winding to generate temporary Vcc power and supply the generated temporary Vcc power as internal power of the power factor correction unit.
    Type: Grant
    Filed: October 1, 2014
    Date of Patent: February 16, 2016
    Assignee: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventors: Jeong Nam Lee, Yeon Ho Jeong
  • Patent number: 9258858
    Abstract: The present invention relates to an active capacitor circuit (40) for use in a driver device for driving a load (22), in particular an LED unit comprising one or more LEDs (23). Further, the present invention relates to a driver device comprising such an active capacitor circuit.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: February 9, 2016
    Assignee: Koninklijke Philips N.V.
    Inventors: Reinhold Elferich, Toni Lopez
  • Patent number: 9252679
    Abstract: A reverse recovery current prevention device includes a full wave rectifier having a plurality of diodes, first and second diodes, a switch part and a switch control unit. The full wave rectifier rectifies a power source voltage from an alternating current power source inputted into first and second input terminals. The first and second diodes have anode terminals connected to the first and second input terminals, respectively. The switch part opens or shorts an electrical circuit between a negative-side output terminal of the full wave rectifier and each cathode terminal of the first and second diodes. The switch control unit prohibits the switch part from shorting the electrical circuit between the negative-side output terminal and each of the cathode terminals when a voltage between the negative-side output terminal and each of the cathode terminals is at or above a threshold.
    Type: Grant
    Filed: December 2, 2010
    Date of Patent: February 2, 2016
    Assignee: Daikin Industries, Ltd.
    Inventors: Motonobu Ikeda, Satoshi Yagi, Sumio Kagimura
  • Patent number: 9253834
    Abstract: A LED driving circuit having a sensing unit is disclosed. The LED driving circuit includes an input unit configured to receive a dimming signal to drive an LED array, a DC-DC converter including a power transistor configured to perform a switching operation, the DC-DC converter being configured to provide an output voltage to the LED array by the switching operation, a PWM signal generating unit configured to provide a PWM signal to adjust power of the LED array to the power transistor, a LED driving unit configured to drive the LED array using the dimming signal, and a sensing unit configured to sense degradation of the power transistor.
    Type: Grant
    Filed: June 4, 2012
    Date of Patent: February 2, 2016
    Assignee: Magnachip Semiconductor, Ltd.
    Inventors: Hyoung-kyu Kim, Tae-kyoung Kang, Gyu-ho Lim, Jin-wook Kim
  • Patent number: 9250644
    Abstract: A power conversion system in an electronic device is utilized for converting an input voltage of a power source terminal to a required voltage of a load circuit to provide power to the load circuit. The power conversion system includes a first voltage conversion circuit for converting the input voltage to the required voltage of the load circuit according to a first control signal; and a power control module for generating the first control signal according to a starting signal or a load voltage of the load circuit; wherein the load circuit receives the voltage outputted from the first voltage conversion circuit to perform operations.
    Type: Grant
    Filed: May 19, 2014
    Date of Patent: February 2, 2016
    Assignee: Sitronix Technology Corp.
    Inventors: Chung-Hsin Su, Tsun-Sen Lin
  • Patent number: 9253850
    Abstract: A light system (FIG. 2) is disclosed. The light system includes a plurality of series connected light emitting diodes (240-246). Each of a plurality of switching devices (230-236) has a control terminal and each has a current path coupled in parallel with a respective LED. A plurality of fault detector circuits (220-226) are each coupled in parallel with a respective light emitting diode. Each fault detector circuit has a first comparator (FIG. 7, 704) arranged to compare a voltage across the respective light emitting diode to a respective first reference voltage (708). When a fault is defected, a control signal is applied to the control terminal to turn on a respective switching device of the plurality of switching devices.
    Type: Grant
    Filed: April 26, 2013
    Date of Patent: February 2, 2016
    Assignees: Texas Instruments Incorporated, Texas Instruments Deutschland GmbH
    Inventors: Joseph V. DeNicholas, Perry Tsao, Christoph Goeltner, Daniel Ross Herrington, James Masson, James Patterson, Werner Berns
  • Patent number: 9235109
    Abstract: A switching power source for driving a light emitting element, a pulse-drive switching element connected in parallel to the light emitting element, a photodetector for detecting an intensity of an output light output from the light emitting element, a current detecting element for detecting a current flowing from the switching power source, and an operation processing unit that controls an operation of the switching power source by performing a feedback loop operation based on a detection result from the photodetector and a feedback loop operation based on a detection result from the current detecting element are provided to stabilize an emission waveform even when the light emitting element is subjected to a pulsed emission.
