The increased popularity of high-power light-emitting diodes (LEDs) over the last several years has challenged electronics engineers to come up with accurate and efficient, yet simple drive solutions. The task is becoming more difficult as the market for LEDs enters the realm of high-powered lights, such as those used in automobile headlights and large liquid crystal display (LCD) backlights. High light-output solutions usually involve large arrays of individual LEDs stacked in series. Conventionally, driving high-power strings with accurate current is at odds with simplicity and efficiency—typically involving an inefficient linear regulator scheme or a more complicated, multiple integrated circuit (IC) switching regulator configuration.

This paper describes a simpler, better method of driving high power LED strings using a low parts count, single IC solution . At the heart of this highly efficient, simple, and accurate solution is the LTC3783 controller IC.