Abstract: The present invention relates to an LED retrofit lamp (700) adapted for operation with an alternating current. The LED lamp comprises an LED unit (740), a mains current line, first and second switching devices (710, 720) (e.g., first and second relays), and a control unit (730). The control unit (730) detects an ignition voltage on the mains current line. In response to detecting the ignition voltage on the mains current line, the control unit (730) sets the first and second switching devices (710, 720) to a conducting state such that the LED unit (740) is connected to power. By using the first and second switching devices (710, 720), safety of the LED lamp (700) is improved, in particular when installing the lamp (700) into a fixture designed for fluorescent lamps.

Abstract: An average power consumption of receiving units (3,5,7) for controlling apparatuses (4,6,8) in response to operation control signals from transmitting units (2) may be reduced by introducing devices (1,21) for controlling the power consumption of the receiving units (3,5,7) in response to detections of states of the apparatuses (4,6,8). The devices (1) may comprise controllers (30) for controlling the power consumption in a wireless, non-wireless, physical and/or logical manner. The devices (1) may comprise monitors (33) for monitoring power consumption, currents and/or voltages at the receiving units (3,5,7) and/or the apparatuses (4,6,8).

Abstract: The present invention relates to a harmonic compensation circuit for compensating at least the third harmonic in the input current (Imains) drawn by an LED light source (1) from a mains voltage supply (2), comprising: a signal input (21, 22) for receiving a first input signal proportional to the input voltage (Vin) of said LED light source (1) and a second input signal (Vsh) proportional to the LED current (ILED) of said LED light source (1), a signal output (25) for outputting a compensation current (Icomp), a processing unit (24a, 24b) for comparing said second input signal (Vsh) to a reference signal (VRb, VR7) and for generating said compensation current (Icomp) based on said comparison, the sum of said compensation current (Icomp) and said LED current (ILED) being proportional to the input voltage (Vin) of said LED light source (1) and said compensation current (Icomp) being provided for minimizing at least the third harmonic in the input current (Imains) drawn by said LED light source (1) from said main

Abstract: An illumination device (1) comprises: input terminals (2) for coupling to AC mains; a LED string (10) connected in series with the input terminals; a rectifier (30), having input terminals connected in series with the LED string; a controllable voltage source (40), having input terminals coupled to the rectifier output terminals; a series arrangement of at least one auxiliary LED (51) and a second ballast resistor (52) connected to the output terminals of the controllable voltage source. The voltage source comprises: a series arrangement of an adjustable first resistor (46) and a second resistor (47) connected in parallel to the input terminals; a tuneable Zener diode (49) connected in parallel to the output terminals, having a control input terminal (48) connected to the node between the two resistors; wherein positive output terminal is connected to positive input terminal and negative output terminal is connected to negative input terminal.

Abstract: A Wireless power transmission system comprises a base unit (1) with multiple magnetic field generator circuits and a device (10), separable from said base unit (1) having a receiving inductor, adapted to receive power inductively when said device (10) is in proximity to one of said generator circuits, wherein said base unit (1) comprises a controller (3), configured to determine a transmission circuit (2?) from said generator circuits when said receiving inductor is in proximity to said transmission circuit (2?), whereupon said transmission circuit (2?) is operated to generate a first magnetic field (8), having a first phase, to induce a current in said receiving inductor and at least one of the remaining generator circuits is operated as a compensation circuit (2?, 52, 82) to generate a second magnetic field (21), having an opposite phase to said first phase.

Abstract: Driving a lighting device by a driving circuit for providing driving power for driving a lighting device, and by a decoupling unit for electrically decoupling the driving circuit from a lighting circuit. The driving power is transferred at least partially from the driving circuit to the lighting circuit, and the lighting device is arranged within the lighting circuit such that its anode is at ground potential of the driving circuit.

