This application relates to a lighting system comprising a plurality of light emitting diode, LED, circuits, and a power source for providing a drive voltage to the plurality of LED circuits. For each LED circuit, the lighting system comprises a first variable resistance element connected between the respective LED circuit and ground, and a first feedback circuit configured to control a voltage at a first node between the respective LED circuit and the respective first variable resistance element to a first voltage. The lighting system further comprises a current source and a second variable resistance element connected between the current source and ground, wherein each first variable resistance element is configured to attain a resistance value depending on a resistance value attained by the second variable resistance element.