本論文提出並探討具有快速動態響應降壓轉換器之適應性導通時間控制電路。適應性導通時間控制電路因操作在輕載時，可以有效降低切換損失而被廣泛使用來優化輕載效率。近幾年來，電源轉換器已具有快速動態響應之趨勢，因為透過改善負載暫態響應而可以減少輸出電容之使用，特別是對於中央處理單元與具有高電流變化率之應用。本論文主要的貢獻於快速動態響應電路之開發與分析，並可被應用在具有虛擬電感電流漣波控制於固定頻率導通時間控制之降壓轉換器、具有本位適應性電壓定位設計於固定電流漣波導通時間控制之電壓調節器。本文提出快速動態響應電路之操作概念，主要使用高頻回授控制電路去濾出在負載暫態時下的輸出電壓，並進而快速動態改變其導通時間的寬度大小，所以其不只可以防止輸出電壓在輕載轉換成重載而快速下降，更能縮短輸出電壓在重載轉換成輕載之穩態時間。
經由實驗與模擬結果之驗證，本論文提出應用於快速動態響應降壓轉換器之適應性導通時間控制電路，除了有效降低輸出電容的成本與大小之外，更可以改善負載暫態響應。

This dissertation presents and studies the adaptive on-time control circuits for buck converter with quick dynamic response. The adaptive on-time control circuits for buck converter are widely used for the improvement of light-load efficiency because it can reduce switching loss at light load condition. In recent years, switching power supply requirement has the trend of fast transient response, because it can improve load transient response to reduce output capacitance, especially to central processing unit (CPU) and high current slew rate load applications. The main contributions of the dissertation are the development and analysis of the quick dynamic response of the ripple-based constant frequency on-time control circuit with virtual inductor current ripple for buck converter, the constant frequency on-time control circuit for buck converter, and constant current ripple on-time control circuit with native adaptive voltage positioning (AVP) design for voltage regulators (VRs). The concept of operation uses the high frequency feedback control to filter VOUT at the load transient and change the on-time width dynamically. It not only prevents VOUT from dropping significantly at the droop, but also reduces the settling time at the load transient compared to the control without quick response.
Both experimental and simulation results confirm that the proposed adaptive on-time control circuits for buck converter with quick dynamic response can reduce the cost and size of the output capacitance and improve load transient response.

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