ADAPTIVE SWITCH MODE LED DRIVER

摘要

PURPOSE: An adaptive switch mode LED driver is provided to minimize a power loss in an LDO(Linear Drop Out Regulator) circuit and maintain currents of each LED string within a limited range. CONSTITUTION: A power converter receives an input voltage and generates an output voltage applied to a first LED string(302). A first channel switch switches on or off the first LED string according to a first duty cycle signal applied to the first channel switch. A first channel regulator receives a first programmed current level signal and controls the current of the first LED string according to the first programmed current level signal. A brightness controller(310) generates the first duty cycle signal for driving the first channel switch and the first programmed current level signal for the first LED string.