ON Semiconductor NCP1680 Critical Conduction Mode (CrM) Totem Pole Power Factor Correction (PFC) Controller ICs are designed to drive the bridgeless Totem Pole PFC topology. The bridgeless Totem Pole PFC consists of two Totem Pole legs: a fast switching leg driven at the PWM switching frequency and a second leg that operates at the AC line frequency. This topology eliminates the diode bridge present at the input of a conventional PFC circuit, allowing significant improvement in efficiency and power density.
