Abstract: A lamp ignition system and a lamp ignition method are disclosed, where the lamp ignition system includes a converter, a transformer and a driving circuit. The converter converts an input voltage into an operating voltage for a gas discharge lamp. The transformer has a primary winding and a secondary winding, and the secondary winding is connected to the gas discharge lamp in series. The driving circuit is electrically connected to the primary winding for driving the transformer, so that the secondary winding of the transformer can output a high-frequency voltage to ignite the gas discharge lamp.

Abstract: A programmed start ballast circuit is presented having a mode control circuit to selectively switch an inverter output load to control operation for cathode preheating, step dimming and/or anti-arcing operation.

Abstract: According to one embodiment, a rectifying circuit includes a diode, a switching element, a capacitor and an auxiliary winding. The diode is connected between a first terminal and a second terminal while a direction directed from the second terminal to the first terminal is a forward direction. The switching element includes a first main electrode connected to the first terminal, a second main electrode connected to a cathode of the diode, and a gate electrode connected to an anode of the diode. The auxiliary winding is magnetically coupled to an inductor. The auxiliary winding is connected to the gate electrode through the capacitor, and is connected to the second main electrode of the switching element and the cathode of the diode.

Abstract: An LED drive circuit, which comprises a transformer, an MOS tube, a power regulating resistor, a direct current isolation circuit, a rectifying circuit, and a voltage control circuit; when the voltage of the control terminal of the voltage control circuit is higher than the threshold voltage of the MOS tube, the MOS tube is on, a current from an external power supply flows through the first winding of the transformer, the MOS tube and the power regulating resistor successively; when the voltage of the power regulating resistor is close to the voltage of the reference terminal of the voltage control circuit, the MOS tube is cut off, the second winding of the transformer charges the capacitor of the MOS tube via the direct current isolation circuit, the rectifying circuit is on, and the first winding of the transformer supplies power to the LED load via the rectifying circuit.

Abstract: An approach is provided for devices and methods for using high efficiency ballasted lamps with an electronic transformer, especially for the replacement of traditional halogen lamps from the existing fixtures. The method comprises acts of synchronizing a reference signal to a voltage corresponding to an AC voltage from an AC power source, and driving a load at a predetermined duty cycle. Therefore, the present disclosure is able to drive a load with a desired average output power lower than the minimum load requirement of the electronic transformer yet still allow the electronic transformer to work properly.

Abstract: A system includes a transformer. The transformer includes a first coil and a second coil. The first coil is configured to receive a first voltage based on an output of a switching circuit. The second coil is configured to generate a first current based on the first voltage to power a solid-state load. The system also includes a third coil. The third coil is configured to generate a second voltage based on the first voltage.

Abstract: In order to keep the advantage of PWM dimming control scheme and make the LED driver high reliability and the LED lamp long lifetime, it is required that the frequency of PWM dimming control scheme is related with or the same as the output frequency of existed dimmers; and the output PWM dimming pulse is covered by the output pulse from dimmers further. The present invention discloses a novel “LED dimming control” scheme to make that the frequency of PWM dimming control scheme is related with or the same as the output frequency of dimmers; and the output PWM dimming pulse is covered by the output pulse from the dimmers further. In this way, it can guarantee that as PWM dimming pulse comes, the output from the dimmer can offer enough power to the LED driver and the LED driver can output the required LED driving current without flicker.

Abstract: A light-emitting diode arrangement has a frame-shaped piezo transformer having at least one output-side connection, and having a light-emitting diode module that generates electromagnetic radiation, which module is disposed within the frame-shaped piezo transformer and electrically connects to the output-side connection of the piezo transformer by at least one output-side electrical conductor, wherein radiation emitted by the light-emitting diode module in the direction of the piezo transformer is reflected at the latter.

Abstract: Aspects of the disclosure provide a circuit that includes a detection circuit and a controller. The detection circuit is configured to detect a starting of a conduction in a power supply provided via an electronic transformer. The controller is configured to control a current regulating circuit to pull a current from the electronic transformer at a pre-determined level during a time duration following the starting of the conduction, and pull the current at a reduced level according to a pre-determined profile after the time duration.

