Patent ID: 7821237

Claim:
A power factor corrector (PFC), comprising: a switch-mode boost stage having a switch and an inductor coupled to the switch wherein the switch-mode boost stage receives a rectified line input voltage and provides a link output voltage and wherein a sensed current is observed from the switch-mode boost stage; and a target current generator for receiving the link output voltage and for generating a target current proportionate to the rectified line input voltage; a comparator for receiving a target current value representative of the target current and a sensed current value representative of the sensed current and outputting a two-level current comparison result signal; and a finite state machine responsive to the two-level current comparison result signal, generating a switch control signal that has a duty cycle which is adjusted for controlling the switch so that the sensed current is approximately proportionate to the rectified line input voltage, such that power factor correction is performed.