Patent ID: 8207691

Claim:
Method of driving, by means of single power supply, a number of high-power light-emitting diodes (LEDs), said number of LEDs being divided into two or more groups, each group being separately energizable, said method comprising: a) energizing or de-energizing a supply current from the power supply into a first one of the groups; b) waiting a predetermined wait time period; c) repeating step a) and b) for a second one of the groups; wherein the waiting during the predetermined wait time period establishes a minimum time interval between each load change of the power supply to ensure that the power supply is stabilized before a following one of the groups is energized or de-energized; and d) determining prior to step a), a sequential order by classifying the groups on the basis of a rising or falling desired average current; and wherein step c) comprises: c1) performing steps a) and b) in the energization sequential order for each of the groups to be energized wherein, prior to step d), among the groups a subset comprising groups is excluded from step d) and step c1); and c2) wherein it is determined, after energization according to c1), whether a remaining time up to a next de-energization of one of the groups energized at c1) is at least two wait time periods longer than a desired pulse duration of a group from the subset; c3) if this is the case, the energizing of the relevant group from the subset and de-energization thereof after the desired pulse duration has elapsed; and c4) the repeating of step c2) and c3) as long as not all the groups from the subset have been ON during the desired pulse duration.