Periodic Switch Cut-out Patents (Class 315/225)
  • Patent number: 10804835
    Abstract: A controller controls a first inverter drive circuit and a second inverter drive circuit. The first inverter drive circuit drives a load having a load current larger than the second inverter drive circuit. The first inverter drive circuit includes a control ground terminal and a drive ground terminal which are isolated from each other. The ground terminal of the second inverter drive circuit is connected to the ground of the controller. The control ground terminal of the first inverter drive circuit is connected to the ground of the controller. The drive ground terminal of the first inverter drive circuit is connected to the negative side of the first inverter circuit.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: October 13, 2020
    Inventors: Shinya Fukuda, Takashi Oishi, Toru Nakai
  • Patent number: 10701779
    Abstract: The present invention relates to a drive device for an illuminating load, an illumination device, a lighting system and a method for controlling the lighting system, wherein the drive device is connected between the illuminating load and a power adapter device for power supply, wherein the drive device comprises a control unit, wherein the control unit is configured to adjust the impedance of the drive device according to an electric output signal measured from the illuminating load so as to accordingly adjust the output voltage of the power adapter device and thereby to adjust the electric output signal for the illuminating load.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: June 30, 2020
    Assignee: LEDVANCE GMBH
    Inventors: Daxin Lin, Xusheng Yang
  • Patent number: 10616968
    Abstract: Light output from an LED light source is increased or reduced in response to adjustment of a triac-based dimmer having a triac holding current to maintain conduction of the dimmer. An LED controller to control the light output includes a voltage-controlled impedance to provide an adaptive holding current that causes a triac current of the dimmer to be greater than the triac holding current, particularly when the dimmer is adjusted for significantly low light output (e.g., less than 5%, 2%, or 1% of full power light output). The adaptive holding current also allows for smooth increase of the light output starting from low light output, without perceivable flicker or shimmer. In one example, the voltage-controlled impedance is a resistive-like impedance that is placed on a secondary side of a transformer providing power to the LED light source. In another example, the voltage-controlled impedance is not pulse width modulated.
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: April 7, 2020
    Assignee: DMF. Inc.
    Inventor: Jie Dong Wang
  • Patent number: 10236680
    Abstract: In a control circuit of a switching power supply device, a switching cycle generating unit controls a switching cycle in keeping with a signal of an error voltage detected on a secondary side to stabilize an output voltage at a target value. A load current for overload protection is estimated based on a value produced by integrating a resonant current at an integrator and averaging at an averaging calculation unit. Here, although the switching cycle is correlated to the ratio of input/output voltages, the switching cycle is negatively correlated to the input voltage because the output voltage is controlled so as to be constant. A correction calculating unit uses a signal that decides the switching cycle as information corresponding to the input voltage, which eliminates the need to detect the input voltage.
    Type: Grant
    Filed: July 27, 2017
    Date of Patent: March 19, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventor: Tetsuya Kawashima
  • Patent number: 9759554
    Abstract: A projector panel includes pixel display, a display controller, and a pattern generator. The pattern generator is operative to output pixel data indicative of at least one application specific predetermined pattern. In a particular embodiment, the projector panel is a liquid-crystal-on-silicon panel. In another particular embodiment, the projector panel is adapted for selective use in either structured light projection systems or conventional video projection systems.
    Type: Grant
    Filed: August 2, 2013
    Date of Patent: September 12, 2017
    Assignee: OmniVision Technologies, Inc.
    Inventors: Sunny Yat-san Ng, Manuel Lu
  • Patent number: 9497851
    Abstract: A lighting system includes a controller that is configured to provide thermal management for the lighting system by distributing excess energy in the lighting system through multiple power dissipation circuits. In at least one embodiment, the lighting system is a phase cut compatible, dimmable lighting system having one or more light sources selected from a group consisting of at least one light emitting diode and at least one compact fluorescent lamp. In at least one embodiment, the controller is configured to control the plurality of power dissipation circuits in accordance with a thermal management strategy to dissipate the excess energy in the phase cut compatible, dimmable lighting system. The particular thermal management strategy is a matter of design choice. The power distribution circuits include two of more of: a controlled switch path power dissipation circuit, a controlled link path power dissipation circuit, and a controlled flyback path power dissipation circuit.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: November 15, 2016
    Inventors: John L. Melanson, Eric J. King
  • Patent number: 9481166
    Abstract: Provided are a piezoelectric element drive circuit and state detection method, and an image recording device which realize state detection of a piezoelectric element inexpensively and with a suppressed circuit scale in a drive circuit for rapidly driving a large-capacity load that uses negative voltage drive. An output potential (VOUT) of a boost unit (BST) is detected in a state in which VS_AMP supplied to an amplification unit (AMP) is set to a voltage lower than a maximum rating of a transistor (FET1) by SW1, supply of VS_FET to the boost unit (BST) is blocked by SW2, and an individual electrode (28) of a piezoactuator (30) is pulled down to VS_FET via a resistor (R6).
