隨著科技發展快速可攜式電子產品已隨處可見。在這些電子產品中電源管理IC為其重要的一部分，其能為電子產品裡各個子系統提供一穩定的電源使其正常運作。如今電源轉換器正朝著更小的佔位面積與更高的轉換效率方向前進，以達到節能的目的。本篇論文提出「使用漣波控制主動箝位降壓式轉換器」，利用主動箝位電路產生一負電流來達成零電壓切換，進一步提升轉換器效率。在開關控制方面使用有別於以往的非互補控制方法，相較於傳統互補控制方法，能在進一步降低轉換器損耗。回授控制採用漣波控制中的自適應關閉時間控制，當輸入電壓、輸出電壓、負載電流改變時，也能維持相同的切換頻率，降低切換式電源的 EMI 問題。在暫態響應方面也較一般的電壓控制模式或是電流控制模式快速。本文採用 TSMC 0.18μm 1P6T18HVG2 製程實現。晶片面積為2.555 × 1.881 mm2。功率級輸入電壓為12 V，輸出電壓為3.3 V，切換頻率為500 kHz，輸出負載電流範圍為200 mA至800 mA。諧振電感與箝位電容分別為1 μH及150 nF，輸出電感與輸出電容分別為27 μH及20 μF。

With the rapid development of technology, portable electronic products have become ubiquitous. Power management ICs are an important part of these electronic products, providing stable power to various subsystems for their proper operation. Power converters are now moving towards smaller area and higher conversion efficiency to achieve energy savings.
This paper introduces the " Active-Clamp Buck Converter with Ripple Based Control". It uses an active clamp circuit to generate negative current for achieving zero-voltage switching, thereby enhancing the converter's efficiency. Unlike traditional complementary control method, a noncomplementary control method is employed for switch control, which helps reduce losses in the converter. The feedback control uses ripple-based adaptive off time control, enabling the converter to maintain the same
switching frequency even when there are changes in input voltage, output voltage, and load current, thereby reducing EMI issues. Additionally, the proposed design exhibits faster transient response compared to conventional voltage mode control or current mode control. The paper is implemented by TSMC 0.18μm 1P6M T18HVG2 process. The size of chip is 2.555 × 1.881 mm². The input voltage is 12 V, output voltage is 3.3 V and switching frequency is 500 kHz. The output load range is 200 mA to 800 mA. The resonant inductor and clamp capacitor are 1 μH and 150 nF. The output inductor and output capacitor are 27 μH and 20 μF.

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