Abstract: A switching power supply includes a switching element, a constant current element, a rectifying element, a first inductor, a second inductor, and a control circuit. If the switching element is on, the switching element supplies a power supply voltage to the first inductor and feeds an electric current. The constant current element turns off the switching element if the electric current of the switching element exceeds a predetermined upper limit. The rectifying element feeds the electric current of the first inductor if the switching element is turned off. The second inductor supplies the induced potential to a control terminal of the switching element. The control circuit supplies a pulse-like potential to a control terminal of the constant current element and outputs if an average of the potential is lower than a lower limit.

Abstract: A driver circuit for a dimmable solid state light source, and devices such as lamps and fixtures incorporating the same, and methods of driving such sources, are provided. A supply voltage circuit provides a supply voltage to a power factor controller circuit, such that the supply voltage is maintained within the high end of a nominal supply voltage operating range of the power factor controller circuit. The driver may also include an open circuit protection circuit for disabling the power factor controller circuit when an open circuit occurs in the load, and/or protection against electromagnetic interference (EMI).

Abstract: A method for driving the backlight unit of the liquid crystal display includes: comparing the strength of a soft start signal with a predetermined signal through a comparator circuit, and generating a first comparison signal or a second comparison signal according to the comparison result; outputting a first frequency from a frequency modulation circuit according to the first comparison signal; and increasing the rising rate of the output voltage of a boost converter according to the first frequency. Therefore, the rising rate of the output voltage is increased, thereby solving the screen-flickering problem.

Abstract: An illumination system includes a master power supply providing power to several illumination modules. The master power supply is constructed and arranged to generate high-frequency and low-voltage electrical power provided to a primary wire forming a current loop. Each illumination module includes an electromagnetic coupling element and several light sources. The electromagnetic coupling element includes a magnetic core arranged to receive the current loop in a removable arrangement, and a secondary wire wound around the magnetic core to enable inductive coupling. The secondary wire is connected to provide current to the light sources that may be arranged in the illumination module as a DC load or an AC load.

Abstract: An illuminating apparatus is disclosed. The illuminating apparatus includes a detecting unit, an illuminating unit, and a control unit. The illuminating unit includes multiple illuminating sets and a switching unit for adjusting a connection relationship among the illuminating sets. The detecting unit is for detecting an inputted power supply received by the illuminating unit while the control unit is coupled to the detecting unit and the switching unit. The control unit based on a detected inputted power supply controls the switching unit according to a predetermined setting parameter, so as to ensure a conducting voltage of the illuminating unit to vary according to a variation in the inputted power supply.

Abstract: A switching power supply includes a transformer, a resonant capacitor, a pair of switching elements, an inductor, and a rectifying element. The transformer includes a first winding, a second winding, and a third winding. The resonant capacitor is connected to both ends of the first winding. The switching elements are normally-on elements and alternately turned off according to a voltage induced in the third winding. Each of the switching elements includes a first main terminal, a second main terminal, and a control terminal. The inductor supplies a direct-current power supply voltage between the middle point of the first winding and the each first main terminal of the switching elements. The rectifying element rectify a voltage induced in the second winding.

Abstract: Embodiments of the present disclosure include an LED ballast circuit for dimming one or more LEDs using a phase controlled dimmer switch. The LED ballast circuit has a power conditioning unit which includes a substantially fixed duty cycle clock for outputting a clock cycle and a transformer configured to store energy and discharge a substantial portion of the stored energy once per clock cycle in order to power one or more LEDs.

Abstract: The invention discloses a driving circuit structure for driving light-emitting loads. The driving circuit structure may include a power supplying device, a signal processing device and an impedance balancing device and a dimming control unit. The power supplying device is used for supplying an alternating current power supply. The signal processing device is used for converting the alternating current power supply into a direct current power supply, so as to drive the light-emitting loads. The impedance balancing device is used for balancing an alternating current magnitude of the alternating current power supply, so as to stabilize a direct current magnitude of the direct current power supply for driving the light-emitting loads. The dimming control unit is capable of controlling output luminance of the light-emitting loads.