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: November 1, 2016
    Assignee: FUJIFILM Corporation
    Inventor: Atsuko Hirakawa
  • Patent number: 9413325
    Abstract: A cable modem is provided in a premises. The cable modem is operated in a first mode with a first upstream passband. At least one fusible link in the cable modem is caused to be blown, which in turn causes the cable modem to upgrade to a second mode with a second upstream passband, greater than the first upstream passband, without use of any switch.
    Type: Grant
    Filed: July 1, 2014
    Date of Patent: August 9, 2016
    Inventors: Paul Brooks, Belal Hamzeh
  • Patent number: 9371030
    Abstract: A control circuit is configured to compare an input voltage measured through an input voltage detection circuit with a first threshold which is lower than a rated voltage of an external DC power supply and with a second threshold which is lower than the first threshold. The control circuit is configured, when detecting that a duration time in which the input voltage is kept lower than the first threshold reaches a predetermined holding period, to stop operating a switching device. The control circuit is configured, after detecting that the input voltage is lower than the second threshold, to more shorten a maximum ON time than that during a normal operation or lengthen an OFF time of the switching device than a maximum OFF time during the normal operation.
    Type: Grant
    Filed: May 8, 2015
    Date of Patent: June 21, 2016
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventor: Takahiro Fukui
  • Patent number: 9345118
    Abstract: Apparatus and methods for detecting lamp failure in a rapid thermal processing (RTP) tool are provided. Lamp failure detection systems are provided that can accommodate DC and/or AC voltages. The systems sample voltage signals along a circuit path formed by at least two serially connected lamps, calculate a voltage drop across the first lamp of the at least two serially connected lamps based on the sampled voltage signals, and determine whether a lamp failure has occurred based on a relationship between the voltage drop across the first lamp and a total voltage applied to the circuit path.
    Type: Grant
    Filed: November 4, 2014
    Date of Patent: May 17, 2016
    Inventors: Oleg Serebryanov, Alexander Goldin
  • Patent number: 9320099
    Abstract: An LED array switching apparatus, comprises: a plurality of LED segments D1 to Dn connected in series, each LED segment having a forward voltage; a voltage supply coupled to the plurality of LED segments; and a plurality of constant current sources G1 to Gn, coupled to outputs of LED segments D1 to Dn, respectively. Each of the constant current sources is switchable between a current regulating state and an open state such that as the voltage of the voltage supply increases, LED segments are switched on and lit to form a higher forward voltage LED string, and as the voltage of the voltage supply decreases, segments are switched off and removed from the LED string starting with the most recently lit segment.
    Type: Grant
    Filed: May 20, 2013
    Date of Patent: April 19, 2016
    Assignee: Huizhou Light Engine Ltd.
    Inventors: Wa Hing Leung, Johnny Siu
  • Patent number: 9270163
    Abstract: A power source includes a rectifying unit configured to full-wave rectify an AC voltage to be input, a first and second converter configured to convert the voltage rectified by the rectifying unit, a zero cross detection unit configured to detect a zero cross of the AC voltage, a voltage detection unit configured to detect the AC voltage, a first capacitance element connected across a potential after being subjected to rectification by the rectifying unit and a ground, a first discharging resistor configured to discharge electric charges charged in the first capacitance element, a first switch unit configured to cut off a current flowing to the first discharging resistor and a stopping unit configured, in a case where the AC voltage is detected by the voltage detection unit and the detected voltage is smaller than a threshold value, to stop the operation of the second converter.
    Type: Grant
    Filed: January 29, 2013
    Date of Patent: February 23, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yasuhiro Shimura
  • Patent number: 9236729
    Abstract: Anti-arcing circuits are described herein that are configured to prevent or substantially mitigate arcing when a power adapter is connected/disconnected from a client device. The anti-arcing circuit restricts power supplied when a connection of a connector of a power adapter to the adapter interface is not fully established. The anti-arcing circuit is further configured to detect when a connection is made and remove the restriction to supply power for operations of the client device. In one approach, the anti-arcing circuit includes two different paths and components associated with a detection mode and operational mode respectively. In the detection mode, power supply is suppressed and a current pulse may be sent to determine if a connection is established. If current is detected, a switch is made to operational mode and power for normal device operations is supplied.
