Abstract: The present invention is a power supply apparatus capable of providing one or more individually controllable high voltage outputs for various components within an electrophotographic printing machine. Receiving power from an input power source, the power supply apparatus produces various high voltage outputs, wherein each output is capable of providing a range of high voltage potentials. The individual high voltage outputs are regulated by a microcontroller which receives an analog voltage signal from a voltage sensor and produces a voltage control signal which is then used to regulate the outputs in a conventional manner for resonant- or switching-type power supplies. The microcontroller regulates the output potentials by varying the voltage control signals for each of the outputs as a function of the difference in magnitude between the analog voltage signal and a voltage set-point value associated with the output.