APPARATUS FOR DRIVING LED STRINGS

摘要

The present invention relates to an apparatus for driving LED strings, characterized by comprising: one or more hysteresis comparators for being activated to output current source control signals from when the LED strings are turned on until current source operations stabilize and a constant current flows; minimum driving voltage-providing current sources, driven by the activated current source control signals, for performing a sinking operation for a feedback terminal; a minimum voltage selection unit for selecting a minimum voltage level from among current source terminal voltages corresponding to current sources of the LED strings; a current amplifier for amplifying a current corresponding to an output voltage of the minimum voltage selecting unit to perform a sinking operation or a sourcing operation for the feedback terminal; a direct current voltage regulator for raising or lowering a driving voltage according to the sinking or sourcing operation of the current amplifier after outputting the driving voltage at at least a predetermined level more according to the sinking operation of the minimum driving voltage that provides a current source when the driving voltage is outputted to turn on the LED strings on the basis of an input voltage.