    Type: Grant
    Filed: August 15, 2013
    Date of Patent: January 12, 2016
    Assignee: Microsoft Technology Licensing, LLC
    Inventors: Chee Kiong Fong, Suet Fong Tin, David Richard Perchilk, Edward C. Giaimo, III, Michael Donovan Rulien, Perry Samuel Stultz
  • Patent number: 9220160
    Abstract: Control unit decreases power to be supplied to high-pressure discharge lamp when an output voltage or an output current for high-pressure discharge lamp measured by measurement unit is in an abnormal range. Drive unit driving switching element includes capacitor that supplies, to a control electrode of switching element disposed on high potential side, electric charge necessary for turning on switching element disposed on high potential side when switching element disposed on low potential side is turned off. When high-pressure discharge lamp is started up, a discharge lamp lighting device starts to charge capacitor before DC/DC converter is started to operate, and control unit has a determination period for determining presence/absence of an abnormality based on a measured value acquired by measurement unit in a state in which DC/DC converter and DC/AC inverter are operated after completion of charging of capacitor.
    Type: Grant
    Filed: October 17, 2013
    Date of Patent: December 22, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Masahiro Nishikawa, Masatoshi Ueno, Kazuya Kato, Masashi Kichima
  • Patent number: 9210783
    Abstract: An electronic ballast and startup method including an electronic ballast operably connected to a lamp having a lamp filament, the electronic ballast having a timer (110) generating an inverter control signal (112) and a preheat control signal (114); a converter (120) receiving AC power and generating DC power (122); a self-oscillating inverter (130) receiving DC power (122) and being operable to provide lamp power (132) to the lamp, the self-oscillating inverter (130) being responsive to the inverter control signal (112); and a filament preheater (140) receiving DC power (122) and being operable to provide filament power (142) to the lamp filament, the filament preheater (140) being responsive to the preheat control signal (114). When AC power is initially applied, preheat control signal (114) directs the filament preheater (140) to provide filament power (142), and inverter control signal (112) directs the self-oscillating inverter (130) not to provide lamp power (132).
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: December 8, 2015
    Inventors: Yuhong Fang, Sree Venkit, Sanjaya Kumar Pradhan, Alejandro Lopez, George Grouev, Arun Ganesh, Bruce Rhodes
  • Patent number: 9161422
    Abstract: An electronic ballast for driving a gas discharge lamp includes an EMI filter, a bridge rectifier coupled to a DC bus without a conventional electrolytic capacitor, a passive valley fill circuit built as a network having 4 charge/discharge energy storage capacitors and 9 diodes (4C9C), and a resonant DC to AC high frequency inverter for powering gas discharge lamp. The 4C9D circuit divides the rectified peak voltage by four and the low output voltage of the circuit is used to provide continuous lamp operation. The result is a ballast having substantially improved power factor, total harmonic distortion, and current crest factor. The electronic ballast is provided with a dimming capability from a TRIAC based wall dimmer.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: October 13, 2015
    Assignee: Lucidity Lights, Inc.
    Inventor: Felix I. Alexandrov
  • Patent number: 9119273
    Abstract: A compact fluorescent lamp (CFL) ballast driver includes first, second and neutral AC voltage terminals, a full wave rectifier between the first AC voltage terminal and the neutral AC input terminal, and a separate branch between the second AC voltage terminal and the neutral AC input terminal. A resonator circuit includes at least two inductors and provides its output voltage to a CFL lamp. The driver includes a first state detector circuit to monitor the first AC voltage terminal, and a second state detector circuit to monitor the second AC voltage terminal. The first and second state detector circuits activate respective first and second switches. The first switch shunts one inductor of the resonator circuit, and the second switch shunts another inductor of the resonator circuit. The driver can be housed in a CFL having a capper, a three-way lamp base adjacent to the capper and an arc tube.
    Type: Grant
    Filed: November 25, 2013
    Date of Patent: August 25, 2015
    Inventors: Jácint Gergely, Gábor Szabó, Loránd Lehel Tóth, Lajos Csibi, Tamás Vásárhelyi
  • Patent number: 9089022
    Abstract: A light adjusting device for adjusting the luminance of a light source is provided. The light adjusting device comprises a rectifier module, a first switch element, a second switch element and a control module. The rectifier module receives an AC signal from a first power node and a second power node, and rectifies the AC signal to output a driving signal to the light source. The first switch element is coupled to the first power node. The second switch element is coupled to the second power node. The control module outputs a control signal to the first and second switch elements to control the conduction states of the first and second switch elements. When the first and second switch elements are turned on, the driving signal provided to the light source is interrupted.
