Method and apparatus for controlling driving current of illumination source in a display system

A programmable current controller comprising:

• a programmable interface configured to program a digital reference in a memory, wherein the digital reference corresponds to a predetermined driving current for at least one illumination source;
• a digital-to-analog converter coupled to the programmable interface and configured to convert the digital reference into a first electrical parameter;
• a comparator coupled to the programmable interface and configured to
• compare the first electrical parameter with a second electrical parameter corresponding to an operating driving current of the at least one illumination source, and
• generate a driving bias current;
• and
• a current regulator coupled to the comparator and configured to
• regulate the operating driving current of the at least one illumination source according to the driving bias current, wherein the driving bias current corresponds to a difference between the first and second electrical parameters.