US Patent 9271345 LED based lighting application

The present invention relates to a lighting application, the lighting application comprises an LED assembly comprising a serial connection of two or more LED units, each LED unit comprising one or more LEDs, each LED unit being provided with a controllable switch for substantially short-circuiting the LED unit. The lighting application further comprises a control unit for controlling a drive unit and arranged to receive a signal representing a voltage level of the supply voltage, and control the switches in accordance with the signal. The invention further provides for an LED driver that enables to operate a TRIAC based dimmer at an optimal holding current and an LED driver comprising a switchable buffer, e.g. a capacitor.