An LED color control system with independently changeable illuminance

This paper presents and LED color control system using color control algorithm which adjusts its color temperature and illuminance independently. The proposed system consists of a power factor correction (PFC) circuit, LED driving circuit, and a digital controller. The color temperature variation range of the proposed LED lighting system is 3500-7500°K, and its illuminance one is 500-1500 lux. Within these range, the color temperature and illuminance relative deviations are as low as ±1%.