Patent ID: 8299724

Claim:
An integrated circuit comprising: a first terminal; a second terminal; a power switch coupled to selectively couple the first and second terminal; a control circuit adapted to control the power switch based at least in part on an electrical characteristic of a string of Light Emitting Diodes (LEDs) external to the integrated circuit and an input voltage, wherein during a first time a current flows through the power switch, wherein during a second time the current does not flow through the power switch, and wherein the input voltage during the second time is higher than the input voltage during the first time; and a protection switch, wherein the string of LEDs has a first end node and a second end node, wherein an AC voltage signal having a waveform substantially identical to a waveform of a rectified AC sine wave is present across the string of LEDs between the first and second end nodes, wherein the protection switch is coupled to the second end node, wherein the string of LEDs consumed power, and wherein when an LED string current flows through all of the LEDs of the string of LEDs the protection switch limits the LED string current so as to reduce a power consumed by the string of LEDs while an AC voltage signal is at a maximum.