Abstract: A LED circuit comprises a current drive circuit for driving a current through the parallel combination of a LED arrangement and an output capacitor. An override arrangement overrides the current level setting to a default current level during start-up, and the override arrangement is disabled when a current flow is sensed by a sensor. The current setting of the driver is ignored until a threshold current is sensed through the LED arrangement. The delay associated with initial start-up charging of the output capacitor is thereby avoided.

Abstract: A lighting circuit has a series connection of a plurality of lighting channels of different output colors, driven by a current source. Some or all of the lighting channels comprise a LED arrangement, a shunt switch in parallel with the LED arrangement and a current leakage path in parallel with the LED arrangement. The current leakage path is used to calibrate the current flowing through the LED arrangement and thereby take account of the LED characteristics.

Abstract: A Light Emitting Diode, LED, driver arranged for driving at least one LED, said LED driver comprising a rectifier arranged for receiving an Alternating Current, AC, supply voltage and for providing an output Direct Current, DC, voltage to said at least one LED, a voltage regulating branch arranged for controlling an LED voltage provided to said at least one LED, via a supply line, wherein said voltage regulating branch is arranged for receiving said DC voltage from said rectifier, wherein said voltage regulating branch comprises, a capacitor arranged for providing said LED voltage to said at least one LED, a current limiter, connected in series with said capacitor, and arranged for charging said capacitor thereby providing said LED voltage and a feedback circuit arranged for controlling the charging of said capacitor by said current limiter, and thereby controlling the LED voltage provided to said at least one LED, by regulating a minimum residual headroom voltage present on a LED current limiter coupled in s

Abstract: A method (500) of configuring a light source array (110) of a system is disclosed. The system further comprising a display (110) and a camera (108), wherein the light source array (110) comprises a plurality of individually controllable lighting units, and wherein the light source array (110) has been positioned relative to the display (110).

Abstract: A system is created for an efficient dimming LED lighting system, and comprising a voltage source, an electronic switch controlled by a pulse width modulation, PWM, driving signal and an LED lighting module connected in series. The LED comprises an LED group and a constant current drive circuit to drive a constant current through the LED group.

Abstract: A LED circuit comprises a current drive circuit for driving a current through the parallel combination of a LED arrangement and an output capacitor. An override arrangement overrides the current level setting to a default current level during start-up, and the override arrangement is disabled when a current flow is sensed by a sensor. The current setting of the driver is ignored until a threshold current is sensed through the LED arrangement. The delay associated with initial start-up charging of the output capacitor is thereby avoided.

Abstract: The invention provides a LED filament lamp (10) comprising: an envelope (11) enclosing a chamber (13) sealed with a stem (12), wherein the stem extends into said chamber; a LED filament structure (14) with at least two individually controllable segments (141-145); a controller (15) configured to receive a control signal and control each of the at least two individually controllable segments based on said control signal, wherein the LED filament structure (14) and the controller (15) are arranged within the chamber (13); a driver circuit (16) arranged outside the chamber, wherein the driver circuit comprises two powerlines (161, 162) extending through the stem (12) or the envelope (11) for powering the LED filament structure (14) and the controller (15), wherein the driver circuit (16) is configured to convey said control signal to the controller (15) via a control line (163) extending through the stem or the envelope.

Abstract: A Digital Addressable Lighting Interface, DALI, enabled communication device for transmitting messages over a communication bus having two communication lines, said device comprising a switch connected between said two communication lines, a controller arranged for controlling said switch for imposing logical communication levels on said communication bus, an energy storage device, connected in series with said switch, and arranged for storing electrical energy flowing from said bus through said switch, a bypass circuit arranged for bypassing said energy storage device when a voltage over said energy storage device is above a predetermined voltage threshold.

Abstract: An LED lighting driver has a switched mode power supply which generates an auxiliary power supply. The auxiliary power supply circuit has a first power supply inductor and a second power supply inductor in series with each other. The second power supply inductor is selectively switched into or out of the auxiliary power supply circuit, thereby varying a transformer ratio to the main energy storage inductor. The switching may be made based on a light output mode or a standby mode being in operation. The standby mode then enables more efficient generation of an auxiliary supply voltage.

Abstract: A lighting circuit makes use of a switch mode power converter to drive a solid state lighting arrangement having a lighting unit and a lighting control switch. A pulse width modulation control signal is applied to the lighting control switch for dimming control with an activation pulse during which the lighting unit is activated. The power converter delivers a triangular current waveform and the activation pulse is delayed until a predetermined point within the triangular current waveform. This ensures that the PWM pulse during which the lighting arrangement is turned on has timing which is synchronized with the timing of the switch mode power converter. The prevents beat frequencies so that visible flicker is avoided.

Abstract: A lighting device (1) is disclosed, comprising a carrier substrate (4) and a heat-transferring element (5). The carrier substrate (4) includes at least a first region (6) and a second region (8). The first region (6) comprises a light-emitting module (7). The second region (8) comprises a communication module (9), which is configured for wireless communication. The heat-transferring element (5) connected with the carrier substrate (4). The carrier substrate (4) partly overlies the heat-transferring element (5) such that at least a part or portion of the first region (6) of the carrier substrate (4) overlies the heat-transferring element (5) and at least a part or portion of the second region (8) of the carrier substrate (4) does not overlie the heat-transferring element (5).

