Patent ID: 7971955

Claim:
A control unit for a printing apparatus, the printing apparatus having a plurality of heat sources, each of the plurality of heat sources being operable at an individual power level, the control unit comprising a scheduler; the control unit being configured to control the power supplied to the plurality of heat sources such that, at each instant, the sum of the delivered individual power levels to the plurality of heat sources is less than or equal to a maximum allowable power level; and the control unit being configured to control the power delivered to the plurality of heat sources on the basis of scheduled instants within sequential cycles, and for each of said sequential cycles: the schedule receiving a requested power pulse duration for each of the plurality of heat sources; the schedule scheduling for each instant within said sequential cycle to which of the plurality of heat sources the power is to be delivered, based on the individual power levels of the plurality of heat sources and the requested power pulse durations; and the control unit being configured to deliver the power according to the scheduled instants within said sequential cycle.