Methods and apparatus for controlling series-connected LEDs. Two or more LEDs are connected in series between a first node and a second node, wherein a series current flows between the nodes when an operating voltage is applied across the nodes. One or more controllable current paths are connected in...http://www.google.de/patents/US7781979?utm_source=gb-gplus-sharePatent US7781979 - Methods and apparatus for controlling series-connected LEDs
