Abstract: A lamp driver circuit (400) comprises a feedback circuit for controlling stable operation of a discharge lamp (La), e.g. an inductively coupled discharge lamp such as a molecular radiation lamp, and for controlling a light output level of the discharge lamp (La). In particular, if the discharge lamp (La) is operated at a dimmed light output level, the light output is sensitive to changes in the lamp voltage (VLa), possibly resulting in flickering. In order to control stable lamp operation and prevent flickering, a high-sp feedback circuit is provided for controlling an operating frequency. In order to provide a relatively large dimming range for controlling the light output level, a low-speed feedback circuit is provided for controlling a DC supply voltage level (VDC).

Abstract: An electrical dimmer circuit comprising the electrical dimmer circuit for dimming the electrical power of a plurality of lighting means having at least one digital input channel, at which digital low-voltage input signals for specifying the light power of the various lighting means can be received, and having at least two output channels, on which output signals for dimming the electrical power of the respectively assigned lighting means can be output by pulse width modulation of a high alternating voltage.

Abstract: A power supply circuit for display unit according to one embodiment of the present invention includes a power supply circuit having outputs connected to a plurality of capacitance elements and supplying power to a plurality of drivers, and a controller switching connection of the power supply circuit and the capacitance elements depending on a use mode. The use mode includes a first use mode connecting one terminals of the capacitance elements to the power supply circuit or ground potential and a second use mode connecting one ends of the capacitance elements to the power supply circuit or floating one terminals of the capacitance elements.

Abstract: A driver circuit or controller flexibly drives either a half-bridge or a full-bridge switching network in a backlight inverter without modification, redundant circuitry or additional components. The driver circuit includes four outputs to provide four respective driving signals that establish a periodic timing sequence using a zero-voltage switching technique for semiconductor switches in the switching network.

Abstract: A high efficiency low power DC driver apparatus is presented for powering a light source, with a capacitive divider circuit receiving an AC input and providing a divided AC output, a rectifier provide a DC output below ten watts, output terminals coupleable to one or more light sources, and a linear regulator coupled in series with the light source to regulate a drive current flowing through the series circuit.

Abstract: A radio frequency plasma generator power supply, including: an interface that receives a request to determine an optimal control frequency; an output interface configured to be connected to a plasma generation resonator; a power supply module configured to apply a voltage at a set point frequency to the output interface, the voltage, depending on its frequency, selectively unable to allow generation of plasma of the resonator on receipt of a request during a phase optimizing power supply frequency of the generator and able to allow generation of plasma of the resonator during an operating phase; an interface that receives an electrical measurement of power supply of the resonator; a module that determines optimal control frequency, successively provides various set point frequencies to the power supply module on receipt of a request, and determines an optimal control frequency depending on electrical measurements received by the reception interface.

Abstract: An electronic ballast powers at least one fluorescent tube or lamp which has a power source; a DC power supply having an input connected to the power source; an oscillator connected to an output of said DC power supply so as to be driven therefrom; a driver means; and a protection means that deactivates the oscillator when the output reaches a predetermined abnormally high voltage. The protection means includes a transformer; a plurality of windings disposed on the transformer, a delegated winding disposed on the transformer. The protection means includes a sample point for sampling voltage. The protection means deactivates the delegated winding disposed on the transformer for the magnetizing the transformer and stopping oscillation when the sample point reaches a predetermined abnormally high voltage.

Abstract: A light source driving circuit includes a power supply circuit, a first dimming circuit, and a control circuit. The power supply circuit has a control terminal and an output terminal that is connected to a terminal of a first light-emitting element. The first dimming circuit has a first terminal connected to the other terminal of the first light-emitting element, a second terminal connected to a common potential, and a pulse width signal input terminal. The control circuit is connected between the pulse width input terminal of the first dimming circuit and the control terminal of the power supply circuit. The first dimming circuit determines an ON/OFF state according to a logic state of the pulse width signal. The power supply circuit determines whether or not to output the voltage. The control circuit delays the power supply circuit, turns off the power supply circuit, and delays the first dimming circuit.

Abstract: A method, apparatus, and system for compensating for lamp lumen depreciation and providing selective discretionary lamp power adjustment, e.g., for lamp dimming. The method includes operating the lamp under rated wattage for a period towards the first part of operating life of the lamp. Operating wattage is increased at one or more later times. Energy savings are realized. The increases also restore at least some light lost by lamp lumen depreciation. The apparatus uses a timer to track operating time of the lamp. A few wattage changes made at spaced apart times can be made in a number of ways, including changing capacitance to the lamp, or using different taps on the lamp ballast. A component allows selective discretionary adjustment of electrical power or some other controlling factor to adjust light output (e.g. dim) the lamp.

Abstract: The present invention includes a Zener diode connected between a helix electrode and an anode electrode, a transistor that closes or opens a circuit between a cathode and an anode of the Zener diode, a photocoupler for turning ON/OFF the transistor through a phototransistor, a first switch for supplying or cutting off a DC voltage for the photodiode of the photocoupler, a capacitor to which the DC voltage that is to be supplied to the photodiode is applied and a control unit that turns ON the first switch beforehand to apply a DC voltage to the photocoupler and the capacitor and that turns OFF the first switch simultaneously with an application of a helix voltage.

