Mobile QR Code QR CODE : Journal of the Korean Institute of Illuminating and Electrical Installation Engineers

Journal of the Korean Institute of Illuminating and Electrical Installation Engineers

ISO Journal TitleJ Korean Inst. IIIum. Electr. Install. Eng.
Title A Study on Digital Control Method of LED Luminance
Authors Shin-Ho Kang ; Jeong-duk Ryeom
Page pp.28-34
ISSN 1225-1135
Keywords LED ; Luminance ; Digital Control ; CIE Chromaticity Coordinates
Abstract The pulse width modulation(PWM) method has been generally used as conventional method controlling luminance of LED(light emitting diode). PWM method as analog method with a relation that duty ratio of LED be proportional to luminance has weak point that it is not compatible with digital method of communication etc. In this paper, a experiment is conducted which the luminance of RGB LED be controlled by digital method. For this, the LED digital control system is developed which consist of LED driving circuits and digital logic circuits. By controlling the number of pluses on RGB LED versus digital input, various lighting colors is implemented and digital codes are optimized in order that measured x, y chromaticity coordinates of lighting colors are comprised in the CIE chromaticity coordinates area of targeted lighting colors. The result of this study can be utilized usefully in research on implementing full color by using remote control of LED lamp with digital communication.