本文實現一新型交錯式高降壓直流-直流轉換器，應用耦合電感、切換式電容與交錯式等技術，主要應用於低壓大電流等電壓調節器。與傳統的兩相式降壓型轉換器相比，新型轉換器將有效佔空比提高了三倍，降低了功率元件上的電壓應力。該新型轉換器能夠通過兩相之間的耦合電感及交錯式並聯技術向輸出端提供大電流及平衡兩相之間的電流達到低電流漣波輸出的特性。
在論文中，推導出了穩態特性如電壓增益比、功率元件承受的電壓和電流應力與輸出電壓漣波均進行了詳細的推導，並且通過軟體驗證其穩態特性。最後，通過使用控制器TMDSDOCK28035，實現了具有48V輸入電壓，1V輸出電壓和30W輸出功率的電路，用以驗證轉換器架構及理論之可行性。其滿載效率為79.3%，最大效率於輸出功率3 W時可達90.2%。

This thesis proposes a novel nonisolated converter topology with high step-down conversion ratio for high current and low voltage application, such as voltage regulator modules (VRM). The proposed converter is based on several existed techniques such as coupled-inductor, switched capacitor and interleaved technique. Compared to a conventional two-phase buck converter. The novel converter is capable of delivering larger current to the output load by two coupled-inductors with interleaved technique. Futhermore, it features an inherent current sharing capability, which can balance the load current and reduce the output current ripple.
The steady-state characteristics, such as high-step down voltage gain, voltage and current stress on the power components, and output voltage ripple are derived in the thesis. Simulation results are obtained by software. Lastly, by using controller TMDSDOCK28035, a converter with 48V input voltage, 1V output voltage and 30W output power is implemented to prove the feasibility of proposed converter. The highest efficiency is around 90.2% when operating at 3 W and the efficiency is 79.3% at full load.

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