Abstract: A system drives one or a plurality of LEDs, regulating their brightness by controlling the LEDs' average current or voltage. The system includes a switching power converter and an integrated digital regulator with at least one of electrical, thermal, and optical feedbacks. The regulator is constructed as a hysteretic peak current mode controller for continuous mode of operation of the power converter. For a discontinuous mode of operation of the power converter, a pulse averaging sliding mode control is used. Average LED current is measured by integrating LED pulse current at off time and hysteretically adjusting on time of the power switch. An input battery is protected from discharging at abnormally low impedance of the output.

Abstract: Various embodiments of a coupled cavity traveling wave tube are disclosed herein. For example, some embodiments provide a coupled cavity traveling wave tube including a plurality of core segments arranged in spaced-apart fashion to form an electron beam tunnel, a first longitudinal member adjacent the plurality of core segments alternately extending toward and receding from successive core segments, and a second longitudinal member adjacent to the plurality of core segments alternately extending toward and receding from successive core segments. The first and second longitudinal members are offset to extend toward different core segments.

Abstract: A light emitting module driver circuit utilized for driving a light emitting module includes a voltage dividing module, a short circuit detection module, and a driving module. A method of performing short circuit protection in the light emitting module driver circuit includes disabling the driving module during a dimming off cycle of the light emitting module driver circuit, enabling the voltage dividing module during the dimming off cycle, dividing a voltage of the light emitting module to generate a divided voltage during the dimming off cycle, and generating a short circuit protection signal according to the divided voltage during the dimming off cycle.

Abstract: A transmitter includes a voltage conversion circuit converting supply voltage externally supplied into drive voltage and outputting the drive voltage; and an optical output unit which is supplied with the drive voltage and outputs an optical signal, wherein the voltage conversion circuit and the optical output unit are included in a same module.

Abstract: By monitoring the temperature of an LED and the temperature of a controller chip for the LED, a thermal foldback control is employed to gradually decrease the driving current of the LED before the LED or the controller chip is over heated, so as to prevent an over temperature protection from being triggered to shutdown the controller chip to cause the LED to undesirably flicker.

Abstract: A series connected light string using LEDs connected to an AC power source is disclosed. In order to make some or all of the lights color change, twinkle, and/or flash, controllers are provided in series with all or some of the LEDs. Because the supply source AC, but the active elements are essentially rectifiers, the circuit becomes a half wave DC circuit. Half wave DC will cause unpredictable behavior in DC circuit components. This will cause the controller to shut down during the zero voltage portion of the pulsating DC cycle. To prevent this a current supplying element is placed in parallel with the controller.

Abstract: An LED driving circuit includes a first and a second LED modules, a first and a second switching converters, an extreme voltage detecting and selecting circuit, a current balance circuit and a controller. The first switching converter transforms electric power of an input power supply into a first output voltage for lighting the first LED module. The second switching converter transforms electric power of the input power supply into a second output voltage for lighting the second LED module. The current balance circuit balances the currents flowing through the first and the second LED modules. The extreme voltage detecting and selecting circuit detects the first and the second LED modules and selects to output one of detecting results. The controller controls the transforming of the first switching converter and the second switching converter to light the first and the second LED modules in response to the outputted detecting result.

Abstract: The present invention is to provide an electronic ballast connected in parallel to two filaments of a fluorescent light tube, which comprises a controller for generating two output signals, two power switches being switched according to the output signals, a resonant circuit oscillating according to switching of the power switches and thereby causing a resonant capacitor thereof to generate a voltage, a voltage sensor connected in series to the resonant capacitor and connected in parallel between the two filaments so as to sense an AC voltage proportional to a voltage across the fluorescent light tube, and a regulator connected separately to the voltage sensor and controller so as to convert the AC voltage into a DC voltage and deliver the DC voltage to the controller. Upon determining that the DC voltage exceeds a preset voltage level, the controller generates an interruption control signal for immediately stopping operation of the controller.

Abstract: A magnetically shielded, efficient plasma generation configuration for a pulsed discharge extreme ultraviolet (EUV) light source comprises two opposed convex electrodes mounted with axes parallel to a static magnetic field. A limiter aperture disposed between the electrodes, in conjunction with the field lines, defines a hollow plasma cylinder connecting the electrodes. A high pulsed voltage and current compresses the plasma cylinder and its interior magnetic field onto the electrode surfaces to create a magnetic insulating layer at the same time as propelling the working gas from each side toward the space between the electrode tips. The plasma then collapses radially in a three-dimensional compression to form a dense plasma on the axis of the device with radiation of extreme ultraviolet light.

Abstract: An arc discharge detecting circuit includes; a voltage dividing part which divides a driving voltage provided to a light source, a detecting part which includes a loop-shaped wiring spaced apart from the voltage dividing part and which detects a current corresponding to an arc discharge flowing through the voltage dividing part using a coupling capacitance generated between the loop-shaped wiring of the detecting part and a wiring of the voltage dividing part, and an output part connected to the detecting part to output a detection voltage corresponding to the arc discharge. Accordingly, the arc discharge detecting circuit may improve a sensitivity of detecting an arc discharge as a current source type using the coupling capacitors, a design may be simplified, and manufacturing costs may be decreased.

