Abstract: A controller having dedicated fuser circuitry and a processor for controlling the fuser heating element. The dedicated fuser circuitry interconnects an input voltage source to the processor through a low voltage power supply to provide a reference signal and a sample DC voltage signal representative of the input voltage source. The processor provides a digital signal to activate a triac connected to the fuser heating element. The triac, selectively gates the input voltage source across the heating element. A plurality of ranges of digital signals and a plurality of corresponding triac activation rates are provided for variations in input voltage. A digital signal related to a particular value of the input voltage source lies within one of the plurality of ranges determining the particular activation rate of the triac.