A low-cost high-efficiency linear LED driver with concave current control

This paper presents a high-efficiency and low cost linear LED driver with concave current control method for low power applications. In order to achieve a high efficiency of the linear LED driver, control methods with three different current shapes, namely, traditional flat and convex current shape, proposed concave current shape, have been discussed and compared via theoretical analysis. It is concluded that the proposed concave current control method has the highest efficiency among these three methods for different input voltage conditions. The design considerations have been provided. Finally, experimental results verify the proposed method.