Abstract: A driving apparatus configured to drive a light emitting device includes a driving current source module operable to supply current to the light emitting device via a node during operation. A protection module coupled to the node and the driving current source module selectively injects current to the node during operation. The driving current source module is controlled based on a detection result of a voltage on the node.

Abstract: A bidirectional voltage differentiator circuit comprises start-up circuitry, sensing circuitry, and output circuitry coupled to logic circuitry. The start-up circuitry acts to start-up the sensing circuitry when the circuit is powered on, and accelerates the response of the sensing circuitry thereafter. The sensing circuitry senses variation in an input voltage applied to an input node. Responsive to the voltage variation sensed by the sensing circuitry, the output circuitry produces a state change at a first or second output node. The logic circuitry receives the states of the output nodes and produces a logic output signal to indicate the occurrence of the variation sensed in the input voltage. The voltage sensing circuit is operable to sense variation of the input voltage regardless of whether the voltage is rising or falling and without regard to the DC value of the input voltage.

Abstract: Described herein is an electronic device. The electronic device includes a unity gain buffer having an input coupled to an input node to receive an input voltage and an output coupled to an output node. A current sink circuit operates in a sleep mode in an absence of a sink current flowing into the output node, and operates in a sinking mode to sink the sink current from the output node to a reference supply node when the sink current flows into the output node.

Abstract: An adaptive dead time (ADT) control scheme for use with a switch mode power converter having a full bridge with synchronous rectifiers topology. A controller which implements the control scheme includes an input circuit arranged to receive a signal representative of the converter's output voltage, and an output circuit arranged to operate the converter's switching elements and synchronous rectifiers to produce a desired output voltage. The controller is further arranged such that the converter's “dead time” is adaptively varied in an inverse relationship to the magnitude of the load current. In a preferred embodiment, the signals used to operate the synchronous rectifiers are PWM signals, and the controller adaptively varies the dead time in a linear inverse relationship to the magnitude of the load current by modulating the rising and falling edges of the signals used to operate the synchronous rectifiers.

Abstract: A power converter can include an electrical isolation circuit between input and output nodes. An input signal monitor node can be provided, such as on a converter output side of the isolation circuit. In an example, a peak detection circuit can be coupled to the input signal monitor node. The output node of the power converter can be configured to supply an output power signal that is a function of an input signal at the input node. The power converter can include multiple, independently-switchable switches at one or more of the input and output sides of the isolation circuit. In an example, the power converter with the input signal monitor node can be configured as a bias supply to provide power, at the output node, to a controller circuit for a main stage power converter circuit.

Abstract: An amplifier circuit includes an input terminal and an output terminal. A current sinking transistor includes a first conduction terminal coupled to the output terminal and a second conduction terminal coupled to a reference supply node. A voltage sensing circuit has a first input coupled to the input terminal and a second input coupled to the output terminal. An output of the voltage sensing circuit is coupled to the control terminal of the current sinking transistor. The voltage sensing circuit functions to sense a rise in the voltage at the output terminal which exceeds the voltage at the input terminal, and respond thereto by activating the current sinking transistor.

Abstract: A driving apparatus configured to drive a light emitting device includes a driving current source module operable to supply current to the light emitting device via a node during operation. A protection module coupled to the node and the driving current source module selectively injects current to the node during operation. The driving current source module is controlled based on a detection result of a voltage on the node.

Abstract: This invention is related to efficient inorganic borophosphate phosphors which can applied in various technical applications such as fluorescent lamps, colored light or white light emitting diodes, and other devices where phosphors are used to convert especially near UV radiation into the visible light. Further, this invention is related to light sources comprising the efficient borophosphate phosphor. The inventive phosphor absorbs radiation in a first wavelength range of the electromagnetic spectrum and emits radiation in a second wavelength range of the electromagnetic spectrum. This phosphor is a borophosphate activated with divalent rare earth metal ions.

Abstract: The present invention relates to alkaline earth metal silicate luminophores having improved long-term stability and to a corresponding method for improving the long-term stability of alkaline earth metal silicate luminophores. The luminophore according to the invention is a luminophore comprising a base lattice according to the general chemical formula EAxSiyOz, where x, y, z>0. The component EA is formed by one or more alkaline earth metals. An activator, for example Eu2+ or Mn2+, is doped into the base lattice. The luminophore has the fundamental property to absorb radiation in a first wavelength range and emit radiation in a second wavelength range that is different from the first wavelength range. The luminophore is designed in the form of crystals. According to the invention, the surfaces of the crystals of the luminophore are chemically modified such that at least portions of the surfaces thereof are formed by a chemical compound of the general formula EauZ2.

Abstract: An adaptive dead time (ADT) control scheme for use with a switch mode power converter having a full bridge with synchronous rectifiers topology. A controller which implements the control scheme includes an input circuit arranged to receive a signal representative of the converter's output voltage, and an output circuit arranged to operate the converter's switching elements and synchronous rectifiers to produce a desired output voltage. The controller is further arranged such that the converter's “dead time” is adaptively varied in an inverse relationship to the magnitude of the load current. In a preferred embodiment, the signals used to operate the synchronous rectifiers are PWM signals, and the controller adaptively varies the dead time in a linear inverse relationship to the magnitude of the load current by modulating the rising and falling edges of the signals used to operate the synchronous rectifiers.

