在電源系統中，多組輸出一直是使用者的基本需求之一。以往在應用上，並不要求所有的輸出組均具有良好的穩壓調節率，因此在設計上，是以主輸入組來做迴授控制，以獲取良好的穩壓輸出，至於其它各組則由變壓器線圈間的耦合來得到要求的輸出電壓，這種電源系統只能應用在對電壓調節率沒有嚴格要求的地方。
為了改善電壓調節率，發展出磁放大器來做為後置穩壓器以成為最佳的解決方案。以往磁放大器被廣泛的用在順向式多組輸出電源系統中，但是其在每個輸出組都必須有一個洩放電阻來確保在輕載時的不穩定，如此就造成功率浪費在洩放電阻上。為了達到低成本且又兼具良好電壓調節率的要求，返馳式架構加上磁放大器來做後置穩壓調節控制就成為最佳的控制架構。利用磁放大器的特性來使變壓器二次側的各組電流產生依序輸出的效果，達到輸出穩壓的效果。在低於100瓦的多組輸出電源系統選擇上，本組合架構可完全的取代順向式架構以符合低成本要求且又能使各輸出組達到穩壓的效果。

In the power supply system, multi-output is always one of the basic requirement for the user. In earlier times, it did not request all the outputs of a power supply system with an excellent voltage regulation in the application. Basically one of the outputs is chosen as feedback control for stabilizing the system. As for the other outputs, their output voltages were obtained by varying the transformer turns ratio. This kind of power system design is only used for the application which doesn’t request highly accurate voltage regulation.
For improving the voltage regulation, the MagAmp used as post regulation has become the best solution. The MagAmp was popularly used in the forward multi-output system in the past. Since each output must have a bleed resistor to ensure the instability in the light load condition, it then causes dissipation on the resistor. In order to achieve a low cost and an excellent voltage regulation, it is the best choice to add a MagAmp used as post regulation for the flyback converter. The ”time share” technique uses MagAmp in flyback converter can provide tightly regulated outputs, and a multi-output power system of 100W flyback circuits is examined. This proposed converter can totally replace the traditional forward converter, and it also can archive of low cost and the stable output voltage for each output.

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