Abstract: A method of determining a drive signal provided to a light-emitting diode (LED). The method including sensing, via a first sensor, a first light intensity corresponding to a natural light in a room, sensing, via a second sensor, a second light intensity for a zone of the room, determining, via the controller, an expected light intensity, and determining, via the controller, whether the second light intensity exceeds the expected light intensity. The method further including, in response to determining that the second light intensity exceeds the expected light intensity, determining, via the controller, an artificial light intensity, determining, via the controller, the drive signal based on a desired light intensity for the zone of the room, the artificial light intensity, the first light intensity, and the second light intensity, and controlling, via the controller, the driver to provide the drive signal to the LED array.

Abstract: A method of determining a drive signal provided to a light-emitting diode (LED). The method includes in response to determining that a second light intensity exceeds the expected light intensity, determining, via the controller, an artificial light intensity based on a task-to-sensor ratio, determining, via the controller, a total natural light intensity based on the second light intensity and the artificial light intensity, determining, via the controller, a non-useful natural light intensity based on the total natural light intensity, the first light intensity, and the task-to-sensor ratio, determining, via the controller, the drive signal based on a desired light intensity for the zone, the total natural light intensity, the non-useful natural light intensity, and the artificial light intensity, and controlling, via the controller, the driver to provide the second drive signal to the LED array.

Abstract: A resonant tank circuit for a DC-to-DC converter includes a resonant inductor having a first terminal connected to a switching node of a half-bridge switching circuit. The resonant inductor has a second terminal connected to resonant tank circuit output node. A first capacitor has a first terminal connected to a voltage reference and has a second terminal connected to a capacitor branch node. A second capacitor has a first terminal connected to the capacitor branch node and has a second terminal connected to the resonant tank output node. A first diode has an anode connected to the voltage reference and has a cathode connected to the capacitor branch node. A second diode has an anode connected to the capacitor branch node and has a cathode connected to a voltage rail.

Abstract: A lighting system including a driver providing a first drive signal and a second drive signal; an LED array coupled to the driver and configured to receive the first second drive signals; a sensor positioned to sense light intensity for a zone; and an electronic controller. The electronic controller configured to control the driver to provide the first drive signal to the LED array; receive, from the sensor, a first light intensity; retrieve from the memory a task-to-sensor ratio for the sensor; retrieve from the memory a non-useful light intensity; determine an artificial light intensity based on first drive signal and the task-to-sensor ratio; determine the second drive signal based on a desired light intensity for the zone, the non-useful natural light intensity, and the artificial light intensity; and control the driver to provide the second drive signal to the LED array.

Abstract: Embodiments of the invention relate generally to lighting devices and, more particularly, to elongate lighting devices having components adapted for interconnection, as well as lighting systems including such lighting devices. In one embodiment, the invention provides a lighting device comprising: an elongate housing; at least one light-emitting device within the housing; and a first connection device at a first end of the elongate housing, the first connection device being electrically connected to the at least one light-emitting device.

Abstract: A system and method for controlled illumination in a bioanalysis or other system where excitation of fluorescent molecules is desirable. In an embodiment, an illumination system is described which can provide excitation light at a controlled intensity to provide quantitative results. In an embodiment, a solid state light engine is described which includes a plurality of color channels each providing light output suitable for exciting a fluorescent molecule, a light to frequency converter which receives a portion of the light output, a counter which maintains a count of a signal from the light to frequency converter, and a light intensity circuit, responsive to the counter, which adjusts the color channels to control the intensity of the light output.

Abstract: An electronic ballast is provided with a filament heating circuit having a Q factor clamped at a certain range of preheat frequency. An inverter circuit includes a pair of switches coupled between positive and negative terminals of a power supply, which oscillate at an operating frequency and generate an output voltage. A main resonant tank is coupled between an inverter output and the negative power supply terminal. A filament heating resonant tank includes a primary winding of a filament heating transformer coupled on a first end in series with the resonant capacitor, first and second capacitors coupled in series between the second end of the primary winding and the negative power supply terminal. A clamping circuit coupled to the second capacitor during a preheat mode of operation clamps an amplitude of the voltage across the primary winding to an amplitude of the input voltage from the power supply.

