저가형 스마트 LED 조명 구동을 위한 다수의 전류-전압 동시 제어 방법

Abstract

This paper focuses on the Current-Voltage concurrentcontrol method devoted to the multiple LED (light-emittingdiode) string driver. Isolated DC to DC converter withcascaded chopping switch is proposed for smart lightingsystem such as light with sensor or back light unit ofdisplay, which need to control the current of parallelconnected multiple LED stings and regulate DC voltage formicro controller for brightness control. The proposed circuitregulates the current of parallel connected multiple LEDstrings and additional DC voltage output simultaneously. Toverify the performance, experimental results are presentedbased on the prototype board. 5V, 1A voltage mode electricload and two LED strings with different forward voltagesare used for output loads. 23W output power is achievedand measured efficiency is in the range of 85%-87%