Abstract: A power-factor-corrected power supply adapted to supply power to one or more light emitting diodes (LEDs), comprises: a triac dimmer electrically connected between an alternating current source and a bridge rectifier; a damping circuit electrically connected between the alternating current source and the bridge rectifier; a bleeder circuit configured to conduct current between a supply terminal of the bridge rectifier and ground only when a triac in the triac dimmer is not conducting current; a fast startup circuit configured to conduct current between the supply terminal of the bridge rectifier and a voltage supply terminal of a power-factor-corrected controller when the triac dimmer is initially turned on until a supply voltage capacitor coupled to the voltage supply terminal of the power-factor-corrected controller has charged; a dimming slope control circuit configured to reduce a first voltage sensed at a current sensing terminal of the power-factor-corrected controller, such that a reduced amount of cur

Abstract: The LED driver includes a rectifier, a switching circuit and a feedback circuit. The rectifier connects an AC power source and outputting DC power. The switching circuit connects the DC power of the rectifier to switch the DC power with pulse width modulation (PWM) and has an output end for connecting a load and a feedback control end. The feedback circuit is connected between the output end and the feedback control end of the switching circuit for controlling a duty cycle of the switching circuit depending on an output current of the output end to keep the output current constant.

Abstract: A driving circuit and lighting equipment using the same are provided. The driving circuit includes a first power receiving terminal, a second power receiving terminal and a power conversion unit. The first power receiving terminal receives an alternating current (AC) input signal. The second power receiving terminal is electrically coupled to a predetermined potential. The power conversion unit is electrically coupled to the first and second power receiving terminals for transforming the AC input signal into corresponding two AC output signals of different phases, wherein the two AC output signals are with the same current.

Abstract: The invention provides a current balancing circuit, which includes a plurality of light-emitting diode assemblies; an AC power generator for providing currents required by the light-emitting diode assemblies; and a plurality of current-equaling elements connected to the AC power generator, each of which is connected to a common mode connecting two light-emitting diode assemblies for balancing currents of the light-emitting diode assemblies.

Abstract: Exit and egress lighting, emergency lighting or emergency light fixture, having internal supercapacitor power sources are recharged after a power outage using a staggered power up process. For example, once an emergency light fixture detects a power-on transition from power being unavailable on a power source to power being available from the power source, the fixture waits a predetermined time to recharge a supercapacitor based on a charge time delay value. The predetermined time may be selected to be unique for one or several emergency light fixtures so as to distribute a combined peak power demand of the fixtures. After the predetermined time has expired, the supercapacitor is electrically coupled to a power source to in order to recharge the supercapacitor.

Abstract: Power consumed by an LED driver may be reduced by drawing, from an electronic transformer or dimmer, an input current that is constant over a plurality of input voltages. Power derived from the constant input current is provided to the LED driver.

Abstract: An arc detection circuit that detects an occurrence of arcing between ballast and a lamp is provided. A transformer has a primary side connected between the ballast and the lamp to receive lamp current and conduct the lamp current from the ballast to the lamp during normal operation. A secondary side of the transformer produces a transformer voltage as a function of the lamp current received by the primary side. The produced transformer voltage is less than a threshold value during normal operation and greater than the threshold value during an occurrence of arcing between the ballast and the lamp. The arc detection circuit reduces the produced transformer voltage and provides it to the ballast so as to shut down the ballast operation.

Abstract: In a first aspect, an LLC resonant converter is provided for driving a plurality of output circuits from a DC input signal. The LLC resonant converter includes: (a) an inverter circuit for converting the DC input signal to a square-wave signal; (b) an inductor network coupled to the inverter circuit; and (c) a plurality of transformers, each transformer including a primary winding and a secondary winding. The primary windings of the transformers are coupled in series, and the series-coupled primary windings are coupled in parallel with the inductor network. The secondary winding of each transformer is coupled to and provides a current to a corresponding one of the output circuits. The secondary winding currents are substantially equal, and power is processed by a single transformer between the DC input signal and each output circuit. Numerous other aspects are also provided.

Abstract: An electrical appliance, particularly a television or a monitor, having a lighting device (8) having light emitting diodes (12). The light emitting diodes (LED) (12) are collected in LED strings (11) and controlled by a balancing network (17). The balancing network (17) has a circuit branch (19) for each string (11), the circuit branches (19) being connected in parallel to each other. Disposed in each circuit branch (19), is a bridge rectifier (20) to which the LED string (11) is connected. Moreover, each circuit branch has a balancing transformer (23), wherein all the secondary windings (26) of the balancing transformer (23) are connected in series in a closed conductor loop (27), by which the currents in all circuit branches are balanced.

