METHOD OF CONTROLLING AN LED SOURCE AND AN LED BASED LIGHT SOURCE

摘要

An LED driver configured to power a plurality ofLEDs having a different colour or colour spectrum is described,the LED driver comprising: - a power converter configured to supplypower to the plurality of LEDs and - a control unit, the controlunit comprising: an input terminal configured to receive aninput signal representing a desired colour set-point; a processingunit configured to: determine a MacAdam ellipse for the desiredcolour set-point; determine a required intensity or current for eachof the plurality of LEDs so as to achieve the desired colour set-point;determine a colour shift direction for the colour set-point,based on the determined required intensities or currents; select amodified colour set-point based on the colour shift direction andthe MacAdam ellipse; determine a required supply current for eachof the plurality of LEDs so as to achieve the modified colour set-point;determine a control signal for the power converter so as togenerate the required supply currents; and wherein the control unitfurther comprises an output terminal for outputting the control signalto the power converter.