    Type: Grant
    Filed: February 13, 2014
    Date of Patent: July 21, 2015
    Inventor: Po-Shen Chen
  • Patent number: 9030107
    Abstract: An illumination apparatus includes: a series circuit of a thyristor and at least one load circuit connected across an AC power source; a current control circuit for adjusting an input current to be maintained at a predetermined level during a part or the whole of an ON period of the thyristor; and a short circuit for short-circuiting input ports of the load circuit to have a predetermined resistance during a part of the ON period of the thyristor and a part or the whole of an OFF period of the thyristor. The current control circuit and the short circuit are connected in parallel to the load circuit.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: May 12, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventor: Shigeru Ido
  • Patent number: 9006979
    Abstract: The present invention provides a protection circuit with low energy-consumption and a driving circuit thereof. The protection circuit includes a detection circuit and a switch circuit. The switch circuit is disposed between a power supply circuit and a peripheral step-down shunt. The detection circuit and the switch circuit are connected for controlling. The switch circuit includes a PNP triode or a P MOS transistor connected between the power supply circuit and the peripheral step-down shunt. A base of the PNP triode or the P MOS transistor is connected to a drain of another N MOS transistor through a resistor, and a gate of the N MOS transistor is connected to a status pin of the detection circuit. The present invention solves drawbacks of existent input voltage after the circuit entering a protection state causing unnecessary energy-consumption in peripheral small-signal circuit and voltage-dividing resistors.
    Type: Grant
    Filed: June 25, 2013
    Date of Patent: April 14, 2015
    Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd
    Inventor: Hua Zhang
  • Patent number: 8957591
    Abstract: An illumination system includes a lighting apparatus having a solid-state light emitting element as a light source; and a dimmer including a bidirectional switching element having a self-sustaining function and connected to a serial circuit of the lighting apparatus and an external power source. The dimmer varies a conduction angle of the bidirectional switching element by controlling a phase of an AC voltage of the external power source, wherein the lighting apparatus performs dimming of the light source based on the conduction angle of the bidirectional switching element, and the dimmer continues to apply driving current to the bidirectional switching element during a first period, which is a part of a second period, the bidirectional switching element being allowed to conduct throughout the second period.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: February 17, 2015
    Assignee: Panasonic Corporation
    Inventors: Yoshinobu Murakami, Koji Nakagawara, Masahito Ohnishi, Masahiro Naruo, Shigeru Ido, Kazuhiro Nisimoto, Hiromitsu Mizukawa
  • Patent number: 8941326
    Abstract: An Alternating-current-Direct-current (AC-DC dual-use) Light Emitting Diode (LED) driving circuit includes an input power circuit, a buck-boost converter, and a Pulse Width Modulation (PWM) signal controller. The buck-boost converter, including a switching transistor and a feedback resistor, receives a current signal output from the input power circuit, and drives an LED with a driving signal. The PWM signal controller outputs a PWM signal according to the driving signal, so as to sequentially turn on and turn off the switching transistor. One end of the feedback resistor is coupled to the LED, and a floating ground terminal of the PWM signal controller is coupled to the switching transistor and the other end of the feedback resistor. Therefore, the AC-DC dual-use LED driving circuit is capable of dynamically adjusting the duty ratio of the PWM signal without connecting an external photocoupler.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: January 27, 2015
    Assignee: Macroblock, Inc.
    Inventors: Yan-Cun Li, Hsing-Fu Liu, Jui-Chi Chang, Po-Yao Yeh
  • Patent number: 8941319
    Abstract: An LED constant-current drive circuit includes a BUCK circuit consisting of a transformer T1, a diode D9, a capacitor C5 and a field effect transistor Q1; a voltage limiting circuit consisting of a resistor R1, a diode D8, a capacitor C1, a resistor R3, a triode Q2, a zener diode DZ1 and a diode D10; and a current limiting circuit consisting of a resistor R4, a triode Q3, a triode Q4 and a resistor R2. When the transistor Q1 is turned on, a current flows through a primary side of the transformer T1 and an LED load, and then flows through the transistor Q1 and the resistor R2, and then flows back to a negative electrode of a power supply. When the transistor Q1 is turned off, the current flows through the primary side of the transformer T1, the LED load and the diode D9, thus forming a loop.
    Type: Grant
    Filed: February 13, 2012
    Date of Patent: January 27, 2015
    Assignee: Shenzhen Fuxinya Technology Development Co., Ltd
    Inventors: Yuan Gao, Yubo Qiao
  • Patent number: 8928241
    Abstract: A circuit for driving a light emitting diode (LED) comprises: an alternating voltage power supply, comprising a triac dimmer having a firing angle and output terminals that provide power to the LED; a zero crossing detector that detects a polarity change of the alternating voltage provided by the alternating voltage power supply and provides a zero crossing output signal indicative of the zero crossing; a timer triggered by the zero crossing output signal that generates a timer output signal during a time period of the timer; and LED power circuitry that reduces current to the light emitting diode based upon timing characteristics of the timer output signal.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: January 6, 2015
    Assignee: Huizhou Light Engine Ltd.