Abstract: The invention relates to a LED lighting system comprising a power supply circuit for supplying a LED current, equipped with input terminals (K1, K2) for connection to a supply voltage source and output terminals (K3, K4), modulation circuitry (MS, DC2), coupled between the output terminals, for alternately maintaining the voltage between the output terminals at a high level during a first time interval and a low level during a second time interval, a current sensor (R1, R2, S1) for sensing the current through the output terminals during the second time interval, and a driver circuit (DC1, DC2), coupled between the input terminals and the output terminals and coupled to the current sensor, for generating the LED current, out of a supply voltage supplied by the supply voltage source, wherein the LED current equals the current sensed by the current sensor multiplied by a predetermined constant multiplication factor and for supplying the LED current to the output terminals during each first time interval.

Abstract: A bi-level dimming control circuit is disclosed. The bi-level dimming control circuit is electrically coupled between two switches and a driver circuit that is compatible with 0 to 10 volt dimming signals. The bi-level dimming control circuit controls the output from the driver circuit based on the on and off positions of the switches. In repose to the on and off positions of the switches the driver circuit powers a light engine between a maximum light output mode, a zero light output mode and a reduced or dimmed light output mode. The bi-level control circuit is used to modulate LED light engines, fluorescent light engines and combinations thereof.

Abstract: An electrical ballast system having a toroidal current transformer having a core with a gap of predetermined dimensions, a primary winding, and a secondary winding. The primary winding is connected in series to a lamp load circuit and the secondary winding is connected to a transistor driver having an input. The improvement comprises the reduction of the effective area of the transformer core a sufficient amount to limit the output voltage amplitude of the secondary winding within a predetermined range compatible with the input of the transistor driver. The reduction of the effective area of the core is achieved with a cut or gap that covers up to 75% of the effective cross-sectional area. The resulting transformer will operate linearly for low load currents passing through the lamp and primary. For load currents above a predetermined magnitude, the core is saturated and additional magnetic flux lines pass through the gap, attenuated.

Abstract: A light emitting diode (LED) driving apparatus includes a DC-DC converter which provides a driving voltage to a plurality of LED arrays; a plurality of switching units, each of the switching units being connected in series to a corresponding LED array of the plurality of LED arrays and varying a size of a driving current to flow in the corresponding LED array of the plurality of LED arrays; and a control unit which, in order for each of the switching units to operate within a predetermined headroom voltage range, calculates a driving current of each of the plurality of LED arrays and a duty cycle of the switching units corresponding to each of the plurality of LED arrays, and controls the plurality of switching units based on the calculated driving current and the calculated duty cycle.

Abstract: A power supply circuit for operating high-efficiency lighting devices from a thyristor-controlled dimmer determines the dimming value, i.e., the dimmer duty factor by periodically probing the dimmer output. A minimum conductance is applied across the output of the dimmer during probing intervals that begin at the turn-on time of the dimmer and last until enough information has been gathered to correctly predict a next zero crossing of the AC line voltage that supplies the input of the dimmer. The dimming value is determined from the time interval between the predicted zero-crossing and a next turn-on time of the dimmer. The probing can be performed at intervals of an odd number of half-cycles of the AC line frequency so that a DC offset is not introduced within internal timing circuits of the dimmer. The AC line frequency can also be determined from a time interval between the predicted zero crossings.

Abstract: An LED driver is presented with a sensing circuit and attenuator circuits to provide three-way switched dimming as well as phase-cut dimming to control the output power driving an LED load allowing installation into conventional three-way switched lamp sockets or in sockets wired to a wall or table mounted phase-cutting dimmer control. When installed in a three way socket, the circuit senses the position of the three way switch and changes the lamp current accordingly. The lamp can also be dimmed by a table-top dimmer or a wall dimmer (in a three-way socket or in a conventional dual contact socket) by applying a phase-cut power input, with the driver circuit including circuitry to sense the average value of a phase-cut power line to adjust lamp current.

