System and method for controlling a multi-string light emitting diode backlighting system for an electronic display

摘要

The present invention relates to displays that use LED strings for backlighting. A lead string is provided with continuous drive voltage and the non-lead strings are provided with pulsed drive pulses. The string having the highest forward voltage is selected as the lead string. Feedback information indicative of the currents flowing through the non-lead strings is used to determine the duty cycles of the voltage pulses provided to drive the non-lead strings. The non-lead strings are controlled using pulsed drive voltages to minimize power dissipation in the circuit.