因新能源法規規範著更有效的利用能源，產業的發展趨勢也要求體積小型化、更薄型化以及熱處理的改進，致使提高電源供應器的操作效率已成為重要的議題。更高的效率、更高的功率密度及更高的元件密度也成為電源供應器常見的設計及應用。LLC 諧振轉換器已經廣泛的使用在越來越多的交換式電源供應器的設計中，因為LLC諧振轉換器擁有高操作效率、低輻射干擾放射及有能力可達到高功率密度。另一方面，數位化電源透過監控能力可提供的靈活的可適應性與彈性以滿足任何複雜的電源要求，以正確的執行處理並適應系統條件。
　　本文提出的數位控制LLC諧振轉換器的設計，LLC諧振拓樸架構可允許功率開關操作在零電壓切換，因此可以降低功率開關的交換損失，提高操作效率。數位控制器我們採用Mircochip公司所生產的dsPIC33FJ16GS502微控制器替代市售的LLC諧振轉換器IC。而為了進一步提高LLC諧振轉換器的操作效率，我們也採用了輸出同步整流。本文將會擬定一個系統並詳細的敘述硬體與韌體元件的設計。最後本文實驗結果將以驗證其正確性。

Due to the introduction of new regulations concerning more efficient use of energy and the present industry trends that demand smaller size, thinner profile and improved thermal management, improving power supply efficiency is essential. Higher efficiency, higher power density, and higher component density have become common in power supply designs and their applications.　LLC resonant converters are becoming increasingly popular in switched mode power supply design due to its high efficiency, low level of EMI emissions, and its ability to achieve high power density. On the other hand, digital power can provide intelligent adaptability and flexibility to satisfy any complex power requirement with the straightforward ability to monitor, process and adapt to system conditions.
In this thesis, the design of a digitally-controlled LLC resonant converter is presented. The LLC resonant topology allows for zero voltage switching of the main switches, thereby dramatically lowering switching losses and boosting efficiency. A digital signal controller dsPIC33FJ16GS502 from Microchip corp. is utilized as the digital controller of the LLC resonant converter. In order to further improve the efficiency of the presented LLC resonant converter, synchronous rectification is also implemented. Detailed description about the hardware and firmware parts of the proposed system will be presented first and the design considerations will be discussed. Finally, experimental results will be presented to validate the correctness of the proposed system.

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