Abstract: There is provided a coil component in which a plurality of coils may be easily connected to external connection terminals. The coil component includes: a bobbin including a winding part having a coil wound therearound and a terminal connection part having at least one external connection terminal connected thereto, the external connection terminal having a lead wire of the coil connected thereto; and at least one auxiliary terminal part coupled to the terminal connection part to allow for an increase in an amount of the external connection terminal.

Abstract: An operating device for operation of at least one illuminant, such as one or more LEDs, includes first and second converters and first and second logic circuits. The first converter is supplied directly or indirectly with mains voltage, with a first reference potential. The second converter is galvanically isolated from the first converter, with a second reference potential for supplying a load circuit with the illuminant. The first logic circuit is for controlling the first converter, and the second logic circuit is for controlling the second converter. The first logic circuit and the second logic circuit are connected to one another, with potential isolation, via an interface.

Abstract: Lighting devices and operating methods are presented in which voltage or current perturbations of an OLED caused by a user pressing the OLED are monitored while the OLED is providing general lighting, and one or more lighting control signals are generated based on the sensed perturbations.

Abstract: An apparatus is disclosed for supplying power to a luminous load. The apparatus includes a transformer having a primary winding, and a control circuit adapted to generate an alternating current through the primary winding to develop an alternating voltage. The alternating current is based on a first signal derived from the input voltage, a second signal derived from the current, and a third signal varying substantially in-phase with the input voltage. The first and second signals are used to regulate the power delivered to the load, and the third signal is used to improve the power factor. A load interface circuit is provided to generate an output voltage for the luminous load based on the alternating voltage from the transformer. An over-temperature sensor may be provided to cause a reduction in power to the load when the ambient temperature exceeds a threshold.

Abstract: A lighting system includes a transformer having a primary winding on a receiving path and a secondary winding on a delivering path. The receiving path receives electric energy regulated based on a dimming angle. The delivering path delivers the received electric energy. The lighting system includes a secondary switch, and a dimming controller. The secondary switch is switched on to couple a light source, such as an LED array, and the like, with the delivering path to emit light in response to the delivered electric energy and is switched off to decouple the light source from the delivering path. The dimming controller is configured to detect the dimming angle based on an electrical property of the delivering path. Then, the dimming controller switches on and switches off the secondary switch based on the dimming angle.

Abstract: A process for controlling a current supplied to a load includes, in at least one aspect, detecting input to control a current supplied to a load operated by a driving signal, and in response to detecting the input, modifying the driving signal to control the current supplied to the load, wherein modifying the driving signal comprises alternately applying a first duty cycle and a second duty cycle to the driving signal.

Abstract: A ultraviolet irradiation apparatus includes: an ultraviolet-irradiation water tank; a protection pipe provided in the ultraviolet-irradiation water tank; an ultraviolet lamp provided in the protection pipe to be lit up with high-frequency discharge at a frequency of 10 kHz to 10 MHz, inclusive; protection covers respectively provided on the two ends of the ultraviolet-irradiation water tank; an electronic ballast provided in one of the protection covers; and a feeder wire electrically connecting the ultraviolet lamp to the electronic ballast. Each of the ultraviolet-irradiation water tank and the protection covers is made of a conductive material with a specific conductivity and a relative magnetic permittivity whose product is equal to or larger than 1, and has a thickness at least three times as large as a skin depth at a frequency of a high-frequency current that flows through the ultraviolet lamp.

Abstract: When a voltage V detected by a voltage detecting section is lower than a first threshold value Vth1, an NPN transistor is turned on, a control terminal Ve is placed at a low level, and an overload protection circuit section halts the operation of a switching circuit section. When the voltage V detected by the voltage detecting section becomes higher than the first threshold value Vth1, the NPN transistor is turned off, the control terminal Ve is placed at a high level, and the overload protection circuit section resets the halt of the operation of the switching circuit section and makes the operation resumed.

