This application note presents practical step-by-step design considerations for a Boundary-Conduction-Mode (BCM) Power-Factor-Correction (PFC) converter employing Fairchild PFC controller, FAN7930. It includes designing the inductor and Zero-Current- Detection (ZCD) circuit, selecting the components, and closing the control loop.
This document presents practical step-by-step design considerations for a Boundary-Conduction-Mode (BCM) Power-Factor-Correction (PFC) converter employing the Fairchild FAN7930 PFC controller. It covers designing the inductor, Zero-Current-Detection circuit, component selection, and closing the control loop.
The maximum switching frequency of the FAN7930 is limited to 300kHz.
The example uses a universal input range of 90~265Vac, an output voltage of 400V, and requires a hold-up time where voltage does not drop below 330V during one line cycle.
The design requires a minimum switching frequency higher than 40kHz.