傳統的硬切式切換電源供應器，對電磁效應及效率上皆產生不良影響；採用具零電壓切換特性的非對稱半橋脈波調變轉換器，可降低切換開關所帶來的切換雜訊與損失，以提高電路操作頻率及效率。
本篇論文主要研製一300瓦個人電腦電源供應器，輸出規格如下：12 V/16.3 A、5 V/12 A、3.3 V/10.5 A、-12 V/0.4 A。前級使用主動式功率因數修正電路，用以提升電路轉換效率與功率因數，提供穩定電壓。DC/DC架構選用非對稱半橋轉換器以提供12 V輸出，電路具有零電壓切換特性可減少變壓器一次側開關切換損耗。雙組同步降壓型轉換器提供5 V與3.3 V輸出。並設計一返馳式轉換器電路架構，提供輔助電源。

Conventional hard-switching power supply produces electromagnetic interference and presents poor efficiency. By using the Zero-Voltage-Switching (ZVS) asymmetrical half-bridge (AHB) Pulse-Width-Modulation (PWM) converter, switching losses and noise can be reduced, to increase the operating frequency and circuit efficiency.
In this thesis, a 300-watt power supply for personal computer is realized. The output specifications of the developed power supply are: 12 V/16.3 A, 5 V/12 A, 3.3 V /10.5 A, -12 V/400 mA. A power factor corrector circuit is adopted as the pre-regulator to raise the input power factor. The DC/DC converter is implemented by using an asymmetrical half-bridge (AHB) topology to provide a 12-V output. Two synchronous buck converters are used to provide 5-V and 3.3-V outputs. A flyback converter is adopted to provide the auxiliary power supply.

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