2013 Volume 10 Issue 4 Pages 20130070
This paper presents a dimming technique for light emitting diode (LED), which improves the resolution of luminous intensity, luminous efficiency and extends the life of device. The presented method quantifies corresponding variation from light sensor into binary representation by a pulse width modulator (PWM) and multilevel generator. After that, a digital filter is further used to perform interpolation on converted binary codes enhancing the length of signal. Through controlling the binary-weighted current regulation, the presented method provides 8-bit resolution on adjusting luminous intensity.