    Inventors: Chung Ping Kevin Lo, Kwok Hung Poon, Wa-Hing Leung, Kam Wah Siu
  • Patent number: 8901852
    Abstract: An LED bulb is described, comprising LEDs within a shell and a driver circuit to operate the LEDs at a plurality of brightness levels. The driver circuit comprises first and second inputs to receive AC, a neutral input, a converter circuit, first and second rectifier circuits, a detector circuit, and a processing circuit. The first rectifier circuit is connected to the first and neutral inputs and rectifies the AC received. The second rectifier circuit is connected to the second and neutral inputs and rectifies the AC received. The detector circuit is connected to the first and second rectifier circuits. The processing circuit has a first and a second processor input, and is connected to the detector circuit. The processing circuit produces a chop signal with a duty cycle based on whether the first or second input is hot. The converter circuit powers the LEDs based on the chop signal.
    Type: Grant
    Filed: May 2, 2013
    Date of Patent: December 2, 2014
    Assignee: Switch Bulb Company, Inc.
    Inventor: Rolf Wendt
  • Patent number: 8890429
    Abstract: A solid-state light-emitting element drive device includes a switching regulator and a control circuit. The switching regulator includes a series circuit of a switching element and an inductor, a regenerative element configured to allow a regenerative current to flow therethrough from the inductor when the switching element is turned off, and output terminals configured so that a solid-state light-emitting element is connected therebetween. The control circuit is configured to control a switching operation of the switching element of the switching regulator. The control circuit is configured to suppress an output power of the switching regulator if a parameter obtained from at least one of an ON-period and an OFF-period of the switching element is out of a prescribed range.
    Type: Grant
    Filed: September 10, 2013
    Date of Patent: November 18, 2014
    Assignee: Panasonic Corporation
    Inventors: Kenichi Fukuda, Masahiro Naruo, Sana Esaki
  • Patent number: 8866386
    Abstract: A direction indication lamp control device includes: a current control element including an end which outputs a drive current having a magnitude corresponding to amplitude of a pulse signal; a current clamp unit which limits the drive current to a current upper limit value; a voltage clamp unit which limits a reference voltage to a voltage upper limit value; and a wire disconnection detection unit which outputs a wire disconnection detection signal in a case where the drive current corresponding to the pulse wave of the pulse signal is equal to or less than a wire disconnection detection value, or in a case where the reference voltage is equal to the voltage upper limit value. The current upper limit value is smaller than the drive current flowing through a direction indication lamp when the reference voltage is the voltage upper limit value.
    Type: Grant
    Filed: October 31, 2011
    Date of Patent: October 21, 2014
    Assignee: Shindengen Electric Manufacturing Co., Ltd.
    Inventors: Kenichi Kubota, Hideyuki Ono
  • Patent number: 8847498
    Abstract: A driver circuit for driving an LED includes a rectifier circuit to receive AC voltage and to convert the AC voltage to DC voltage. The driver circuit further includes a filter circuit for filtering the DC voltage. The driver circuit further includes a detection circuit for determining a change in the filtered DC voltage over a predetermined time interval. The driver circuit further includes a dampening circuit for dampening the filtered DC voltage responsive to the detection circuit determining that the change in filtered DC voltage over the predetermined time interval exceeds a predetermined threshold.
    Type: Grant
    Filed: May 16, 2012
    Date of Patent: September 30, 2014
    Assignee: Technical Consumer Products, Inc.
    Inventors: Timothy Chen, Haiyan Wang
  • Patent number: 8847505
    Abstract: The invention discloses an illumination control circuit and an illumination control method. The illumination control method includes modulating an alternating current input signal and accordingly generating a dimming signal, which includes several waveform pulses each with an adjustable conduction angles; continuously sampling the waveform pulses of the dimming signal and forming an average waveform pulse from the sampled waveform pulses; extracting the average waveform pulse, which has an average conduction angle corresponding to the conduction angles of the waveform pulses; performing an integration on the sampled average waveform pulse and accordingly generating a current-controlling signal; and driving an illumination lamp according to the current-controlling signal.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: September 30, 2014
    Assignee: Lextar Electronics Corporation
    Inventors: Po-Shen Chen, Chun-Kuang Chen, Feng-Ling Lin, Hui-Ying Chen
  • Patent number: 8803434
    Abstract: A power supply has a TRIAC dimmer, and an AC-DC converter connected to the TRIAC dimmer. The AC-DC converter has a power switch, a bleed switch, and a controller. The controller turns off the bleed switch in a first time duration and turns on the bleed switch in a second time duration. Magnitude of a current of the power switch in the first time duration is larger than magnitude of a current of the power switch in the second time duration. Magnitude of a current of the bleed switch in a third time duration within the second time duration is smaller than magnitude of a current of the bleed switch in a fourth time duration within the second time duration.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: August 12, 2014
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Seung Woo Hong, Gye-Hyun Cho, Young-Je Lee, Jae-yong Lee
  • Patent number: 8779674
    Abstract: This invention provides an integrated power supply for a controller of an electronic ballast for a fluorescent lamp. The integrated power supply couples output power from the electronic ballast and uses the coupled power to provide power to the controller. In one embodiment, the electronic ballast may include a rectifier for converting an alternating current input voltage into a direct current output voltage, and a circuit including a combined power factor correction (PFC) stage and an inverter, wherein the PFC stage and the inverter share a switch. Also provided is a controller for an electronic ballast. The controller may include a voltage mode or current mode duty ratio controller that controls a duty ratio of a switch of the ballast. The controller and the ballast allow dimming of the fluorescent lamp while maintaining a high power factor.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: July 15, 2014
    Inventors: John Lam, Praveen Jain
  • Patent number: 8773031
    Abstract: Various embodiments of a dimmable power supply are disclosed herein. For example, some embodiments provide a dimmable power supply including an input current path, a switch in the input current path, an energy storage device connected to the input current path, a load output connected to the energy storage device, and a timer-based variable pulse generator connected to a control input of the switch. The timer-based variable pulse generator is adapted to generate a stream of pulses having a variable on-time and off-time. The dimmable power supply is adapted to vary the on-time and off-time to control a current at the load output.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: July 8, 2014
    Assignee: InnoSys, Inc.
