Patent ID: 7999492
Filing Date: 2011-08-16
Classification: G09G,H05B

Abstract:
1. A system for driving at least one light-emitting diode (LED) comprising: an output terminal connectable to an anode of the LED and at which an output voltage can be provided for the LED; a driver loop connectable to a cathode of the LED and operable to maintain a LED current flowing through the LED at a desired level, thereby attenuating modulation error attributable to voltage variations at the cathode of the LED, wherein the driver loop comprises a first transistor and a second transistor forming a current mirror between a bias current through the first transistor and the LED current through the second transistor, the LED current having a gain over the bias current; and an adaptive mode change component configured to control the output voltage so that the first and second transistors operate in the saturation region.