Abstract: An electrodeless plasma lamp is provided. The lamp includes a conductive enclosure including a dielectric material (e.g., air) and a bulb containing a fill to form a light emitting plasma. A radio frequency (RF) power source is coupled into to the enclosure. At least one conductive applicator applies power from the enclosure to the bulb and at least one limped inductive element is coupled between the RF feed and applicator. The lumped inductive element may be a helically wound coil. In an example embodiment, the lamp includes first and second lumped inductive elements. The first and second lumped inductive elements may extend from opposed end walls of the enclosure. The first lumped inductive element may be connected to a first conductive applicator located proximate a first end of the bulb and the second lumped inductive element may be connected to a second conductive applicator located proximate a second end of the bulb.

Abstract: An electronic ballast is provided with a filament heating circuit having a Q factor clamped at a certain range of preheat frequency. An inverter circuit includes a controller and a pair of switches coupled between positive and negative terminals of a power supply. The switches respond to control signals from the controller to oscillate at an operating frequency and generate an output voltage. An inverter tank is coupled to an inverter output terminal and includes a first capacitor, a primary winding of a filament heating transformer coupled on a first end in series with the first capacitor, a second capacitor coupled to the second end of the primary winding, and a clamping circuit coupled to the second capacitor. The clamping circuit during a preheat mode of operation clamps an amplitude of the voltage across the primary winding to an amplitude of the input voltage from the power supply.

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: A system and method for streetlight control is provided. A lamp sensor inside a reflector of the streetlight is utilized to detect the output of a lamp of the streetlight. During daytime periods when the lamp is OFF, the lamp sensor is utilized to act as a day/night sensor by detecting ambient light near the lamp. When the ambient light level falls below a sufficient level indicative that night is approaching the lamp is turned ON and the lamp sensor utilized to detect the lamp output of the streetlight.

Abstract: Fluorescent lamp ballasts and methods are disclosed in which a resonant impedance of a self-oscillating inverter is modified to control the inverter frequency to selectively preheat lamp cathodes using power from the inverter output during a preheating period after power is applied and to change the inverter frequency to a different range following ignition of the lamp.

Abstract: According to one embodiment, a lighting device includes a control circuit that includes a threshold for a case where a pair of the illumination lamps are connected in series between a positive output end and a negative output end of a power supply circuit, and a threshold for a case where one illumination lamp is connected between the positive output end and the negative output end of the power supply circuit. The control circuit determines the connected lamp number of the illumination lamps to a direct-current power supply device based on a voltage between the positive output end and the negative output end of the power supply circuit and a voltage between a non-potential connection end and the positive output end or the negative output end, and selects the threshold corresponding to the connected lamp number to control the direct-current power supply device.

Abstract: A low-temperature LED lighting and power supply device has a low power-consuming power supply control module and an LED lighting module electrically connected therewith. The LED lighting module is composed of at least one light source driver and an LED light source. The low power-consuming power supply control module at least has a surge suppression unit, a voltage-dividing-limiting unit, a current-limiting unit, and a steady voltage filtering unit. Accordingly, the present invention allows LED lighting equipment to be applied in a wider power supply range and operated under a low-temperature and low power-consuming state so as to meet economic and practical demands and environmental protection.

Abstract: An electronic ballast for operating at least one discharge lamp may include an input having a first and a second input connection for coupling to a DC supply voltage; a load circuit having an output; a constant-current transformer which includes a converter throttle, a converter diode and a converter switch, whereby the converter throttle is coupled serially between the first input connection and the load circuit; an activation circuit which is configured to activate the converter switch during operation with an HF signal; wherein at least one component across which a second voltage which is opposite in phase to the first voltage drops during operation is coupled between the internal and the external reference potential.

