A LED driver adopts one power stage to provide a constant drive current to drive a load, and to provide different power supply voltages to power a smart module according to a dimming signal input by users through the smart module. The LED driver provides high performance with simple circuit structure.

System and method for controlling one or more light emitting diodes. For example, the system for controlling one or more light emitting diodes includes a current regulation circuit coupled to a cathode of one or more light emitting diodes. The one or more light emitting diodes include the cathode and an anode configured to receive a rectified voltage. Additionally, the system includes a control circuit coupled to the cathode of the one or more light emitting diodes. The control circuit is configured to receive a first voltage from the cathode of the one or more light emitting diodes, compare a second voltage and a threshold voltage, and generate a control signal based at least in part on the second voltage and the threshold voltage. The second voltage indicates a magnitude of the first voltage.

optoelectronic circuit intended to receive a variable voltage containing an alternation of rising and falling phases. The optoelectronic circuit includes light-emitting diodes and a switching device capable of allowing or of interrupting the flowing of a current through each light-emitting diode. Each light-emitting diode is covered with a photoluminescent layer. The photoluminescent layer covering at least one of the light-emitting diodes includes at least one first luminophore having a first decay constant and at least one second luminophore having a second decay constant different from the first decay constant.

The present techniques generally concern methods and systems for managing undesired effects in an electrical grid, which may include rapid voltage change(s) and/or flicker(s). The system includes an event detection module operatively connected to a plurality of horticultural light sources. The event detection module is configured to determine a power usage of the horticultural light sources, based on illumination conditions, detect an event affecting the illumination conditions, determine whether the event causes the undesired effects in the electrical grid, based on an evolution of the power usage of the horticultural light sources in response to the event, and send illumination instructions to the horticultural light sources to adjust the power usage of the horticultural light sources, if the event causes the undesired effects.

The present techniques generally concern methods and systems for managing undesired effects in an electrical grid, which may include rapid voltage change(s) and/or flicker(s). The system includes an event detection module operatively connected to a plurality of horticultural light sources. The event detection module is configured to determine a power usage of the horticultural light sources, based on illumination conditions, detect an event affecting the illumination conditions, determine whether the event causes the undesired effects in the electrical grid, based on an evolution of the power usage of the horticultural light sources in response to the event, and send illumination instructions to the horticultural light sources to adjust the power usage of the horticultural light sources, if the event causes the undesired effects.

An LED tube lamp comprises: a glass lamp tube; a light diffusion layer disposed on a surface of the glass lamp tube; an LED light strip, which comprises a fixing portion and an extending portion disposed in the glass lamp tube; a plurality of LED light sources mounted on the fixing portion of the LED light strip; a fixing structure disposed between the fixing portion and the inner circumferential surface the glass lamp tube; a power supply module disposed on the fixing structure and electrically connecting to the LED light strip and two end caps attached to two ends of the glass lamp tube respectively. The fixing structure comprises a first end fixedly connected to the inner circumferential surface of the glass lamp tube and a second end fixedly connected to the fixing portion of the LED light strip and not connected to the extending portion of the LED light strip.

An LED tube lamp comprises: a glass lamp tube; a light diffusion layer disposed on a surface of the glass lamp tube; an LED light strip, which comprises a fixing portion and an extending portion disposed in the glass lamp tube; a plurality of LED light sources mounted on the fixing portion of the LED light strip; a fixing structure disposed between the fixing portion and the inner circumferential surface the glass lamp tube; a power supply module disposed on the fixing structure and electrically connecting to the LED light strip and two end caps attached to two ends of the glass lamp tube respectively. The fixing structure comprises a first end fixedly connected to the inner circumferential surface of the glass lamp tube and a second end fixedly connected to the fixing portion of the LED light strip and not connected to the extending portion of the LED light strip.

A light-emitting diode (LED) lighting device driver with improved luminous performance is provided, which includes a driving circuit and a current ripple reduction circuit. The driving circuit outputs a driving current. The current ripple reduction circuit receives the driving current and reduces the current ripple of the driving current to generate an output current in order to drive a light-emitting module. The current ripple reduction can effectively depress the current ripple of the driving current outputted from the driving circuit in order to generate the output current and then drive the light-emitting module by the output current. Thus, the luminous performance of the light-emitting module can be significantly improved with a view to achieve energy saving and conform to environmental protection requirements.

A circuit board configuration adapted to carry electronic components of a power supply module is provided. The circuit board configuration comprises: a first circuit board, having a first plane configured to dispose and connect a part of the electronic components; and a second circuit board, electrically connected to the first circuit board and having a second plane configured to dispose and connect another part of the electronic components, wherein at least one of the first and the second circuit boards is disposed, perpendicular to an axial direction of the lamp tube, in an interior space formed by the lamp tube and at least one of the two end caps, so that the a direction normal to the first and the second planes is substantially parallel to the axial direction of the lamp tube.

A two-stage driver supplies current to a light emitting diode (LED) load. The driver includes a first stage and a second stage. The second stage is configured to generate a desired current through the LED load. The second stage has a flyback converter having a flyback transformer with a primary winding and a secondary winding. The primary winding is turned on and off by a gating signal. An induced voltage in the secondary winding rings when a current in the secondary winding is discharged. The flyback converter is configured to turn on the primary winding only during a detected valley in the ringing of the secondary winding. If the primary winding is turned on during a detected valley different from the previous detected valley, a valley jump is detected and the switching frequency is adjusted.