Disclosed is an LED driving apparatus. The LED driving apparatus comprises an LED driving circuit, a power supply unit for supplying a driving voltage to the LED driving circuit, a voltage ripple controller located between the LED driving circuit and the power supply unit, and a switching unit for controlling a voltage supplied to the LED driving circuit by turning on or off the voltage ripple controller according to a duty ratio of a pulse width modulation (PWM) dimming signal.

In described examples, a system (e.g., a light-emitting diode dimmer system) includes a switching device coupled to a switching controller. The switching controller generates a control signal, which includes a low frequency signal (e.g., for controlling a dimming function) and a switching signal. An active electromagnetic interference filter (AEF) is coupled to the DC source. An active shunt is coupled to a power input node of the switching device and is configured to selectively couple a shunt current to the power input node of the switching device in synchronization with the low frequency signal (e.g., which can reduce, if not also eliminate, a saturation time of the AEF and improve the performance of the AEF).

In described examples, a system (e.g., a light-emitting diode dimmer system) includes a switching device coupled to a switching controller. The switching controller generates a control signal, which includes a low frequency signal (e.g., for controlling a dimming function) and a switching signal. An active electromagnetic interference filter (AEF) is coupled to the DC source. An active shunt is coupled to a power input node of the switching device and is configured to selectively couple a shunt current to the power input node of the switching device in synchronization with the low frequency signal (e.g., which can reduce, if not also eliminate, a saturation time of the AEF and improve the performance of the AEF).

The present invention provides a power control circuit which has a timing unit used for timing an elapsed time of current half cycle of the phase-cut AC power supply signal, outputting a current accumulated timing duration, and outputting a first control signal at a starting moment when a starting point of a half cycle of the AC power supply signal is detected; a regulating unit connected to the timing unit and comprising a temporary storage module, wherein a final reference time interval is stored in the temporary storage module, and when the current accumulated timing duration reaches the final reference time interval, the regulating unit outputs a second control signal; and a control unit connected to the detection unit and the regulating unit and used for controlling current in a load based on the first control signal and the second control signal.

The present invention provides a power control circuit which has a timing unit used for timing an elapsed time of current half cycle of the phase-cut AC power supply signal, outputting a current accumulated timing duration, and outputting a first control signal at a starting moment when a starting point of a half cycle of the AC power supply signal is detected; a regulating unit connected to the timing unit and comprising a temporary storage module, wherein a final reference time interval is stored in the temporary storage module, and when the current accumulated timing duration reaches the final reference time interval, the regulating unit outputs a second control signal; and a control unit connected to the detection unit and the regulating unit and used for controlling current in a load based on the first control signal and the second control signal.

A lighted accessory and/or corresponding method of installation seamlessly replace an original equipment manufacturer (OEM) lighting apparatus and/or accessory. The accessory includes a front side and back side with a circuit board positioned therebetween. One side of the accessory includes translucent portion(s). The circuit board includes a plurality of light emitting diodes (LEDs) which are aligned with the translucent portion of the front side of the accessory such that when the LEDs are illuminated, light is emitted from the accessory. The circuit board also includes at least one microcontroller and a radio-frequency interference filter circuit wherein the microcontroller controls the LEDs and the radio-frequency interference filter circuit mitigates RF emissions.

A circuit arrangement comprises an LED chain comprising multiple LEDs and bypass switching elements, wherein each LED is assigned to one of the bypass switching elements, and the bypass switching elements each have a driver terminal, wherein each of the bypass switching elements is configured to bypass the LED of the LED chain that is associated with the bypass switching element based on a voltage at the driver terminal that is associated with the bypass switching element; and a switch, wherein the driver terminals of the bypass switching elements are connected to the switch via a common node, the switch being configured to discharge a capacitor of a constant current source that can be connected to the LED chain based on a voltage applied to the node. A circuit comprises the circuit arrangement.

A circuit arrangement comprises an LED chain comprising multiple LEDs and bypass switching elements, wherein each LED is assigned to one of the bypass switching elements, and the bypass switching elements each have a driver terminal, wherein each of the bypass switching elements is configured to bypass the LED of the LED chain that is associated with the bypass switching element based on a voltage at the driver terminal that is associated with the bypass switching element; and a switch, wherein the driver terminals of the bypass switching elements are connected to the switch via a common node, the switch being configured to discharge a capacitor of a constant current source that can be connected to the LED chain based on a voltage applied to the node. A circuit comprises the circuit arrangement.

A ripple reduction circuit for reducing a current ripple of a driver is provided. The driver circuit comprises an input section with input contacts for connecting the driver circuit to an AC power supply providing an AC input current and a power section for providing an output power, the power section comprising a power transformer and a power switch connected in series with a primary winding of the power transformer. The driver circuit further comprises a ripple reduction circuit with an inductance and a capacitive and two diodes, the ripple reduction circuit being configured such that, in operation, the inductance and the capacitance can be alternately charged and discharged, depending on the switching state of the power switch.

The embodiments of the present application disclose a booster circuit and a driving method thereof, a backlight module and a display device. The booster circuit includes: a booster sub-circuit and an oscillation elimination sub-circuit; wherein the booster sub-circuit includes a power supply element, an inductor, and a first switch; the booster sub-circuit is configured to provide, at a connection node, a voltage higher than a voltage provided from the power supply element; and wherein a parasitic capacitance occurs between the connection node and a ground terminal; the oscillation elimination sub-circuit is configured to prevent a current generated when the parasitic capacitance discharges from flowing through the inductor so as to eliminate an oscillation generated between the parasitic capacitance and the inductor.