An LED driver for an LED lamp, which also comprises an LED load. The LED driver is adapted to connect to an input source at a first and second terminal. The LED driver comprises a switching arrangement configured to enable a controller to control at least a magnitude and phase of the voltage between the first and second terminals. The phase of the voltage between the first and second terminals may be defined to control an amount of power that flows from the input source to power the LED lamp.

A controller circuit for a set of light emitting diodes (LEDs) includes a linear current source, channel circuitry, and supervisor circuitry. The linear current source is configured to regulate a first current from a supply along a first series path to the set of LEDs. The channel circuitry is configured to control a second current from the supply along a second series path to the set of LEDs, the second series path being in parallel with the first series path and the second series path comprising a drop element coupled in series with the supply and the set of LEDs. The supervisor circuitry is configured to regulate a total current supplied to the set of LEDs using the linear current source and the channel circuitry, the total current comprising the first current and the second current.

A load driving circuit includes a switch circuit and a linear circuit connected in series. The switch circuit has a switching transistor and converts an input voltage into a first output voltage. The linear circuit has a linear device and provides a driving voltage and a driving current for driving the load. The driving circuit controls the switching transistor according to a feedback signal indicative of conducting state of the linear device.

An LED tube lamp with overvoltage protection capability is provided. The LED tube lamp includes a lamp tube, two external connection terminals, a rectifying circuit, a filtering circuit, an LED module, and a protection circuit. The protection circuit is coupled between two input terminals of the LED module and configured to perform overvoltage protection when determining that a voltage level between the two input terminals of the LED module reaches or is higher than a predefined voltage value, wherein the protection circuit includes a diode and the predefined voltage value is in a range of about 40V to about 600V.

A power management system for a lighting circuit may include a grid shifting controller that includes a processor and a connection to an external power source. The power management system may also include a communication interface associated with the grid shifting controller. The grid shifting controller may be configured to provide control information to a processor of at least one grid shifting electrical fixture over the communication interface, the control information being configured to direct the at least one grid shifting electrical fixture on the use of power from the external power source and an energy storage device associated with the at least one grid shifting electrical fixture.

A Light Emitting Diode, LED, based lighting device arranged for emitting a particular emitted light following a Planckian locus in a color space, the LED based lighting device comprises a first LED channel comprising a plurality of LEDs, wherein the first LED channel is tuned to emit light having a first chromaticity in the color space, a second LED channel comprising a plurality of LEDs, wherein the second LED channel is tuned to emit light having a second chromaticity in the color space, a controller for activating the first and the second LED channel such that LED based lighting device emits light having a color in between the first and the second chromaticity in the color space, wherein the LED based lighting device further comprises a third LED channel connected in between the at least two LED channels, wherein the third LED channel comprises one or more LEDs and wherein the third LED channel is tuned to emit light having a third chromaticity in the color space, wherein the third LED channel effectuates that at least one LED of the second LED channel is activated when the first channel is actuated, thereby ensuring that the emitted light follows the Planckian locus in the color space in between the first and the second chromaticity in the color space.

An LED lighting device includes a luminescent device driven by a rectified AC voltage, a current detecting circuit, a current regulating circuit, and a duty cycle detecting circuit. The current regulating circuit is configured to provide a regulating current so that the current flowing through the luminescent device does not exceed the regulating current. The current detecting circuit is configured to monitor the value of the regulating current, and the duty cycle detecting circuit is configured to monitor the duty cycle of the regulating current. The present invention can improve the overall line regulation of the LED lighting device when the rectified AC voltage somehow fluctuates between its upper bound and lower bound.

A dimming control circuit for an LED driver, can include: an adjusting circuit configured to generate an adjusting signal in accordance with a PWM dimming signal; and where a switching state of a power transistor of the LED driver is adjusted in accordance with the adjusting signal and a constant current control signal. A dimming control method for an LED driver, can include: determining a first threshold in accordance with a frequency of the PWM dimming signal and a frequency range of audio noise; generating an adjusting signal having a first duty cycle when a duty cycle of a PWM dimming signal is not greater than the first threshold; and controlling, by the adjusting signal, a switching state of a power transistor in the LED driver, where the first duty cycle is greater than the duty cycle of the PWM dimming signal.

A flexible lighting panel comprising a light-emitting unit with electrical contact pads on a flexible substrate; a flat flexible printed circuit board with a bendable extension tab, wherein the circuit board is located on the opposite side of the light-emitting unit from the substrate; the area of the circuit board, not including the extension tab, is the same or greater than and overlaps the emissive area of the light-emitting unit; and the circuit board has at least two flat electrical connectors in electrical contact with the contact pads of the light-emitting unit; the flat electrical connectors extending along the extension tab of the circuit board for connection to a power source. The light emitting unit can be an OLED. The extension tab can be bent so that the flat electrical connections become accessible in different orientations. The panel can be ultrathin.

The present invention overcomes image defects such as the brightness inclination or smears by reducing the line resistance of a power source bus line which supplies electricity to organic EL elements. A plurality of pixels which are arranged in a matrix array is connected to power source lines, and the plurality of power source lines are connected to a power source bus line. Both ends of the power source bus line are connected to a power source part via a FPC. By supplying electricity to both ends of the power source bus line from the power source part, the line resistance of the power source bus line can be reduced.