Abstract: An illumination device (1) comprises: mains input terminals (2, 3); a power source (30), having input terminals (31, 32) coupled to the mains input terminals and having three output terminals (33, 35, 34), one of said output terminals being a common output terminal (35). A first output (36) is defined by a first output terminal and said common output terminal; a second output (37) is defined by a second output terminal and said common output terminal. A first LED string (110) is connected to the first power source output in series with a first resistor (120). A second LED string (210) is connected to the second power source output in series with a second resistor (220). The power source is controllable to vary the voltage at the common output terminal within the range from the voltage at the first output terminal to the voltage at the second output terminal.

Abstract: In light emitting diode circuits (1) comprising serially coupled first and second circuits (11, 12) with first and second light emitting diodes, third circuits (13) are coupled in parallel with the second circuits (12) for controlling the first light emitting diodes in the first circuits (11) and/or third light emitting diodes in fourth circuits (14). This allows more options, more optimizations, more flexibility and/or more efficiency. The light emitting diode circuit (1) receives a supply voltage from a source (2, 3) for feeding the light emitting diode circuit (1). The third circuit (13) receives a feeding voltage from the second circuit (12) for feeding the third circuit (13). The feeding voltage may be a voltage present across the second circuit (12). The third circuit (13) may further control the second light emitting diodes in the second circuit (12).

Abstract: An input stage (10) of an apparatus (1) for driving a light-emitting diode (40-42) receives a signal from a power supply (30-32), and an output stage (20) supplies a current to the light-emitting diode (40-42). The peak value divided by the average value of the current forms a ratio. The driving efficiency is improved by providing the input stage (10) with an arrangement (11) for reducing this ratio by manipulation of the signal, without the necessity of using any smoothing capacitors/inductors. The manipulation may comprise an addition of a frequency component to the signal or an adaptation of an amplitude of a frequency component of the signal. This frequency component may be a third and/or fifth and/or seventh harmonic frequency component of a fundamental frequency component of the signal. The arrangement (11) may comprise a resonant tank which may need to be tuned to the frequency component of the signal.

Abstract: The invention relates to a method and a device for driving an LED string of a first LED segment (11) and at least one further LED segment (12, 13, 14) connected in series. Each LED segment has at least one light emitting diode, LED. The LED string is powered by a rectified AC mains voltage. The first LED segment (11) is powered when the rectified AC mains voltage is above a first voltage level, and the first LED segment and the further LED segment are powered when the rectified AC mains voltage is above a second voltage level higher than the first voltage level. The first LED segment emits light having a first color temperature, and the further LED segment emits light having a second color temperature higher than the first color temperature. The light emitted by the first LED segment and the light emitted by the further LED segment are superimposed. The color temperature change of the light emitted by the LED string, when dimmed, resembles the color temperature change of an incandescent lamp.

Abstract: A light generating device (20) comprises: —a rectifier (23) rectifying an AC input voltage and providing a rectified AC output voltage (Vin); —a controllable current source (40); —a switch matrix (30) comprising a plurality of controllable switches (S1-SN); —a plurality of n LEDs (D1, D2, . . . Dn) connected to output terminals of the switch matrix (30); —a controller (50) controlling said switches and controlling the current generated by the current source dependent on the momentary value of the rectified voltage (Vin). The controller is capable of operating in at least three different control states. In a first control state all LEDs are connected in parallel. In a second control state all LEDs are connected in series. In a third control state at least two of said LEDs are connected in parallel while also at least two of said LEDs are connected in series.

Abstract: A light generating device (20) comprises: —an input for receiving a DC input voltage (Vin) of varying magnitude; —a controllable current source (40); —a switch matrix (30) comprising a plurality of controllable switches (S1-SN); —a plurality of n LEDs (D1, D2, . . . Dn) connected to output terminals of the switch matrix (30); —a controller (50) controlling said switches and controlling the current generated by the current source dependent on the momentary value of the DC input voltage (Vin). The controller is capable of operating in at least three different control states. In a first control state all LEDs are connected in parallel. In a second control state all LEDs are connected in series. In a third control state at least two of said LEDs are connected in parallel while also at least two of said LEDs are connected in series.