Abstract: An amplifier circuit includes an input terminal and an output terminal. A current sinking transistor includes a first conduction terminal coupled to the output terminal and a second conduction terminal coupled to a reference supply node. A voltage sensing circuit has a first input coupled to the input terminal and a second input coupled to the output terminal. An output of the voltage sensing circuit is coupled to the control terminal of the current sinking transistor. The voltage sensing circuit functions to sense a rise in the voltage at the output terminal which exceeds the voltage at the input terminal, and respond thereto by activating the current sinking transistor.

Abstract: The invention relates to a method of manufacturing a rare-earth doped alkaline-earth silicon nitride phosphor of a stoichiometric composition. Said method comprising the step of selecting one or more compounds each comprising at least one element of the group comprising the rare-earth elements (RE), the alkaline-earth elements (AE), silicon (Si) and nitrogen (N) and together comprising the necessary elements to form the rare-earth doped alkaline-earth silicon nitride phosphor (AE2Si5N8:RE). The method further comprises the step of bringing the compounds at an elevated temperature in reaction for forming the rare-earth doped alkaline-earth silicon nitride phosphor (AE2Si5N8:RE). In such a method normally a small amount of oxygen, whether intentionally or not-intentionally added, will be incorporated in the rare-earth doped alkaline-earth silicon nitride phosphor (AE2Si5N8:RE).

Abstract: This invention is related to efficient inorganic borophosphate phosphors which can applied in various technical applications such as fluorescent lamps, colored light or white light emitting diodes, and other devices where phosphors are used to convert especially near UV radiation into the visible light. Further, this invention is related to light sources comprising the efficient borophosphate phosphor. The inventive phosphor absorbs radiation in a first wavelength range of the electromagnetic spectrum and emits radiation in a second wavelength range of the electromagnetic spectrum. This phosphor is a borophosphate activated with divalent rare earth metal ions.

Abstract: This invention is related to efficient anorganic phosphors, which are based on an oxysulfide host lattice of the general formula ABOS:M. Furthermore, this invention is related to the use of these phosphors in various technical applications such as fluorescent lamps, colored light or white light emitting LEDs, scanning beam displays working with UV or purple laser as exciting source and other devices in order to convert especially UV or NUV radiation or short-wave visible light into an useful longer-wave visible radiation. This invention is also related to light sources and/or display applications that contain the inventive phosphor.

Abstract: An LED unit includes an LED having an optical axis and a lens mounted on the LED. The lens includes an incidence surface, an emission surface, and a light-reflecting face between the incidence surface and the emission surface. The light-reflecting face has a diameter gradually increasing from a bottom towards a top of the lens. The incidence surface includes a first incidence surface and a second incidence surface extending downwardly from a circumference of the first incidence surface and protruding inwardly towards the LED. Light emitted from the LED with a large angle is refracted by the second incidence surface into substantially parallel beams in one side of a cross-section of the lens through the optical axis of the LED, and the parallel beams are sequentially reflected by the light-reflecting face and refracted by the emission surface out of the lens in substantially parallel beams.

Abstract: An LED (light emitting diode) includes a light emitting chip and a lens above the chip. The lens includes a base and a convex curved circumferential surface extending upwardly from a periphery of the base toward a center of the lens. An acute angle formed between a light ray generated by the chip and projecting on a point of the convex curved circumferential surface and a main axis of the lens extending vertically from a center of the chip is smaller than that formed between the normal for the point of the convex curved circumferential surface and the main axis of the lens so that light generated by the chip is converged by the lens. A light-emission angle of the LED at 10% of a peak light intensity of the LED is ranged between 60-75 degrees from the main axis.

Abstract: An LED (light emitting diode) unit includes an LED and a lens mounted on the LED. The lens defines a passageway at a central portion thereof. The passageway runs through the lens. The lens includes a concave light emitting surface at a top thereof. Light output from the LED with a small light-emission angle travels directly through the passageway, without a loss of light intensity.

Abstract: The present invention relates to alkaline earth metal silicate luminophores having improved long-term stability and to a corresponding method for improving the long-term stability of alkaline earth metal silicate luminophores. The luminophore according to the invention is a luminophore comprising a base lattice according to the general chemical formula EAxSiyOz, where x, y, z>0. The component EA is formed by one or more alkaline earth metals. An activator, for example Eu2? or Mn2?, is doped into the base lattice. The luminophore has the fundamental property to absorb radiation in a first wavelength range and emit radiation in a second wavelength range that is different from the first wavelength range. The luminophore is designed in the form of crystals. According to the invention, the surfaces of the crystals of the luminophore are chemically modified such that at least portions of the surfaces thereof are formed by a chemical compound of the general formula EauZ2.

Abstract: A staggered frame aggregating method for multi-band time-division duplex mobile communication system. By relatively shifting the frame in each frequency band in turn, a new frame configuration is formed by aggregating and it is used for transmitting and receiving data, and it makes the frames in different bands stagger in time.

Abstract: An LED (light emitting diode) unit includes an LED and a lens mounted on the LED. The lens defines a passageway at a central portion thereof. The passageway runs through the lens. The lens includes a concave light emitting surface at a top thereof. Light output from the LED with a small light-emission angle travels directly through the passageway, without a loss of light intensity.