Control of a power factor corrected switching power supply

The specification may disclose a switching power supply operated in a discontinuous current power factor corrected mode, having multiple boost circuits or boost modules, and controlled by a digital signal processor. The digital signal processor may implement a control scheme whereby the duty cycle of the switching signals applied to the boost modules may be controlled, in part, by the amount of power delivered to the load in the previous half cycle of the source voltage. In another aspect, an output voltage correction to the switching signals may be applied at the end of each half cycle, which may result in voltage correction at twice the source frequency.