    Inventors: Laurence P. Sadwick, William B. Sackett, Michael D. Brady
  • Patent number: 8766557
    Abstract: Various embodiments of the invention provide power factor correction in solid state lighting applications. In certain embodiments, an LED driver for an LED array is controlled for power factor correction by a control circuit block. The control circuit block comprises electronic circuitry that enables the input current to the LED driver to be measured and controlled. This control circuit block comprises at least one switching device that enables an alternating form of current at a particular frequency to be applied to the LED array regardless of whether the main power source is a DC or AC power source.
    Type: Grant
    Filed: November 7, 2011
    Date of Patent: July 1, 2014
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Suresh Hariharan
  • Patent number: 8729817
    Abstract: A ballast including a latching circuit is provided. The ballast includes an inverter circuit for providing an oscillating voltage signal to energize a lamp set, a control circuit for controlling operation of the inverter circuit, and a voltage supply circuit for providing a supply voltage to the control circuit. The ballast also includes a fault detection circuit for detecting a fault condition and a latching circuit connected to the fault detection circuit. The latching circuit is configured to drain the supply voltage and thereby disable the control circuit so that operation of the inverter circuit is discontinued during a fault condition.
    Type: Grant
    Filed: October 23, 2012
    Date of Patent: May 20, 2014
    Assignee: OSRAM SYLVANIA Inc.
    Inventors: Ashwani Guleria, Ashish Kumar Gupta
  • Patent number: 8710766
    Abstract: Provided is an LED driving circuit (4), including: an impedance detecting section (7) for detecting an impedance value of a phase-control type dimmer (2); and an impedance adjusting section (6) for adjusting an impedance of the LED driving circuit (4) based on the impedance value detected by the impedance detecting section (7).
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: April 29, 2014
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Atsushi Kanamori, Hirohisa Warita, Takeshi Murata
  • Patent number: 8704463
    Abstract: A temperature control method for light emitting diode (LED) is disclosed, and the method comprises the following steps: acquiring the present temperature of the LED during the light emission of the LED; obtaining a driving electric current corresponding to the present temperature based on the present temperature of the LED; and driving the LED based on the driving electric current. This invention further discloses a temperature control device for the LED and a liquid crystal display.
    Type: Grant
    Filed: November 17, 2011
    Date of Patent: April 22, 2014
    Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd
    Inventors: Poshen Lin, Liangchan Liao, Xiang Yang
  • Patent number: 8664873
    Abstract: A method is provided for operating at least one LED by a switched-mode regulator circuit to which a DC or a rectified AC voltage is supplied and which provides a supply voltage for at least one LED by a coil and a switch clocked by a control/regulation unit. When the switch is activated, power is temporarily stored in the coil and is discharged through a diode and through at least one LED when the switch is deactivated and the current flows through the LED through a first power storage element which is coupled to a second power storage element. The first power storage element just reaches its maximum capability of storing power due to the current flowing through the LED. A rising current is supplied to the second power storage element such that the time can be detected when the first power storage element recovers its capability of storing power.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: March 4, 2014
    Assignee: Tridonic GmbH & Co KG
    Inventors: Stefan Zudrell-Koch, Michael Zimmermann
  • Patent number: 8664885
    Abstract: A circuit for connecting to a dimmer, the circuit configured to receive an input signal from the dimmer. The circuit comprises a first load and a switch. The switch is operable to automatically engage the first load at a predetermined time from a zero-crossing of the input signal and automatically disengage the first load at other times.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: March 4, 2014
    Assignee: NXP B.V.