    Type: Grant
    Filed: October 18, 2010
    Date of Patent: January 12, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takahiko Yamamuro, Shigeki Harada
  • Patent number: 9232596
    Abstract: Driver circuits which reduce or remove flicker of solid state lighting SSL devices, notably at relatively low dimming levels are presented. The driver circuit comprises a power converter to transfer energy from an input of the driver circuit to the SSL device. The energy at the input is derived from an AC mains voltage at a mains frequency. A controller determines a dim level for the SSL device. and operates the power converter continuously in a first operation mode for supplying energy to the SSL device at a first energy level, if the dim level is above a pre-determined dim level threshold. The controller operates the power converter in the first operation mode at a time duration of PWM pulses, and operates the power converter in a second operation mode at a time duration in-between the PWM pulses, if the dim level is below the pre-determined dim level threshold.
    Type: Grant
    Filed: March 11, 2015
    Date of Patent: January 5, 2016
    Assignee: Dialog Semiconductor (UK) Limited
    Inventors: Nebojsa Jelaca, Stefan Zudrell-Koch
  • Patent number: 9232608
    Abstract: A light emitting device includes light emission units, a voltage generator, a lighting selector, and a drive control unit. Each light emission unit includes light emitting component groups each of which includes a light emitting component array and a drive switch. The light emitting component array includes light emitting components that are connected in series. The drive switch is connected in series to the light emitting component array to drive the light emitting component array. The lighting selector selects the light emitting component group that is to be lit on according to brightness intensity required for each light emission unit. The drive control unit controls each drive switch independently according to the selection by the lighting selector and controls to light on each light emitting component group independently and controls the voltage generator to generate a common drive voltage.
    Type: Grant
    Filed: July 5, 2011
    Date of Patent: January 5, 2016
    Assignee: SHARP KABUSHIKI KAISHA
    Inventor: Tsukasa Fujita
  • Patent number: 9226354
    Abstract: An LED lighting device includes a slave driving stage and a master driving stage. The slave driving stage includes a first luminescent device and a first current controller for providing a constant current setting in an ON phase. The master driving stage includes a second luminescent device and a current control unit having a second current controller and a current envelope controller. The second current controller provides a current envelope in the ON phase. The current envelope controller sets a level of the current envelope according to a rectified AC voltage. The driving current is regulated by the first current controller according to the constant current setting when the constant current setting is smaller than the level of the current envelope, or by the second current controller according to the current envelope when the level of the current envelope is smaller than the constant current setting.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: December 29, 2015
    Assignee: IML International
    Inventors: Horng-Bin Hsu, Yi-Mei Li, Yung-Hsin Chiang
  • Patent number: 9204513
    Abstract: An LED driver circuit includes light-element lines, a general purpose LED driving circuit that controls a current value, and current compensation lines respectively connected to the light-element lines. Each of the current compensation lines is provided with a fixed current source and a switch, and the switch switches an open/closed state of the current compensation line.
    Type: Grant
    Filed: October 2, 2013
    Date of Patent: December 1, 2015
    Assignee: SHARP KABUSHIKI KAISHA
    Inventor: Takeshi Takarada
  • Patent number: 9203410
    Abstract: Disclosed is a circuit for reducing EMI noise in a driver IC including at least one or more input ports, and at least one or more output ports, the circuit including a power unit connected to any one of the input ports to output a current to the driver IC, and at least one or more resistors arranged in series between the at least one or more output ports of the driver IC and an output terminal connecting an exterior device operated by the driver IC.
    Type: Grant
    Filed: November 28, 2011
    Date of Patent: December 1, 2015
    Assignee: LG INNOTEK CO., LTD.
    Inventor: Jinseob Lee
  • Patent number: 9190895
    Abstract: A circuit for controlling load switch is disclosed in the present invention. The circuit is applied to a load circuit which includes a load switch and a working element. The circuit includes a first comparator, a second comparator, and a third comparator. When an inductance current achieves the average current, the first comparator triggered to conduct a first switch. When the inductance current achieves a default ripple current, the second comparator is triggered to conduct a second switch. When either one of the first switch and the second switch is conducted, the load switch is turned off to make a variable voltage be increased. When the first switch is conducted, a capacitance voltage of a controlled capacitance is increased to increase a turned-off time. When the second switch is conducted, the capacitance voltage is decreased to decrease the turned-off time to control the load switch.
