A lighting device (100), comprising a light source (104) configured to be driven by electrical power, an energy-storage unit (106) configured to store electrical energy, to receive the electrical power from a power interface and to deliver the electrical power to the light source and to the power interface (108) allowing, in a connected state, an energy-transfer operation between the energy-storage unit (106) and an external second energy-storage unit (110) of an external electrically driven device (102) that can be connected to the power interface (108) and a control unit (116) configured to determine if the power interface (108) is in the connected state, to determine a current light-output state of the lighting device (100), and to control, in the connected state, the energy-transfer operation in an energy-transfer direction depending on the current light-output state of the lighting device (100).

A Light-Emitting Diode (LED) apparatus has a power source outputting a source DC power at a source DC voltage, a plurality of LEDs drivable at a driving DC voltage lower than the source DC voltage, and an electrical path connecting the power source to each LED for powering the LED by the power source. Each electrical path comprises a first portion connected to the power source at the source DC voltage and a second portion connected to the LED at the driving DC voltage, and the length of the first portion is longer than that of the second portion.

A Light-Emitting Diode (LED) apparatus has a power source outputting a source DC power at a source DC voltage, a plurality of LEDs drivable at a driving DC voltage lower than the source DC voltage, and an electrical path connecting the power source to each LED for powering the LED by the power source. Each electrical path comprises a first portion connected to the power source at the source DC voltage and a second portion connected to the LED at the driving DC voltage, and the length of the first portion is longer than that of the second portion.

A display device having a partially transparent substrate with a plurality of electrical consumers arranged in series having first and second contacts for applying a first and a second potential, and a third contact for receiving a control signal. A partially transparent electrically conductive layer electrically contacts the electrical consumers. A first and second connector for applying the first and the second potential to the conductive layer, and a third connector for applying the control signal. The conductive layer is attached to the transparent substrate with the three segments insulated from one another. A first and second segment are distanced from one another by a third segment. The first segment contacts the first connector and the first contact of one or more consumers, and the second segment contacts the second connector and the second contact of a consumers. The third segment contacts a third contact of an electrical consumer.

A compound of the general formula

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a process for the production of the compound and its use in electronic devices, especially electroluminescent devices. Improved efficiency, stability, manufacturability, or spectral characteristics of electroluminescent devices are provided when the compound of formula I is used as host material for phosphorescent emitters in electroluminescent devices.

A compound of the general formula

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a process for the production of the compound and its use in electronic devices, especially electroluminescent devices. Improved efficiency, stability, manufacturability, or spectral characteristics of electroluminescent devices are provided when the compound of formula I is used as host material for phosphorescent emitters in electroluminescent devices.

In one embodiment, a Light Emitting Diode (LED) driving device for driving a plurality of LEDs has a switching matrix utilizing a plurality of one of a turn off thyristors or turn off triacs coupled to the plurality of LEDs. A controller is coupled to the switching matrix responsive to a voltage of a rectified AC halfwave, wherein combinations of the plurality of LEDs are altered to ensure a maximum operating voltage of the plurality of LEDs is not exceeded. A current limiting device is coupled to the combinations of the plurality of LED to regulate current. In a second embodiment an offline charge pump utilizes a switching matrix to recombine capacitors in accordance with the voltage on the AC half wave and then in, accordance with a desired output voltage to feed a load, such that said recombinations occur at a frequency much higher than the frequency of the AC rectified half wave such that charge is pumped from the input at one voltage to the output at another voltage through the AC halfwave while, providing a constant output voltage to the load.

In one embodiment, a Light Emitting Diode (LED) driving device for driving a plurality of LEDs has a switching matrix utilizing a plurality of one of a turn off thyristors or turn off triacs coupled to the plurality of LEDs. A controller is coupled to the switching matrix responsive to a voltage of a rectified AC halfwave, wherein combinations of the plurality of LEDs are altered to ensure a maximum operating voltage of the plurality of LEDs is not exceeded. A current limiting device is coupled to the combinations of the plurality of LED to regulate current. In a second embodiment an offline charge pump utilizes a switching matrix to recombine capacitors in accordance with the voltage on the AC half wave and then in, accordance with a desired output voltage to feed a load, such that said recombinations occur at a frequency much higher than the frequency of the AC rectified half wave such that charge is pumped from the input at one voltage to the output at another voltage through the AC halfwave while, providing a constant output voltage to the load.

A radio frequency power system includes a master RF generator and an auxiliary RF generator, wherein each generator outputs a respective RF signal. The master RF generator also outputs a RF control signal to the auxiliary RF generator, and the RF signal output by the auxiliary RF generator varies in accordance with the RF control signal. The auxiliary RF generator receives sense signals indicative of an electrical characteristic of the respective RF signals output by the master RF generator and the auxiliary RF generator. The auxiliary RF generator determines a phase difference between the RF signals. The sensed electrical characteristics and the phase are used independently or cooperatively to control the phase and amplitude of the RF signal output by the auxiliary RF generator. The auxiliary generator includes an inductive clamp circuit that returns energy reflected energy back from a coupling network to a variable resistive load.

Systems and methods for light emitting diodes (LEDs) circuits are provided. Aspects include a set of light emitting diodes (LEDs) arranged in series between a first node and a second node, a power supply coupled to the first node, a first switching element arranged in series between the first node and a third node, wherein the first switching element is in parallel with the set of LEDs, a first charge pump coupled to the third node, a controller configured to operate the first switching element by providing a control voltage for switching the first switching element between an ON and an OFF, wherein the control voltage comprises a switching frequency, and wherein the first charge pump is charged by the power supply responsive to the switching element being in an ON state.