    Inventors: Gert-Jan Koolen, Victor Zwanenberg, Jochem Bonarius
  • Patent number: 8629629
    Abstract: An apparatus and method provides a driver circuit that provides for power factor correction (PFC) to a load, such as a solid-state lighting (SSL) device, such as, for example, a light emitting diode (LED) or an array or cluster of LEDs. A programmable reference is provided in the circuit to operate in a fixed frequency peak current mode control (FFPCMC) or in a fixed frequency average current mode control (FFACMC). A driver circuit is employed to operate the SSL device using power derived from a main power source which may be DC or AC. In a FFPCMC embodiment, a programmable power reference is programmed to be a fixed DC voltage. In a FFACMC embodiment, source input current to the circuit can be programmed to be proportional to the rectified AC voltage after a bridge rectifier.
    Type: Grant
    Filed: August 25, 2009
    Date of Patent: January 14, 2014
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Suresh Hariharan
  • Patent number: 8593072
    Abstract: A circuit arrangement for operating a high-pressure discharge lamp with an operating circuit for the high-pressure discharge lamp with an input for receiving a switch-on/switch-off signal for the high-pressure discharge lamp and at least one output for providing an operating signal to the high-pressure discharge lamp, wherein the operating circuit is designed to reduce the power of the operating signal provided at the at least one output once a switch-off signal has been received at its input, wherein the operating circuit furthermore designed to provide the operating signal as an AC signal above a predeterminable power threshold value and as a quasi DC signal below the predeterminable power threshold value.
    Type: Grant
    Filed: November 13, 2007
    Date of Patent: November 26, 2013
    Assignee: OSRAM Gesellschaft mit beschraenkter Haftung
    Inventors: Christian Breuer, Andreas Huber, Bernhard Reiter
  • Patent number: 8575849
    Abstract: A driver circuit, solid state light (SSL) source assembly including same, and a method of driving an SSL source are provided. The driver circuit includes a rectifier, an inverter, a transformer, a PFC circuit, and a frequency control. The rectifier receives an AC voltage and provides an unregulated DC voltage. The inverter includes two switches, and receives respective control signals to operate these, to generate a resonate AC signal from the unregulated DC voltage. The transformer includes a primary winding coupled to the inverter, a secondary winding to be coupled to an SSL source through an output stage, and a feedback winding. The PFC circuit controls the inverter in response to signals representative of the unregulated DC voltage and the inverter's current. The frequency control generates the control signals to control the inverter's switching frequency in response to signals representative of the output stage's current and the feedback winding's current.
    Type: Grant
    Filed: July 15, 2011
    Date of Patent: November 5, 2013
    Assignee: Osram Sylvania Inc.
    Inventor: Victor M. Simi
  • Patent number: 8552658
    Abstract: Apparatuses, methods, systems, and circuits for light-emitting diode (LED) control are disclosed. In one embodiment, an LED control circuit can include a first pin receiving an input voltage supply; a second pin receiving a primary signal from a primary winding of a transformer coupled to the LED; a third pin coupled to a ground supply; and logic configured to estimate an output current and/or output voltage at the LED coupled to a secondary winding of the transformer from the input voltage supply and the primary signal.
    Type: Grant
    Filed: August 25, 2009
    Date of Patent: October 8, 2013
    Assignee: Marvell World Trade Ltd.
    Inventors: Wanfeng Zhang, Jianqing Lin, Shaoan Dai
  • Patent number: 8547037
    Abstract: A liquid-cooled LED lighting device can be provided in which a temporal increase in the temperature of the tubing and the circulation pump when the LED light sources are turned off is prevented to ensure high reliability. The liquid-cooled LED lighting device can include an LED light source, a liquid cooling system including a heat receiving jacket and a radiator, an LED light source-driving power supply for supplying power to the LED light source, and a liquid cooling system-driving power supply for supplying power to the liquid cooling system. The LED lighting device can include a control unit, such as a timer circuit. The control unit can maintain supply of the power to the liquid cooling system for a predetermined period of time after supply of the power to the LED light source is stopped.
    Type: Grant
    Filed: November 25, 2009
    Date of Patent: October 1, 2013
    Assignee: Stanley Electric Co., Ltd.
    Inventors: Yasushi Yatsuda, Yasushi Hiramoto, Mitsuo Yamada, Teruo Koike
  • Patent number: 8547038
    Abstract: A high-pressure discharge lamp lighting device is used for projector devices that allow controlling the mean electric power at a desired value with a slow processing speed. A color wheel rotates and disperses the beam from lamp into each of the color components, such that the electric power supplied to the lamp is controlled at different levels for each segment of the color wheel and the power feeding device control part finds the mean electric power by sampling the electric power supplied.