    Type: Grant
    Filed: August 11, 2015
    Date of Patent: November 17, 2015
    Assignee: Feeling Technology Corp.
    Inventor: Yi-Sheng Chen
  • Patent number: 9173257
    Abstract: A low voltage dimmer for LED lamps incorporates an AC-DC power supply along with a Pulse Width Modulator (PWM) to modify the power delivered to an LED load is configured to fit inside the form factor of a standard single gang electrical to control the intensity of the light emitted by the LED. The PWM portion of the dimmer circuit incorporates a microprocessor configured to produce a train of output pulses and controlled by a variable input voltage to modulate the output duty cycle of these pulses to drive one or more LED lamps to switch between “on” and “off” conditions. Variation of the duty cycle of the pulses regulates the total amount of time in each cycle that the lamp is illuminated, with the aggregate “on” time determining the apparent brightness of the lamp.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: October 27, 2015
    Inventor: Victor M. Cubias
  • Patent number: 9166483
    Abstract: A single-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The AC-DC power converter includes a high power factor correction (PFC) circuit configured in a flyback topology and operating in transition mode. The flyback PFC circuit has a PFC controller and is configured to draw an input AC current from an AC power supply. The input AC current has a first total harmonic distortion (THD). The flyback PFC circuit outputs a DC current to the load. The PFC controller is configured to sense a rectified input voltage. By multiplying the rectified input voltage sensed by the PFC controller, the input AC current drawn by the flyback PFC circuit has a second, much improved THD, which is achievable without the need of an expensive PFC controller. The rectified input voltage sensed by the PFC controller is multiplied using a Zener diode ladder.
    Type: Grant
    Filed: October 1, 2013
    Date of Patent: October 20, 2015
    Assignee: GENERAL ELECTRIC COMPANY
    Inventor: Yehuda Daniel Levy
  • Patent number: 9166470
    Abstract: A method and circuit for correcting a power factor in an alternating current/direct current power transformer. The circuit has an inductor fed by a rectified AC voltage, and a switch by which the inductor can be charged and discharged by closing and opening the switch, and further has a diode by which the discharge current of the inductor is fed to the output of the circuit. During the discharge phase, a voltage corresponding to the output voltage is measured, and the measured values are stored. It is further determined when the discharge current reaches or crosses the zero line at the end of a discharge phase. Switch-on and switch-off signals for actuating the switch are generated by analyzing the information determined. The switch should not be switched on again until a particular minimum switch-off time has been reached.
    Type: Grant
    Filed: July 7, 2010
    Date of Patent: October 20, 2015
    Assignee: TRIDONIC GmbH & CO. KG
    Inventor: Jamie Kelly
  • Patent number: 9167654
    Abstract: A solid light source lighting device includes: a step-down chopper circuit including a switching element and outputting a DC power by turning on and off the switching element; a capacitor connected in parallel to a solid light source connected across output terminals of the step-down chopper circuit; and a control circuit determining a control value for a switching operation of the switching element based on a dimming signal for indicating a dimming ratio of the solid light source, and performing switching control of the switching element based on the control value. When performing switching control of the switching element so that the dimming ratio becomes high based on the dimming signal indicating a first dimming ratio, the control circuit performs the switching control of the switching element based on the control value that becomes a second dimming ratio higher than the first dimming ratio for a prescribed time period.
    Type: Grant
    Filed: June 11, 2013
    Date of Patent: October 20, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Koji Watanabe, Yoshifumi Kuroki
  • Patent number: 9155163
    Abstract: In at least one embodiment, an electronic system includes a controller, and the controller provides compatibility between an electronic light source and a trailing edge dimmer. In at least one embodiment, the controller is capable of predicting an estimated occurrence of a trailing edge of a phase cut AC voltage and accelerating a transition of the phase cut AC voltage from the trailing edge to a predetermined voltage threshold. In at least one embodiment, the controller predicts an estimated occurrence of the trailing edge of the phase cut AC voltage on the basis of actual observations from one or more previous cycles of the phase cut AC voltage.
