Patent ID: 7688041

Claim:
A power factor correction control apparatus connected to a AC/DC converter to emulate a resistive load on the input power line wherein the converter provides a sense signal IFB which is proportional to the current drawn from the input power line and a sinusoidal signal IREF which is proportional to its loading and receive a switch signal G and the output power of the converter is proportional to the duty cycle of the switch signal, comprising: a summer, receiving the sense signal IFB for generating an error signal IERR in response to compare the said sense signal with the sinusoidal signal IREF from the converter; an averaging unit, coupled to the summer for averaging the signal IERR thereby yielding a signal Q; a ramp signal generator, starts generating a ramp signal RAMP when the switch signal G of the converter falls from high to low; a comparator, receiving the Q signal from the averaging unit and the RAMP signal from the ramp signal generator for generating a triggering signal EN in response to comparing the signal Q with the RAMP signal; and a pulse generator, coupled to the comparator for generating the said switch signal G of the converter when the triggering signal from the comparator rises from low to high.