    Type: Grant
    Filed: November 14, 2011
    Date of Patent: October 1, 2013
    Assignee: Ushio Denki Kabushiki Kaisha
    Inventor: Kosuke Saka
  • Patent number: 8531122
    Abstract: In various embodiments, a circuit arrangement may include a voltage-measuring device embodied to measure an output voltage, wherein the voltage-measuring device is embodied to provide at its output a signal which is correlated with the measured output voltage, wherein the voltage-measuring device is coupled to a control device for the purpose of transmitting said signal to the control device, and wherein the control device is embodied to vary an off-time as a function of the measured output voltage.
    Type: Grant
    Filed: September 17, 2008
    Date of Patent: September 10, 2013
    Assignee: OSRAM Gesellschaft mit beschraenkter Haftung
    Inventors: Alois Braun, Walter Limmer, Maximilian Schmidl
  • Publication number: 20130229127
    Abstract: The present invention relates to a method and system that provides independent control over lighting within a computer case. Each inverter module is provided with its own switch to facilitate independent control of illumination. Preferably, the switches are located in a bus that fits within a drive bay and the inverter is directly mounted onto the housing that contains the switch. In another embodiment, the inverter is integrated in a printed circuit board that is inserted into the card slots (e.g. ISA, VESA, PCI, and PCI-Express card slot) on the mother board of the computer. Therefore, the on and off of CCFL inverter can be controlled by software application through the ISA, VESA, PCI, or PCI-Express bus.
    Type: Application
    Filed: March 1, 2012
    Publication date: September 5, 2013
    Inventor: Michael T. Mueller
  • Patent number: 8519636
    Abstract: An alternating-current (AC) light-emitting diode (LED) apparatus is disclosed. A rectifier rectifies a power AC voltage to generate a rectified voltage, which is monitored by a controller. A number of LEDs are electrically coupled between the rectified voltage and a ground. A number of switches correspondingly control at least a portion of the LEDs respectively, wherein one terminal of each switch is electrically coupled to one electrode of the corresponding LED or LEDs. The switches are controlled by the controller according to the rectified voltage.
    Type: Grant
    Filed: January 6, 2011
    Date of Patent: August 27, 2013
    Assignee: GE Investment Co., Ltd.
    Inventor: Tsai Wen-Kuei
  • Patent number: 8502475
    Abstract: A discharge lamp ballast is provided with a feedback control operation to provide optimal lamp current flow during an electrode heating operation. A startup circuit coupled together with a discharge lamp between output terminals of a DC-AC power converter having a plurality of switches. The startup circuit generates a high voltage to ignite the lamp. A lamp current sensor detects an amplitude of an output current to the lamp. A control circuit controls the switches in accordance with each of a plurality of control operations including a startup operation to ignite the lamp using the high voltage generated by the startup circuit, an electrode heating operation wherein an operating frequency of the switches is controlled to set the amplitude of the detected output current to a predetermined target current amplitude, and a normal operation wherein the operating frequency is reduced to maintain stable lighting of the lamp.
    Type: Grant
    Filed: February 24, 2010
    Date of Patent: August 6, 2013
    Assignee: Panasonic Corporation
    Inventors: Nobutoshi Matsuzaki, Jun Kumagai, Satoru Nagata
  • Patent number: 8497637
    Abstract: A constant voltage dimmable LED (Light Emitting Diode) driver is disclosed that is compatible with all types of dimmers, including conventional phase cut (TRIAC) dimmers, and behaves like a conventional constant voltage driver which can be connected to any size of LED load that has a matching voltage rating. The driver produces a continuous train of pulses for driving the LED load and obtains an averaged measure of the voltage at the AC input for controlling the duty cycle of the continuous train of pulses. Therefore, when the averaged measure of the voltage at the AC input is reduced by a dimmer, the duty cycle reduces, resulting in a dimmed LED. The driver can be created by adding a few components to a conventional wide input range AC-DC converter without or with very little modifications.
    Type: Grant
    Filed: April 13, 2011
    Date of Patent: July 30, 2013
    Inventor: Gang Gary Liu
  • Patent number: 8493002
    Abstract: A driver (100; 200) for driving a dimmable load (L) is powered from phase-cut mains (U1) and determines the dimming state of the load on the basis of the phase of the cutting of the mains. The driver comprises: a load current generating device (130; 230) generating load current; a controllable auxiliary load (170; 270) connected to an input (131; 231) of the load current generating device; a control device (140; 240) controlling the auxiliary load. The control device has an input (141; 241) receiving a signal indicating the momentary voltage at the driver input. The load current generating device generates interrupted current pulses, so that the average output current corresponds to the dim command reflected by the phase cutting angle of the input mains. The control device switches the auxiliary load on during those time periods when the output current generated by the load current generating device is zero.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: July 23, 2013
    Assignee: Koninklijke Philips N.V.
    Inventors: Renatus Willem Clemens Van Der Veeken, Henricus Marius Joseph Maria Kahlman