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: October 6, 2015
    Assignee: Cirrus Logic, Inc.
    Inventors: John L. Melanson, Eric J. King
  • Patent number: 9155174
    Abstract: A power control/lighting system includes a controller to provide compatibility between a lamp ballast configured to receive a dedicated dimmer signal and a phase control dimmer. In at least one embodiment, the controller converts a phase control dimming signal into dimming information useable by a lamp ballast of a gas discharge lamp based lighting system. Additionally, in at least one embodiment, the controller also controls power factor correction of the power control/lighting system. In at least one embodiment, the controller provides dimming information based on the phase control dimming signal that allows the lamp ballast to be used in conjunction with a phase control dimmer.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: October 6, 2015
    Assignee: Cirrus Logic, Inc.
    Inventors: William A. Draper, Robert Grisamore
  • Patent number: 9148917
    Abstract: A load driving device includes a switch element configured to generate an output voltage to a load from an input voltage depending on an ON/OFF operation thereof, a switch controller configured to control the ON/OFF operation of the switch element such that a feedback voltage obtained by subtracting a dropped voltage of the load from the output voltage and a predetermined reference voltage are maintained to be consistent, and a variable current source configured to perform ON/OFF controlling of a driving current flowing to the load in response to a driving current control signal. When the switch element is in an ON state at an OFF timing of the driving current, the switch controller maintains the switch element in the ON state thereafter, and turns off the switch element when the ON period of the switch element reaches a predetermined period.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: September 29, 2015
    Assignee: Rohm Co., Ltd.
    Inventors: Masaki Omi, Fumihiko Terasaki
  • Patent number: 9125266
    Abstract: An LED driver for controlling a current supplied to an LED fixture, the LED driver including a switched mode power supply (SMPS) for providing the current to the LED array and a control unit for controlling a switch of the SMPS. The control unit includes an input terminal connected to a current sensing circuit and the switch is connected to the LED fixture at a node downstream of the LED fixture. The current sensing circuit of the LED driver provides a feedback signal to the input terminal of the control unit; the current sensing circuit including a current sensor arranged to provide, when the switch is closed, the feedback signal representing a level of the current supplied to the LED fixture; the current sensing circuit further providing the feedback signal indicating a zero-crossing of the current supplied to the LED fixture when the switch is open.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: September 1, 2015
    Assignee: ELDOLAB HOLDING B.V.
    Inventors: Petrus Johannes Maria Welten, Kevin Lambertus Hubertus Salden
  • Patent number: 9123298
    Abstract: A display apparatus is provided. The display apparatus includes a display panel which displays an image, a LED module which provides backlight to the display panel, a LED driving unit which selectively uses current of an inductor to apply driving voltage to the LED module, a sensing unit which senses a current value of the inductor, and a switching control unit which adjusts the driving voltage according to sensing result by the sensing unit.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: September 1, 2015
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Tae-sung Kim, Jeong-il Kang, Young-soo Kim, Gil-yong Chang
  • Patent number: 9119238
    Abstract: A method for driving an LED connected to a power switch is provided. The method includes: determining a duty cycle of a pulse sequence for controlling the power switch according to a present current and a predetermined operating current of the LED; generating the pulse sequence according to the duty cycle and according to at least one of a randomized period sequence and a randomized pulse position sequence; and controlling switching operation of the power switch by the pulse sequence, so as to drive the LED. An apparatus for driving a light emitting diode, an apparatus for dimming a light emitting diode and illumination systems are also provided.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: August 25, 2015
    Assignee: OSRAM GmbH
    Inventors: Yang Hu, LiBo Wu
  • Patent number: 9111743
    Abstract: A filament preheat module for preheating a filament of a lamp powered by a power circuit including an inverter, the inverter comprising an inductively coupled conductor, an inductively coupled conductor of the filament preheat module magnetically coupled to the inductively coupled conductor of the inverter to power the filament during preheating, and a switching circuit configured to electrically connect the power from the inductively coupled conductor of the filament preheat module to the filament. The switching module is configured to cutoff the power to the filament from the filament preheat module after a predetermined time period during preheating.