Abstract: An assembly includes an article, and a computer housing including left and right sidewalls cooperatively defining an accommodating space and an opening for communicating the accommodating space with an external environment, and a positioning member provided on one of the sidewalls. Each sidewall includes a slide rail. A package is mounted removably in the accommodating space via the opening, is connected slidably to the slide rails of the sidewalls, and is positioned within the accommodating space through the positioning member. The package includes two interconnected cover parts cooperatively defining a receiving space for receiving the article and a communicating hole for communicating the receiving space with the external environment, and a handgrip to mount removably the package in the accommodating space. Each cover part includes a stop member abutting against the article to prevent escape of the article from the receiving space via the communicating hole.

Abstract: An electronic ballast for operating at least two discharge lamps is provided, which may include a starting detection apparatus for detecting whether one of the discharge lamps has been started; wherein a drive circuit includes an input, which is coupled to a starting detection apparatus, wherein a threshold value entry apparatus is designed to enter a second threshold value for a setpoint value of a total current through at least two inductances, wherein the second threshold value has a smaller magnitude than a first threshold value; and wherein the drive circuit is designed to drive a first electronic switch and a second electronic switch taking into consideration the first threshold value as setpoint value prior to detection of the starting of a discharge lamp by the starting detection apparatus, and taking into consideration the second threshold value as setpoint value.

Abstract: The present invention provides a passive LC ballast and an associated method of manufacturing a passive LC ballast for use with any one of a plurality of high voltage discharge lamps. The passive LC ballast has an inductance and a capacitance selected in accordance with one of a set of one or more inductance-capacitance pairs. Each inductance-capacitance pair defines a respective inductance and a respective capacitance such that, when the inductance and the capacitance of the passive LC ballast is selected in accordance with any one of the inductance-capacitance pairs and the passive LC ballast is used with any one of the lamps, the lamp operates between respective minimum and maximum lamp powers of the lamp.

Abstract: A method of driving regulation for bipolar transistors in electronic ballast is provided. The method may include: sensing voltage at midpoint of half bridge of the transistors; producing a reference time signal according to a sync signal from a timer; producing actual time interval in this cycle by comparing rising edge of the voltage at midpoint of the half bridge of the transistors with rising edge of a driving signal for the transistors in upper bridge arm in each switching cycle; comparing the actual time interval with the reference time signal to determine pulse width of the driving signal; regulating, in which the driving signal in this switching cycle is prolonged relative to the driving signal in previous switching cycle if the actual time interval is larger than the reference time signal, while the driving signal in this switching cycle is shortened relative to the driving signal in previous switching cycle if the actual time interval is smaller than the reference time signal.

Abstract: The disclosure relates to an AC LED dimmer and dimming method thereof. The AC LED dimmer includes a rectifier receiving AC voltage from an AC voltage source and full-wave rectifying the AC voltage; a direct current (DC)/DC converter receiving the full-wave rectified voltage from the rectifier, generating a full-wave rectified stepped-up voltage, and generating a pulse enable signal; a pulse width modulation controller receiving the full-wave rectified stepped-up voltage and generating a pulse width modulation signal to dim an AC LED in response to the pulse enable signal; a switch driving the AC LED under control of the pulse width modulation signal, and an electromagnetic interference (EMI) filter to be connected between the AC voltage source and the switch to eliminate electromagnetic interference from the AC voltage source. Accordingly, the dimmer can perform an efficient and linear dimming function and suppress harmonics.

Abstract: In an optimum frequency detection sequence of a discharge lamp, the frequency control circuit performs a sweep operation in which, while the frequency control circuit monitors a synchronization degree signal, a frequency control signal is changed, so that frequency is changed, starting from either an upper or lower limit frequency of a periodic driving circuit, in a range that does not exceed the other frequency, wherein after completion of the sweep operation, the frequency control circuit determines a value of the frequency control signal corresponding to a resonance frequency of the resonant circuit, and inputs the value into a frequency driving circuit, wherein at least in a period of the sweep operation, an inverter receives power supply from a sweep time power supply circuit for supplying electric power with constant supply capability, which is limited to a range in which breakdown does not occur in the discharge lamp.

