AN-4140 Datasheet (Fairchild Semiconductor) - Transformer Design Consideration

AN-4140, Transformer Design Consideration

www.fairchildsemi.com AN-4140 Transformer Design Consideration for Offline Flyback Converters Using Fairchild Power Switch (FPS ™) 1.

Introduction For flyback coverters, the transformer is the most important factor that determines the performance such as the efficiency, output regulation and EMI.

Contrary to the normal transformer, the flyback transformer is inherently an inductor that provides energy storage, coupling and isolation for the flyback converter.

In the general transformer, the cur

AN-4140 Features

* EE EI -Low cost EFD EPC EER -Low profile -Large winding window area -Various bobbins for multiple output -Large cross sectional area -Relatively expensive Typical Applications Aux. power Battery charger LCD Monitor CRT monitor, C-TV DVDP, STB PQ Table 1. Features and typical applications of variou