Design of a high power density ultra-thin switching power supply

Abstract

The planar transformer has the advantages of small size, low leakage inductance, low conversion efficiency, and good heat dissipation performance. The design scheme of the planar transformer is very suitable for the design of ultra-thin switching power supplies. Small-sized ultra-thin switching power supply with high power density of 19.8 V(2.31 A) is developed using a planar transformer. Flyback converter is used as the main circuit and SG6742 is used as the control chip,parameter selection of transformer and PCB design of planar transformer are given. The circuit test results show that the flyback power supply has a wide input voltage of 88 V～264 V, the output voltage ripple is small, and the efficiency is greater than 87% under a wide voltage input range.

Keywords

• switching power supply
• flyback converter;planar transformer
• high power density