A 20W Single Ended Primary Inductor Converter Power Factor Correction Circuit in Critical Conduction Mode with Constant On Time

This paper proposes a Single Ended Primary Inductance Converter Power Factor Correction circuit (SEPIC PFC). The proposed SEPIC PFC is operated in CRitical Conduction Mode (CRM) with Constant On Time (COT). Due to CRM operation, the SEPIC switch is turned on at Zero Current Switching (ZCS), thus, reducing the switching losses. A unity power factor of line current is nearly achieved, resulting in low Total Harmonics Distortion (THD), over the universal line voltage (90V-260V). The simulation results show that the proposed design does have a smoothed line current and it is suitable for low power applications e.g., Laptops and mobiles chargers.