A LED driver circuit is disclosed that has the ability to drive a single series string of power LEDs. The LED driver circuit uses a single stage power converter to convert from a universal AC input to a regulated DC current. This single stage power converter current is controlled by a power factor correction...http://www.google.se/patents/US20080018261?utm_source=gb-gplus-sharePatent US20080018261 - LED power supply with options for dimming
