Asymmetrical Flyback Converter in High Density SMPS

In recent years the number of electronic devices, such as mobile phones, tablets, laptops, etc., have increased dramatically. The need for a versatile adapter which can be used for several devices, with high efficiency and minimum size to ensure minimal waste of energy and electronic parts, is highly desired. An innovative USB-PD adaptor, based on the asymmetrical PWM flyback topology will be proposed, which is able to supply 65W, has peak efficiency close to 95% and a minimum of 93% at full load over input voltage and a power density of 20W/inch3 cased. The topology selection, dimensioning and control method will be explained in this paper, and measurement results on a prototype will be presented