Abstract: A lighting system for wirelessly providing power to a lighting assembly across a wall. The lighting system may be used, for example, for powering the lighting assembly positioned on an outside portion of the wall, such as on the outside of a boat hull. An example of the lighting system includes a power transmitter with a multi-frequency generator connected to a power source and a controller. The multi-frequency generator is configured to generate an oscillating signal at a predetermined frequency according to a control signal received from the controller. The power transmitter includes a transmitting coil connected to receive the oscillating signal. A receiving coil is positioned to form an inductive coupling with the transmitting coil. A plurality of conditioning units are connected to the receiving coil to receive the oscillating signal. The plurality of conditioning units are connected to provide power to a corresponding light or set of lights.

Abstract: A lighting system for illuminating a chamber in a building includes a lighting fixture suitable for being mounted onto a surface of the chamber, so that light emitted by at least one CCFL device mechanically supported by the fixture illuminates the chamber.

Abstract: A wireless power supply system for lighting includes: a power transmission unit including a power transmission coil; and a power reception unit including a power reception coil. The power transmission coil generates an AC magnetic field in response to a supplied AC power. The power reception coil receives an electric power from the power transmission unit through an electromagnetic induction due to the AC magnetic field generated by the power transmission coil. The power reception unit further includes a power circuit and a receive-side control section. The power circuit receives an output power from the power reception coil and to perform Buck-Boost operation so as to output a predetermined electric power to a lighting load. The receive-side control section controls the Buck-Boost operation of the power circuit. The power circuit is configured to be capable of boosting and stepping-down of the output power from said power reception coil.

Abstract: A power regulator 130 includes a power input line 181, a primary winding connected to the power input line 181 and wound on a core, a secondary winding, at least part of the secondary winding being in common with the primary winding, at least one tap 132, 133, and 134 connected to the primary winding at a predetermined position thereof to specify respective numbers of turns of the primary winding and the secondary winding, at least one switch S1, S2, and S3 having one end connected respectively to the at least one tap 132, 133, and 134 and another end connected to a common line 183 to change the respective numbers of turns of the primary winding and the secondary winding, and an output line 182 for outputting power that the secondary winding generates as the secondary winding is excited by the primary winding, wherein the respective numbers of turns of both the primary winding and the secondary winding are determined as one of the at least one switch S1, S2, and S3 is closed.

Abstract: An LED driver circuit and an isolated DC-DC converter therefor are presented, in which a primary side state estimator circuit is provided for inferred output current sensing for closed loop control of pulse width modulated flyback or buck converters. Specifically, the estimator circuit includes a capacitance having a first terminal coupled to a comparator input of a pulse width modulation controller, and a second terminal coupled to an error input of an error amplifier, and a switching device having a first power terminal coupled to the second terminal of the capacitance, a second power terminal coupled to the circuit ground, and a control input terminal coupled to a drive output of the pulse width modulation controller.

Abstract: An LED lighting apparatus includes a triac dimmer 3, a series circuit connected to the triac dimmer and including a primary winding P of a switching transformer T and a switching element Q1, the switching transformer having a plurality of windings, a controller 14 of the switching element, a rectifying-smoothing circuit of a voltage of a secondary winding S of the switching transformer, LEDs 1a to 1n connected to an output of the rectifying-smoothing circuit, a current detector 7 detecting a current of the, a voltage detector 11 configured to output a voltage detection signal of a voltage generated at one of the secondary winding when the first rectifying element is ON, the voltage at the secondary winding being proportional to the phase-controlled AC voltage, and an amplifier 13 amplifying a signal that is based on the current detection signal and voltage detection signal for the controller.

Abstract: A high-frequency lamp (10) for low-pressure and high-pressure applications, and a method for the operation thereof, that is particularly suitable for improving the characteristics with regard to efficiency, emission spectrum, cost, and long life, in that the use of an ignition unit is no longer necessary, even at very low high-frequency power, due to an impedance transformer (26) connected downstream of a power amplifier (20), because the application of as high a voltage as possible to an ionization chamber (16) is successfully achieved by the impedance transformation.

