A device includes a plurality of first LEDs, a plurality of second LEDs, at least one controllable current source that is configured to generate at least one bias current for driving the plurality of first LEDs and the plurality of second LEDs, and a plurality of measurement circuits, each of which is configured to measure a current-voltage (I-V) performance characteristic of at least one of the plurality of first LEDs. A property of a first bias current of the at least one bias current is determined as a function of at least two measurements of the I-V performance characteristic of the at least one of the plurality of first LEDs, and the at least two measurements of the I-V performance characteristic are acquired while the first bias current is applied to the at least one of the plurality of first LEDs and the plurality of second LEDs.