Abstract: A load current balancing circuit that operates with a direct current (DC) power supply includes at least one transformer having a first inductive element adapted to couple in series with a first load and a second inductive element adapted to couple in series with a second load. The first load is parallel to the second load. The load balancing circuit further includes at least one switch adapted to operate at one or more switching frequencies associated with at least one driving signal. The switch is configured to periodically interrupt respective current flows through the first inductive element and second inductive element substantially simultaneously.

Abstract: A networked light bulb is disclosed comprising means for controlling a state of the networked light bulb, means for connecting to a network, means for allowing a user to select a color from a plurality of colors, the plurality of colors having at least one locking color and one or more non-locking colors, and means for generating a selected color code corresponding to the color selected by the user, each color of the plurality of colors having a corresponding color code. If the user selects the locking color, the networked light bulb disconnects from the network and turns the light bulb on. If the user selects a non-locking color, the networked light bulb submits the selected color code over the network for use by the network controller in configuring the device and changes the state of the networked light bulb in response to a command from the network. In some embodiments the networked light bulb also responds to requests for status information from the network independent of the color selected by the user.

Abstract: A driving circuit for light emitting elements comprises a rectifying unit, a first constant current unit, a first driving transistor, a first voltage control unit and at least one first light emitting element. The rectifying unit has a first terminal and a second terminal, is connected to an external power source that provides alternating current power that is sinusoidal and has alternating negative and positive segments, inverts the negative segments of the AC power to positive segments and forms a pulsating direct current voltage. The first constant current unit has a first end and a second end. The first driving transistor comprises a first gate, a first drain and a first source. The first voltage control unit comprises a first variable resistor and a first bias control element. The first light emitting element has a first end and a second end.

Abstract: A representative apparatus embodiment provides for controlling current supplied to solid state lighting, such as light emitting diodes. A representative apparatus comprises a memory adapted to store a plurality of current parameters, and a control circuit adapted to modulate an energizing cycle time period for providing a substantially constant DC average current to the solid state lighting in response to a selected current parameter from the plurality of current parameters. In a representative embodiment, the control circuit modulates a current provided to the solid state lighting in response to a predetermined minimum current level (IMIN) parameter and a predetermined peak current level (IP) parameter, such that the DC average current level (IO) is substantially proportional to one-half of a sum of a predetermined peak current level (IP) and a predetermined minimum current level I M ? ( I O ? I P + I MIN 2 ) .

Abstract: An LED package comprises a substrate, a constant current die, an LED die and an encapsulation body. The substrate has a plurality of internal conductive contacts and a plurality of external conductive contacts. The constant current die is electrically connected to the internal conductive contact, and comprises a constant current circuit and a protection circuit in parallel, wherein the constant current circuit allows a first current to flow through and the protection circuit allows a second current, in an opposite direction to the first current, to flow through. The LED die is electrically connected to the internal conductive contact. The encapsulation body encapsulates the constant current die, the LED die and the internal conductive contacts of the substrate. Having a small volume, the LED package can be applied to a compact lamp and prevents the LED from being damaged. An LED lamp comprising the LED package is also disclosed.

Abstract: In an illumination system (1) having a control unit (2) and at least one de-central lamp operating device (12, 22) for operating one or more associated lamps (LA), the lamp operating device (12, 22) can be operated in different operational modes. In accordance with the invention the central control unit (2) and the lamp operating device (12, 22) are so configured that the selection and setting of an operational mode for the lamp operating device (12, 22) can be carried out from or via the central control unit (2).

Abstract: A dual colored LED decoration lamp which includes a lamp string combined of multiple dual colored LED lights and a controller connected between the power supply and the lamp string. The lamp string includes lamp groups combined of multiple LED lights with two different colors and with their anodes and cathodes cross-linked. The multiple lamp groups are then connected in series, and each LED light in every lamp group is connected in same direction with the same colored LED light in the next lamp group. The controller controls the variation of the direction of current in aforementioned lamp strings. Thus, the lamp string is able to emit light with different colors by varying the current direction in the same lamp string through the usage of controller, and there is no need to set with multiple lamp strings.

Abstract: Disclosed is a lighting device.

Abstract: An EL display device capable of performing clear multi-gradation color display and electronic equipment provided with the EL display device are provided, wherein gradation display is performed according to a time-division driving method in which the luminescence and non-luminescence of an EL element (109) disposed in a pixel (104) are controlled by time, and the influence by the characteristic variability of a current controlling TFT (108) is prevented. When this method is used, a data signal side driving circuit (102) and a gate signal side driving circuit (103) are formed with TFTs that use a silicon film having a peculiar crystal structure and exhibit an extremely high operation speed.

Abstract: A self-oscillating switch circuit is configured for use in a switching DC-DC converter (switched mode power supply (SMPS)). The self-oscillating switch circuit comprises an input terminal (Tin1, Tin2) for receiving power from a power supply (51) and an output terminal (Tont1, Tont2) for supplying power to a load. The load may be a high-power LED, for example. The self-oscillating switch circuit further comprises a power switch semi-> conductor device (Q1) having a control terminal and a control semi-conductor device (Q2) coupled to the power switch semi-conductor device. The power switch semi-conductor device is configured for controlling a load current between the input terminal and the output terminal and the control semi-conductor device is configured for supplying a control signal to the control terminal of the power switch semi-conductor device for controlling switching of the power switch semi-conductor device.