    Type: Grant
    Filed: November 4, 2013
    Date of Patent: August 18, 2015
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Fanbin Wang, Youmin Zhang, Hongbin Wei
  • Patent number: 9112354
    Abstract: A process instrument includes a transducer, a two wire interface, a microprocessor, a digital to analog converter, a first control circuit, and a second control circuit. A current passing through the two wire interface indicates a condition of the transducer. The microprocessor is interfaced with the transducer. The digital to analog converter receives a signal from the microprocessor indicating a current value. The first control circuit is coupled to the digital to analog converter and adapted to control the current passing through the two wire interface to the current value. The second control circuit is coupled to the digital to analog converter and supplies current to a secondary load.
    Type: Grant
    Filed: February 15, 2013
    Date of Patent: August 18, 2015
    Assignee: Rosemount Inc.
    Inventor: Douglas Wayne Arntson
  • Patent number: 9093032
    Abstract: Systems and methods for inaudible enhanced pulse width modulation (PWM) backlight dimming are provided. By way of example, an electronic display backlight system according to the present disclosure may include a backlight element and backlight driver circuitry. The backlight driver circuitry may drive the backlight element at various brightness levels using at least two individual duty cycles that occur immediately after one another. The backlight driver circuitry may vary the individual duty cycles such that none will ever reach 100% unless all are 100%, thereby preventing the occurrence of audible noise that might otherwise arise if an “on” PWM period from one individual duty cycle continued into the next.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: July 28, 2015
    Assignee: APPLE INC.
    Inventors: Asif Hussain, Manisha P. Pandya
  • Patent number: 9086435
    Abstract: Circuits for sensing current levels within an apparatus are disclosed. In specific cases, a constant voltage power supply is used to power an LED lighting apparatus in which there are uncertainties within the forward voltages of the LEDs, which in turn creates uncertainty with respect to the current level flowing through the LEDs. To manage these uncertainties, the current flowing through the LEDs is measured by determining a voltage level across a known resistor and calculating the current level. To prevent the known resistor from causing a significant reduction in the efficiency of the overall light engine, the circuit includes one or more transistors in parallel with the known resistor to reduce the effective resistance in the LED circuit during times that the current is not being sensed.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: July 21, 2015
    Assignee: ARKALUMEN INC.
    Inventor: Gerald Edward Briggs
  • Patent number: 9084316
    Abstract: A lighting system includes one or more methods and systems to control dissipation of excess power in the lighting system when the power into a switching power converter from a leading edge, phase-cut dimmer is greater than the power out of the switching power converter. In at least one embodiment, the lighting system includes a controller that controls dissipation of excess energy in the lighting system to prevent a premature disconnection of the phase-cut dimmer. In at least one embodiment, the controller actively controls power dissipation by generating one or more signals to actively and selectively control power dissipation in the lighting system. By actively and selectively controlling power dissipation in the lighting system, the controller intentionally dissipates power when the power into the lighting system should be greater than the power out to a lamp of the lighting system.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: July 14, 2015
    Assignee: Cirrus Logic, Inc.
    Inventors: John L. Melanson, Eric J. King
  • Patent number: 9059641
    Abstract: A fault mode of a PWM module embedded in a microcontroller is used to detect main supply zero crossings for regulating output voltage of a PFC converter operating in BCM, without using an external detecting element or a comparator, ADC or other specialized component internal to the microcontroller. In some implementations, the end of decrease current flow in the energy storage inductor of the converter is used to reinitialize a PWM timer or counter (counting-up or counting-down timer). The current goes to zero for a time period when the main supply voltage goes to zero, resulting in the PWM timer or counter not being reinitialized prior to the end of the current PWM cycle. The failure to reinitialize the timer or counter can be used to generate a signal indicative of a zero voltage crossing of the main supply voltage.
