Cascaded PFC and resonant mode power converters

Abstract

A power supply includes a PFC (power factor correction) converter that has an input and an output. The PFC converter input is coupled to an input of the power supply. The power supply also includes a resonant mode converter that has an input and an output. The resonant mode converter input is coupled to the PFC converter output and the resonant mode output is coupled to an output of the power supply. A control unit is also included in the power supply and is coupled to receive a feedback signal that is representative of the output of the power supply. The control unit is coupled to provide control signals coupled to control switches of the resonant mode converter at a controlled switching frequency to control the output of the power supply. The control unit is further coupled to provide a PFC control signal coupled to control a switch of the PFC converter at a switching frequency that is harmonically related to the controlled switching frequency.

Dependencies are inferred from the claim text.