Abstract: A monitor device is provided for monitoring a lighting arrangement of lighting elements of unknown electrical load, and a driver using the monitoring arrangement. A set of duty cycles is applied to switches which control sub-sets of lighting elements thereby to create a desired light output. With this desired duty cycle setting, the current for an individual duty cycle period is monitored, in particular to detect variations in a current plateau level 5 within the individual duty cycle period. This is used to determine a power consumption of the lighting arrangement and to adjust the duty cycles as a function of the detected current. This avoids the need to probe the sub-sets of lighting elements individually in order to determine the nature of the load and its power consumption.

Abstract: The present invention provides an AC/DC converter comprises an input for receiving a rectified AC input signal (Vin), an output for providing a controlled output signal (Vout) to a load (7), a switched mode power converter for transforming the AC input signal (Vin) into the controlled output signal (Vout), wherein the switched mode power converter has an input for receiving a start-up voltage (Vstart) for changing a stand-by mode of the switched mode power converter into an operating mode of the switched mode power converter, a control circuit (5) for receiving a control signal (Vctl), a kick-start power supply (6) for receiving a switch-on signal (Von) to supply the start-up voltage (Vstart) being larger than a power supply voltage (Vsup), an auxiliary power supply (4) for supplying the power supply voltage (Vsup) to the control circuit (5) and the kick-start power supply (6), wherein the control circuit (5) is arranged for activating the switch-on signal (Von) to activate the kick-start power supply (6) for

Abstract: Disclosed is a method and apparatus for overcoming LED flicker caused by an asynchronous control of an LED on or off state and a switched-mode power supply for the LED. A supplementary control system is adapted to override a primary control system for the switched-mode power supply, and control an energy storage inductor of the switched-mode power supply. In particular, in response to an indicated desire to switch the LED on, the supplementary control system sets the current in the energy storage inductor to a predetermined level. In this way, when the LED is switched on, the current through the inductor is known and LED flicker is thereby reduced.

Abstract: A lighting circuit makes use of a switch mode power converter to drive a solid state lighting arrangement having a lighting unit and a lighting control switch. A pulse width modulation control signal is applied to the lighting control switch for dimming control with an activation pulse during which the lighting unit is activated. The power converter delivers a triangular current waveform and the activation pulse is delayed until a predetermined point within the triangular current waveform. This ensures that the PWM pulse during which the lighting arrangement is turned on has timing which is synchronized with the timing of the switch mode power converter. The prevents beat frequencies so that visible flicker is avoided.

Abstract: The present invention provides an AC/DC converter comprises an input for receiving a rectified AC input signal (Vin), an output for providing a controlled output signal (Vout) to a load (7), a switched mode power converter for transforming the AC input signal (Vin) into the controlled output signal (Vout), wherein the switched mode power converter has an input for receiving a start-up voltage (Vstart) for changing a stand-by mode of the switched mode power converter into an operating mode of the switched mode power converter, a control circuit (5) for receiving a control signal (Vctl), a kick-start power supply (6) for receiving a switch-on signal (Von) to supply the start-up voltage (Vstart) being larger than a power supply voltage (Vsup), an auxiliary power supply (4) for supplying the power supply voltage (Vsup) to the control circuit (5) and the kick-start power supply (6), wherein the control circuit (5) is arranged for activating the switch-on signal (Von) to activate the kick-start power supply (6) for

Abstract: A monitor device is provided for monitoring a lighting arrangement of lighting elements of unknown electrical load, and a driver using the monitoring arrangement. A set of duty cycles is applied to switches which control sub-sets of lighting elements thereby to create a desired light output. With this desired duty cycle setting, the current for an individual duty cycle period is monitored, in particular to detect variations in a current plateau level 5 within the individual duty cycle period. This is used to determine a power consumption of the lighting arrangement and to adjust the duty cycles as a function of the detected current. This avoids the need to probe the sub-sets of lighting elements individually in order to determine the nature of the load and its power consumption.

Abstract: The invention provides a method and apparatus for overcoming LED flicker caused by an asynchronous control of an LED on or off state and a switched-mode power supply for the LED. There is provided a supplementary control system adapted to override a primary control system for the switched-mode power supply, and control an energy storage inductor of the switched-mode power supply. In particular, in response to an indicated desire to switch the LED on, the supplementary control system sets the current in the energy storage inductor to a predetermined level. In this way, when the LED is switched on, the current through the inductor is known and LED flicker is thereby reduced.

Abstract: A lighting device (1) is disclosed, comprising a carrier substrate (4) and a heat-transferring element (5). The carrier substrate (4) includes at least a first region (6) and a second region (8). The first region (6) comprises a light-emitting module (7). The second region (8) comprises a communication module (9), which is configured for wireless communication. The heat-transferring element (5) connected with the carrier substrate (4). The carrier substrate (4) partly overlies the heat-transferring element (5) such that at least a part or portion of the first region (6) of the carrier substrate (4) overlies the heat-transferring element (5) and at least a part or portion of the second region (8) of the carrier substrate (4) does not overlie the heat-transferring element (5).

Abstract: An LED lighting driver has a switched mode power supply which generates an auxiliary power supply. The auxiliary power supply circuit has a first power supply inductor and a second power supply inductor in series with each other. The second power supply inductor is selectively switched into or out of the auxiliary power supply circuit, thereby varying a transformer ratio to the main energy storage inductor. The switching may be made 5 based on a light output mode or a standby mode being in operation. The standby mode then enables more efficient generation of an auxiliary supply voltage.