Abstract: An electronic ballast is provided for powering a discharge lamp and suppressing lamp flicker during startup transition. A power converter receives DC input power and converts it into an AC power output. A resonant circuit is coupled with the lamp and also between output terminals of the power converter. A controller controls the power converter with respect to particular modes of operation. The controller in a starting operation sets the output frequency of the power converter to a predetermined start frequency upon lamp startup to make the lamp begin discharging. The controller shifts from the starting operation to steady-state operation by setting the output frequency of the power converter at a predetermined steady-state frequency lower than the start frequency.

Abstract: A circuit for preheating filaments in lamps powered by an electronic ballast includes an inverter tank circuit and a preheat tank circuit. The preheat tank circuit has a preheat capacitor connected in parallel with a primary winding of a filament preheat transformer. A cut-back capacitor is connected between the preheat tank circuit and circuit ground. The filament preheat transformer has secondary windings coupled to the first and second lamp terminals to provide a filament preheat voltage. The inverter operates at a preheat frequency during a lamp preheat mode and at a steady-state frequency during a lamp steady-state mode, the steady-state frequency being lower than the preheat frequency. The preheat tank circuit has a natural resonant frequency that is approximately the same as the preheat frequency so that when the ballast is operating in the steady state mode, the filament voltage is substantially lower than when the ballast is operating in the preheat mode.

Abstract: A control means has an adjustment function in a microprocessor to adjust variations in an output to a discharge lamp due to variations in components by correcting a duty ratio of a PWM signal for varying an operating frequency of an inverter circuit so that a detected value of a second detection circuit falls within a target range. The microprocessor switches paths to transmit the PWM signal between a path passing through a feedback circuit and a path passing through a voltage follower circuit by switches a switch circuit to supply the signal through the path passing through the voltage follower circuit in adjusting output variations in the preheating mode and the starting mode.

Abstract: An electrical circuit and method for driving light emitting diodes with a constant current via a high efficiency DC-DC converter controlled by a digital controller through pulse width modulation (PWM).

Abstract: An electronic ballast for a discharge lamp includes a predictive circuit and a correction circuit in addition to a power conversion circuit including an inverter circuit and a resonant circuit, a drive circuit and a frequency control circuit. The inverter circuit applies load voltage across a load circuit including the lamp via the resonant circuit. The predictive circuit predicts a resonance frequency of the combination of the resonant circuit and the load circuit after ignition of the lamp. The resonance frequency is predicted based on an input signal representing the load voltage in the period of time from the start of sweep of the inverter circuit's operating frequency through a time point immediately after ignition of the lamp. The correction circuit changes the end frequency of the sweep to the resonance frequency.

Abstract: An exemplary power regulator apparatus provides power for illumination of a display object, such as a merchandise package or container, which has a light emitting apparatus comprising a secondary inductor and an illumination source. A support structure, such as a point of purchase display, typically contains or supports one or more power regulators and display objects. The power regulator comprises a controller and a primary inductor, and the controller is adapted to provide a voltage or current to the primary inductor to generate a primary inductor voltage. The controller may also comprise a plurality of switches and a memory adapted to store values for switching frequency or switch on-time durations or pulse widths. The illumination source emits visible light when the power regulator is in an on state and when the secondary inductor is within a predetermined distance of the primary inductor.

Abstract: A series circuit comprising a diode and a resistance is connected in parallel to a filament, and a series circuit comprising a diode and a resistance is connected in parallel to a filament. The filaments are preheated by a preheating current supplied from secondary windings of a preheating transformer, via preheating capacitors. Detection circuits detect DC voltage components of the preheating capacitors. Comparators compare the DC voltage components of the preheating capacitors with a reference voltage. The comparators cause a control circuit to protect the inverter circuit if an abnormality of the filaments is detected.

Abstract: A system and method includes a controller that is configured to coordinate (i) a low impedance path for a dimmer current, (ii) attaching a dimmer to a power converter system at the leading edge of a phase-cut, rectified input voltage, (iii), control of switch mode power conversion, and (iv) an inactive state to, for example, reduce the dimmer current while allowing a dimmer to function normally from cycle to cycle of an alternating current (AC) supply voltage. In at least one embodiment, the dimmer functions normally when the dimmer conducts at a correct phase angle indicated by a dimmer input setting and avoids prematurely resetting while conducting. In at least one embodiment, by coordinating functions (i), (ii), (iii), and (iv) the controller controls a power converter system that is compatible with a triac-based dimmer.

