Dimming multiple LED strings enables color-tunable luminaires

In many solid-state lighting (SSL) applications, such as architectural, area, and downlighting, color accuracy is very important. Moreover, an increasing number of products support dynamic color tuning — to set the white point or CCT and/or to enable dynamic full-color products. LEDs are ideal light sources for achieving a precise color. The color of LED lighting can be changed by mixing different colors of LEDs, such as red, blue, green, yellow, and white. When mixing LED colors, one or more strings of LEDs needs to be dimmed to realize the desired color mix. There are different methods for achieving LED dimming, so let's consider various dimming techniques used in LED color mixing.