Abstract: An apparatus method and system are provided for power conversion, to supply power to a nonlinear load such as a plurality of light emitting diodes. An exemplary apparatus comprises a first power converter stage, a second power converter stage, a plurality of sensors such as first and second sensors, and a controller. The first power converter stage includes a power switch and a first inductor having a first inductance. The first and second sensors are both coupled to a common reference node, with the first sensor adapted to sense a first parameter of the first power converter stage, and the second sensor adapted to sense the output current level. The second power converter stage includes a second inductor having a second inductance, and is couplable to provide an output current to the nonlinear load such as LEDs.

Abstract: A two-dimensional circuit for a traveling-wave tube for millimeter and sub-millimeter electromagnetic waves synchronously interacts with an electron beam in a vacuum electronic microwave amplifier or oscillator. The circuit is a solid body having a length along the tube axis. The solid body has an electrically conductive top section and an electrically conductive bottom section. The top section is configured with a plurality of vertical vanes having a width and height and configured parallel to each other. The bottom section is similarly configured such that when the circuit is viewed in cross section along the length, the vanes on the bottom section are staggered with respect to the vanes on the top section. The top section and the bottom section are separated from each other to define a tunnel through the solid body along the length.

Abstract: A first voltage comparator makes a comparison between a first detection voltage that occurs at one terminal of a first resistor and a predetermined first threshold voltage. A second voltage comparator compares a second detection voltage that occurs at one terminal of a second resistor with a predetermined second threshold voltage. A logic unit generates a switching signal, the level of which is switched according to the output signals of the first voltage comparator and the second voltage comparator, and outputs the switching signal thus generated to the gate of a switching transistor. After a predetermined period of time elapses after the switching signal is switched to the level which turns off the switching transistor, an automatic restart circuit forcibly switches the switching signal to a level which switches the switching transistor to the ON state.

Abstract: A current-regulated light emitting device for vehicle use includes a light emitting unit and a current limiting unit. The current limiting unit includes first and second switches and first and second bias units. The first switch is for making and breaking an electrical circuit between the light emitting unit and an electric power source. The first bias unit is for causing the first switch to conduct so as to activate the light emitting unit when the first bias unit receives a drive voltage from the electric power source. The second bias unit is for causing the second switch to conduct when amount of current flowing through the first switch exceeds a predetermined threshold, thereby turning off the first switch to interrupt current flow through the light emitting unit.

Abstract: Apparatus and methods for the thermal management of one or more light emitting diode (LED) modules disposed within a channel sign are disclosed. The apparatus, in various aspects, detects the ambient temperature generally proximate the LED module and regulates the current flowed onto the LED's within the LED module based upon the ambient temperature. Methods for thermal management of the one or more LED modules disposed within a channel sign are disclosed herein.

Abstract: A dielectric waveguide integrated plasma lamp (DWIPL) with a body comprising at least one dielectric material having a dielectric constant greater than approximately 2, and having a shape and dimensions such that the body resonates in at least one resonant mode when microwave energy of an appropriate frequency is coupled into the body. A dielectric bulb within a lamp chamber in the body contains a fill which when receiving energy from the resonating body forms a light-emitting plasma. The bulb is transparent to visible light and infrared radiation emitted by the plasma. Radiative energy lost from the plasma is recycled by reflecting the radiation from thin-film, multi-layer coatings on bulb exterior surfaces and/or lamp chamber surfaces back into the bulb.

Abstract: A discharge lamp lighting apparatus includes a DC/DC converter for converting an input direct voltage to a direct voltage of a different voltage value than the input direct voltage by switching and then outputting the converted direct voltage; a discharge lamp driver for converting the output direct voltage, which is supplied from the DC/DC converter, to a voltage suitable for driving a discharge lamp; a pulse width controller for generating a pulse width controlled switching control signal based on a reference pulse and then supplying the switching control signal to the DC/DC converter; and a microprocessor for controlling the apparatus as a whole and supplying to the pulse width controller a pulse width control signal and the reference pulse in synchronism with the pulse width control signal.

Abstract: A ring balancer comprising a plurality of balancing transformers facilitates current sharing in a multi-lamp backlight system. The balancing transformers have respective primary windings separately coupled in series with designated lamps and have respective secondary windings coupled together in a closed loop. The secondary windings conduct a common current and the respective primary windings conduct proportional currents to balance currents among the lamps. The ring balancer facilitates automatic lamp striking and the lamps can be advantageously driven by a common voltage source.

Abstract: A method for controlling average current. The method enables control of average current independent of instantaneous current. The average current is controlled by changing the number of unit pulses provided during a time interval. The unit pulses are used to switch the delivery of current to the load.

Abstract: Described herein is a modulator circuit for generating discrete energy pulses in a device. The circuit includes a high voltage power source intermittently coupled to a saturable first inductor, a second inductor and a capacitor coupled in parallel between the high voltage power source and the saturable first inductor and second inductor. When the first inductor is unsaturated, its inductance is high and it isolates the capacitor from the second inductor. When the first inductor saturates, the inductance collapses and the capacitor discharges a high energy pulse into the second coil. By controlling the time to saturation, the timing of the pulses is controlled. The modulator circuit is effective to control pulses applied to a circular induction accelerator, such as a Betatron.