Abstract: An LED driving apparatus comprises a power supply unit that includes a transformer having a primary coil and a plurality of secondary coils and outputs alternating power from the plurality of secondary coils; a current balancing unit and a first rectification smoothing unit connected to a first secondary coil of the plurality of secondary coils; an LED load group that includes a plurality of LEDs connected in series and to which power smoothed from the first rectification smoothing unit is supplied; a power control unit that controls power to be supplied to the first and second LED loads, based on currents flowing in the first and second LED loads; and a direct current load that is connected to both ends of a second secondary coil of the plurality of secondary coils. The power supplying unit controls the alternating power, based on the power supplied to the direct current load.

Abstract: A multi-lamp driving system includes a filter circuit, a switch circuit, a pulse width modulation (PWM) controller, a protection circuit, transformers, and an abnormity detection circuit. Primary windings of the transformers are connected to the switch circuit in parallel, and high voltage terminals of secondary windings of the transformers are connected to lamps respectively. The abnormity detection circuit converts current signals flowing through the lamps into voltage signals, and retrieves highest and lowest voltage signals corresponding to highest and lowest current signal respectively. Then the abnormity detection circuit determines if a difference between the highest voltage signal and the lowest voltage signal exceeds a predetermined value, and generates a trigger signal if the difference between the highest and lowest voltage signals exceeds the predetermined value.

Abstract: A control circuit of a LED driver according to the present invention comprises an output circuit, an input circuit and an input-voltage detection circuit. The output circuit generates a switching signal to produce an output current for driving at least one LED in response to a feedback signal. The switching signal is coupled to switch a transformer. The input circuit samples an input signal for generating the feedback signal. The input signal is correlated to the output current of the LED driver. The input-voltage detection circuit generates an input-voltage signal in response to an input voltage of the LED driver. The input circuit will not sample the input signal when the input-voltage signal is lower than a threshold. The control circuit can eliminate the need of the input capacitor for improving the reliability of the LED driver.

Abstract: A light driver circuit device for synchronously driving a plurality of cold cathode fluorescent lamps (CCFLs) is provided. The light driver circuit device includes an inverter circuit board and a balance circuit board. The inverter circuit board has an inverter circuit coupled to a driving signal for outputting a driving voltage to drive the CCFLs synchronously. The balance circuit board and the inverter circuit board are installed separately, and the balance circuit board has a balance circuit coupled to a terminal of each CCFL and the inverter circuit. The CCFL driving architecture is designed to install the inverter circuit and the balance circuit individually, thus effectively reducing the space of the driving circuit and the total cost of the circuit design. Furthermore, the balance circuit board can balance the current in each CCFL effectively, and there is no limitation to where the balance circuit board can be disposed.

Abstract: An approach is provided for devices and methods for using high efficiency ballasted lamps with an electronic transformer, especially for the replacement of traditional halogen lamps from the existing fixtures. The method comprises acts of synchronizing a reference signal to a voltage corresponding to an AC voltage from an AC power source, and driving a load at a predetermined duty cycle. Therefore, the present disclosure is able to drive a load with a desired average output power lower than the minimum load requirement of the electronic transformer yet still allow the electronic transformer to work properly.

Abstract: A ballast circuit for a light emitting diode (LED) based lamp including power factor correction with protective isolation. The circuit includes a transformer with electrically isolated windings and a power factor correction circuit that receives no feedback from a secondary winding side of the transformer. An LED-based lamp assembly and a method of driving an LED-based light source are also provided.

Abstract: Disclosed are various embodiments of driver circuits that operate to excite devices for light emissions therefrom regardless of the impedance ratings thereof. The driver circuits are particularly suited to service both low impedance light emitting diode lighting devices and high impedance halogen lamps.

Abstract: There is provided a backlight unit driver capable of driving multi-channel lamps of a backlight unit, especially LED lamps, by supplying a driving power to the lamps using a single transformer and maintaining the current balance of the driving power supplied to each of the lamps.

Abstract: A method of driving a lamp that uses a DC to AC inverter that is connected to a primary winding of a transformer is disclosed. The inverter frequency is variable, and in one embodiment, may be controlled by a voltage controlled oscillator. Circuitry is included that monitors the phase relationship between a voltage across a secondary of the transformer and a current through the primary of the transformer. The circuitry monitors the phase relationship and adjusts the inverter frequency, such as by adjusting voltage controlled oscillator, so that the phase relationship is maintained at a predetermined relationship.