Patent ID: 8502472

Claim:
A light emitting diode (LED) driving apparatus, comprising: a power converter, having a power transistor switch, and receiving an input voltage and performing power conversion through the power transistor switch, so as to output a driving voltage at an output terminal of the LED driving apparatus; a voltage sample-and-hold and comparison circuit, coupled to the output terminal for receiving a feedback voltage generated according to the driving voltage, and receiving a dimming status signal and entering a sample-and-hold mode or a comparing mode according to the dimming status signal, wherein the voltage sample-and-hold and comparison circuit samples and holds the feedback voltage to obtain a pre-storage voltage in the sample-and-hold mode, and compares the pre-storage voltage with the feedback voltage to obtain a comparison result in the comparing mode; and a pre-charge clock generator, coupled to the voltage sample-and-hold and comparison circuit, for receiving the pre-charge enable signal and a clock signal to generate a pre-charge clock signal to control the power transistor switch.