Digital controller based power factor correction circuit

摘要

A power factor correction circuit utilizes a digital controller string comprised of an analog-to-digital converter, which is input to a digital compensator followed by a pulse width modulation circuit for generating a switching pulse. The loop current in a regulator circuit such as a boost regulator is sensed and input to one side of a differential analog-to-digital converter, the other side thereof providing a digital reference current. This digital reference current is derived from comparing the input AC voltage to the regulator with the DC output voltage and processing these two voltages with a PFC algorithm to provide this reference voltage.