Abstract: A driving circuit includes a signal generator, a resonant circuit, a control circuit and an adjusting circuit. The signal generator is utilized for generating an alternating current (AC) signal having a fixed frequency. The resonant circuit is coupled to the signal generator, and is utilized for generating an oscillation signal to drive a backlight source according to the alternating current signal. The control circuit is utilized for providing a control signal. The adjusting circuit is coupled to the control circuit, the resonant circuit and the backlight source, and is utilized for providing an impedance according to the control signal to thereby adjust a current value of the backlight source.

Abstract: Provided is a light-emitting diode (LED) fluorescent lamp using as light sources a plurality of LEDs, which are eco-friendly and can contribute to power conservation. The LED fluorescent lamp includes an LED array including a plurality of LEDs connected in series; first through fourth connection pins; first through fourth capacitors connected to the first through fourth connection pins, respectively; a first diode having an anode connected to a second end of the first capacitor and a cathode connected to a first end of the LED array; a second diode having an anode connected to a second end of the LED array and a cathode connected to a second end of the second capacitor; a third diode having an anode connected to the second end of the LED array and a cathode connected to a second end of the third capacitor; and a fourth diode having an anode connected to a second end of the fourth capacitor and a cathode connected commonly to the first end of the LED array and the cathode of the first diode.

Abstract: A circuit arrangement for starting and operating at least one discharge lamp is provided.

Abstract: A circuit arrangement for operating at least one first and second lamp each provided with a first and second coil electrode includes a first and second terminal for the first coil electrode of the first lamp, a first and second terminal for the second coil electrode of the first lamp, a first and second terminal for the first coil electrode of the second lamp, a first and second terminal for the second coil electrode of the second lamp, at least one supply connection for supplying voltage to the respective first coil electrode of the at least one first and second lamp, and at least one preheating device for the respective first coil electrode of the at least one first and second lamp. The second terminal of the first coil electrode of the first lamp is coupled to the second terminal of the first coil electrode of the second lamp while the preheating device encompasses a first preheating inductor and a second preheating inductor.

Abstract: A pair of magnetically coupled inductors forms a current-compensated choke arrangement for reducing electromagnetic disturbances and for weakening the effects of glitch pulses during the ignition of a high-pressure discharge lamp. To further reduce these disturbances and glitch pulses, a resistor having a resistance value that is based on the impedance of the inductors within a given frequency range is arranged in series between a voltage source and the ignition device of the high-pressure discharge lamp. A filter capacitor across the input side of the current-compensated choke also further reduces these disturbances and glitch pulses.

Abstract: A drive circuit for a fluorescent display that can prevent generation of reactive power in a Zener diode used to generate a cutoff bias voltage. In one embodiment, the drive circuit operates as a single ended primary inductor converter (SEPIC) circuit and includes an input side closed circuit, an output side closed circuit, and a coupling capacitor connecting the two closed circuits. The input side closed circuit includes an input power source, a first inductor and a switching element. The output side closed circuit includes a second inductor, a diode and a second capacitor. A filament of the fluorescent display is connected to the second capacitor. One end of a Zener diode is connected to a negative potential side of the filament and the other end of the Zener diode is connected to an input power source.

Abstract: A method for igniting and operating a high intensity discharge (HID) lamp using an electronic ballast controlled by a ballast microcontroller. An ignition circuit including a parallel capacitive circuit is connected in parallel to the HID lamp. The ignition circuit being resonant at an ignition resonance frequency. An ignition voltage is provided to the HID lamp at the ignition resonance frequency, thereby initiating ignition of the HID lamp. Upon sensing the ignition, the HID lamp is powered at an operation frequency. Both the ignition resonance frequency and the operation frequency are in a high frequency range above fifty kilohertz. The ignition voltage preferably does not include a significant direct current offset The current flowing through the HID lamp is substantially continuous during the transition from providing ignition voltage during the ignition to powering the HID lamp at the operation frequency.

