Multiple LED strings with capacitor current balancing and auto-restart function

This paper presents a precise and cost-effective capacitor-based current balancing scheme for multiple LED strings application. Using capacitor´s Ampere-Second balance characteristic, the precise current balancing of N LED Strings can be achieved by N-1 Capacitors. Besides, an auto-restart scheme is also presented in this paper to achieve the open circuit protection and to automatically restart the LED String when the false of open circuit is removed. Finally, a LED Driver with proposed current-balancing and auto-restart method is verified experimentally.