A light emitting diode (LED) system implements a LED driver to drive a set of one or more LED strings. The LED driver includes a voltage source to provide an adjustable output voltage to a head end of each LED string of the set for a first duration and a second duration following the first duration. The LED driver further includes a feedback controller to control the voltage source to adjust the output voltage for the second duration based on a digital code value generated from a minimum tail voltage of one or more tail voltages of the set at a sample point of the first duration. The LED driver further includes a power controller to temporarily enable one or more components of the feedback controller for a sample period of the first duration, the sample period comprising the sample point.