Adaptive Peak Average Current Control LED Driver for Automotive Lighting

Abstract

This letter describes a new average current control dc–dc LED driver suitable for automotive pixel (matrix) lighting. Current is sensed only on an integrated high side switch and peak current is controlled to achieve required average output current independent of tolerances of components and parameters other than the current sensing itself. Fast reaction to output voltage changes required by the pixel light operation is achieved by using a constant ripple control with an off time inversely proportional to the output voltage.