Abstract: The invention relates to an illuminated tiling system (100) which comprises back panels (10) with at least one electrically conductive layer (12, 13), plugs (20) with projections (21, 23) that electrically contact the conductive layer(s) (12, 13), and light-tiles (30) with (O)LEDs that can be fixed to the plugs. For an easy tiling, dummy-tiles can first be tiled together with conventional tiles (2) and later be replaced with the light-tiles (30).

Abstract: A method for manufacturing a flooring product with integrated circuitry, comprising the steps of providing a plurality of pieces (6), stacking said pieces on top of each other, displaced in relation to each other to form an offset stack (10), and compressing said offset stack to form said flooring product. The method further comprises arranging flexible circuitry (7) on an upper surface of at least one piece, so that, when said pieces are stacked, a first portion (7a) of flexible circuitry on the at least one piece is exposed, said first portion (7a) including circuitry for interacting with the environment. By arranging the circuitry in the flooring during such a manufacturing process, a flooring product is achieved where only a portion of the circuitry is exposed, and another portion is embedded in the flooring.

Abstract: The present invention relates to a low cost LED driver module comprising a switched-mode power supply (smps) having down-converting characteristics (11) which is controlled by a comparator (31). The comparator is hysteresis configured, which reduces ripple and transients in the LED current, and the module can be accomplished with inexpensive standard components.

Abstract: An illumination device (1) comprises: mains input terminals (2, 3); a power source (30), having input terminals (31, 32) coupled to the mains input terminals and having three output terminals (33, 35, 34), one of said output terminals being a common output terminal (35). A first output (36) is defined by a first output terminal and said common output terminal; a second output (37) is defined by a second output terminal and said common output terminal. A first LED string (110) is connected to the first power source output in series with a first resistor (120). A second LED string (210) is connected to the second power source output in series with a second resistor (220). The power source is controllable to vary the voltage at the common output terminal within the range from the voltage at the first output terminal to the voltage at the second output terminal.

Abstract: In light emitting diode circuits (1) comprising serially coupled first and second circuits (11, 12) with first and second light emitting diodes, third circuits (13) are coupled in parallel with the second circuits (12) for controlling the first light emitting diodes in the first circuits (11) and/or third light emitting diodes in fourth circuits (14). This allows more options, more optimizations, more flexibility and/or more efficiency. The light emitting diode circuit (1) receives a supply voltage from a source (2, 3) for feeding the light emitting diode circuit (1). The third circuit (13) receives a feeding voltage from the second circuit (12) for feeding the third circuit (13). The feeding voltage may be a voltage present across the second circuit (12). The third circuit (13) may further control the second light emitting diodes in the second circuit (12).

Abstract: An illumination device (1) comprises: input terminals (2) for coupling to AC mains; a LED string (10) connected in series with the input terminals; a rectifier (30), having input terminals connected in series with the LED string; a controllable voltage source (40), having input terminals coupled to the rectifier output terminals; a series arrangement of at least one auxiliary LED (51) and a second ballast resistor (52) connected to the output terminals of the controllable voltage source.

Abstract: A driver circuit for operating one or more light emitting diodes(LEDs) is disclosed. An alternating supply current is generated and transformed to an alternating secondary winding voltage. Using rectifier means, such as diodes or synchronous switches, the alternating secondary winding voltage is converted to a substantially constant load current by using a buffer element. The buffer element comprises an output choke, such as an inductor. The power transferred from the power source to the LEDs may be controlled by frequency control of the alternating supply current.

Abstract: A light generating device (20) comprises: —an input for receiving a DC input voltage (Vin) of varying magnitude; —a controllable current source (40); —a switch matrix (30) comprising a plurality of controllable switches (S1-SN); —a plurality of n LEDs (D1, D2, . . . Dn) connected to output terminals of the switch matrix (30); —a controller (50) controlling said switches and controlling the current generated by the current source dependent on the momentary value of the DC input voltage (Vin). The controller is capable of operating in at least three different control states. In a first control state all LEDs are connected in parallel. In a second control state all LEDs are connected in series. In a third control state at least two of said LEDs are connected in parallel while also at least two of said LEDs are connected in series.