    Type: Grant
    Filed: July 5, 2011
    Date of Patent: June 16, 2015
    Assignee: Atmel Corporation
    Inventor: Karl Jean-Paul Courtel
  • Patent number: 9041314
    Abstract: A power supply topology is used in which a transistor is provided on the side of an output node of a rectifying circuit. An inductor is provided on the side of a reference node, a resistor is inserted between the transistor and the inductor, and one end of the resistor is coupled to a ground power supply voltage of a PFC circuit. The PFC circuit includes a square circuit which squares a result of multiplication of an input voltage detection signal and feedback information (output voltage of an error amplifier circuit). The PFC circuit drives on the transistor when a detection voltage developed at the resistor reaches zero, and drives off the transistor when the detection signal reaches an output signal of the square circuit.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: May 26, 2015
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Ryosei Makino, Kenichi Yokota, Tomohiro Tazawa
  • Patent number: 9041305
    Abstract: Representative embodiments of the invention provide a system, apparatus, and method of controlling an intensity and spectrum of light emitted from a solid state lighting system. The solid state lighting system has a first emitted spectrum at a full intensity level and at a selected temperature, with a first electrical biasing for the solid state lighting system producing a first wavelength shift, and a second electrical biasing for the solid state lighting system producing a second, opposing wavelength shift. Representative embodiments provide for receiving information designating a selected intensity level or a selected temperature; and providing a combined first electrical biasing and second electrical biasing to the solid state lighting system to generate emitted light having the selected intensity level and having a second emitted spectrum within a predetermined variance of the first emitted spectrum over a predetermined range of temperatures.
    Type: Grant
    Filed: April 8, 2014
    Date of Patent: May 26, 2015
    Assignee: Point Somee Limited Liability Company
    Inventors: Anatoly Shteynberg, Harry Rodriguez, Bradley M. Lehman, Dongsheng Zhou
  • Patent number: 9041310
    Abstract: A load driving apparatus related to light emitting diodes (LED) is provided. The load driving apparatus includes a power conversion circuit, a complex function circuit, and a control chip. The power conversion circuit receives a DC input voltage and provides a DC output voltage to at least one LED string in response to a gate pulse-width-modulation (PWM) signal. The complex function circuit is serially connected with the LED string and provides a short-protection mechanism. The control chip is coupled to the power conversion circuit and the complex function circuit. The control chip generates the gate PWM signal to control the operation of the power conversion circuit, and when the LED string is short-circuited, the control chip controls the complex function circuit to activate the short-protection mechanism, so as to protect the load driving apparatus from being damaged.
    Type: Grant
    Filed: July 19, 2013
    Date of Patent: May 26, 2015
    Assignee: Beyond Innovation Technology Co., Ltd.
    Inventors: Chiu-Yuan Lin, Chien-Pang Hung, Zhen-Chun Liu
  • Patent number: 9035565
    Abstract: The invention relates to a method for operation of an actively clocked PFC circuit with a directly or indirectly connected load circuit at the output of the PFC circuit, wherein the load circuit has a lighting means, in particular one or more LEDs, wherein the PFC circuit is supplied at least with a measurement signal which reflects the power consumption of the load circuit or with an external control signal which indicates the power consumption, and a control circuit adjusts the mode of operation of the PFC circuit continuously or preferably in two or more steps, depending on the control signal or measurement signal.
    Type: Grant
    Filed: November 13, 2009
    Date of Patent: May 19, 2015
    Assignee: Tridonic GmbH & Co. KG
    Inventors: Michael Zimmermann, Dominique Combet
  • Patent number: 9030124
    Abstract: A lighting system and method are provided for controlling a PWM duty cycle. The lighting system is provided with at least one device that is configured to emit light in response to receiving electrical power. The lighting system includes a power circuit and a feedback circuit. The power circuit is configured to selectively supply power to the device at a duty cycle corresponding to a first mode and a second mode, wherein the duty cycle of the first mode is less than 10% of the duty cycle of the second mode. The feedback circuit is configured to provide a feedback signal that is indicative of the energy provided to the device. The power circuit is further configured to disable power to the device during the first mode in response to the energy being greater than a threshold energy value, thereby adjusting the duty cycle.
    Type: Grant
    Filed: January 30, 2013
    Date of Patent: May 12, 2015
    Assignee: North American Lighting, Inc.
    Inventors: Kenneth Wayne Schoel, Daniel Robert Edwards, Manuel Saldana de Leon
  • Patent number: 9030106
    Abstract: A driving circuit for a LED backlight module includes a brightness adjusting module, a current detector, a reference voltage adjusting module, and a comparing module. The current detector is capable of detecting the current of the brightness adjusting module and outputting a detecting result. The reference voltage adjusting module is capable of choosing the corresponding reference voltage corresponding to the detecting result of the current detector. Thus, the reference voltage outputted to the comparing module can be adjusted according to the change of the current of the brightness adjusting module. This reduces the power consumption and the amount of heat generated due to the power consumption, and improves the performance of the LED backlight module.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: May 12, 2015
    Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd.
    Inventor: Fei Li