Abstract: The present invention relates to a power supply device for supplying power to a load, preferably a LED, comprising a first circuitry (12) with an inverter unit (24) adapted to provide an AC voltage, preferably a rectangular voltage, and a resonant circuit (30) with a capacitance (32) and an inductance (34), a second circuitry (14) with a rectifier unit (42), a switch (64) and said load (60), said switch being adapted to switch said load on and off, a controller unit (16) adapted to control said switch (64) as to adjust the power provided to said load (60) without any measurement signal from said primary circuitry (12), and a transformer (18) with a primary side (20) and a secondary side (22), said primary side being connected to said first circuitry (12) and said secondary side (22) being connected to said second circuitry (14), preferably said rectifier, so that said first and second circuitries are galvanically isolated.

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: A constant current source mirror tank dimmable ballast operates multiple high impedance lamps in a stable and balanced manner. The dimmable ballast has an inverter connected to two third-order resonant circuits. These third-order resonant circuits dominate the transfer function of the ballast circuits. Consequently, changes in the impedance of the lamp do not affect the current output to the lamps.

Abstract: The present invention discloses a piezoelectric cascade resonant lamp-ignition circuit, which uses the intrinsic capacitors of a piezoelectric transformer as piezoelectric capacitors. One lamp is cascaded to one set of the piezoelectric capacitors. Several sets of the piezoelectric capacitors and a resonant inductor are cascaded to form a resonant lamp-ignition circuit. The lamp-ignition circuit of the present invention has advantages of low temperature, small leakage current, high breakdown voltage and high lamp ignition efficiency. When applied to drive several lamps, the present invention uses a fixed frequency to attain a fixed inner impedance of the equivalent circuit of the piezoelectric capacitor. Thereby, the currents of the lamps are balanced to have an identical value.

Abstract: The invention relates to a ballast for a high-pressure discharge lamp, in particular for a motor vehicle headlight lamp or a projection lamp, which ballast is, according to the invention, in the form of a Class E converter.

Abstract: A piezoelectric type resonance high-voltage light-starting circuit, wherein, the intrinsic capacitance characteristic of a piezoelectric transformer is utilized as a piezoelectric capacitor, and said piezoelectric transformer connected to a light tube is connected in series with an independent inductor, thus forming a resonance type series-connected or parallel-connected light-starting circuit, hereby achieving the efficacy of small leakage current, low operating temperature, and high voltage endurance, as such raising the light-starting efficiency. Furthermore, in the application of said circuit mentioned above, output voltage is further amplified through a booster transformer, thus achieving its characteristics of high illuminance.

Abstract: An inductively powered gas discharge lamp assembly having a secondary circuit with starter circuitry that provides pre-heating when power is supplied to the secondary circuit at a pre-heat frequency and that provides normal operation when power is supplied to the secondary circuit at an operating frequency. In one embodiment, the starter circuitry includes a pre-heat capacitor connected between the lamp electrodes and an operating capacitor located between the secondary coil and the lamp. The pre-heat capacitor is selected so that the electrical flow path through the pre-heat capacitor has a lesser impedance than the electrical flow path through the gas of the lamp when power is applied to the secondary circuit at the pre-heat frequency, and so that the electrical flow path through the pre-heat capacitor has a greater impedance than the electrical flow path through the gas when power is applied the operating frequency.

Abstract: A ballast for operating a compact fluorescent lamp includes a power factor correction circuit and an energy storage capacitor coupled to the output thereof. The power factor correction circuit is configured to draw current from an AC power source during substantially more than half of the cycle of the input AC voltage waveform; i.e., when operated such that full power is supplied to the lamp. Energy transfer elements in the power factor correction circuit extract energy from the AC power source via an input rectifier, even when the peak voltage of the AC voltage waveform is substantially lower than the voltage of the energy storage capacitor, and transfer the energy to the energy storage capacitor a sufficient number of times during for each cycle of the input AC voltage waveform (e.g.