本論文提出一新穎供獵能器使用之低漣波雙導通時間降壓電路。本文針對切換式降壓穩壓電路之固定導通時間(Constant-On-Time, COT)控制技術進行探討與模擬實作。傳統之固定導通時間控制技術存有潛在的效率與漣波權衡限制，因而本論文提出「雙導通時間控制」（Dual On-Time）技術。利用兩個不同導通時間控制，可提供設計者在簡單之架構下，藉優化過程設計出最佳的導通時間，在極輕負載下同時實現低漣波且維持高效率的降壓穩壓電路。
本文中所模擬的雙導通時間控制電路工作電壓範圍為2.2 V ~ 3.3 V，負載電流範圍為0.5 mA ~ 2 mA，最大模擬轉換效率為94.6%；輸出電壓為1.3 V，輸出漣波< 30 mV，在負載電流為0.05 mA時，模擬轉換效率仍有80%以上；適合於獵能技術之應用。

In this thesis, a novel low-ripple dual on-time (DOT) buck circuit for energy harvesters. Constant on-time (Constant-On-Time, COT)-typed control technologies for buck switching regulator circuits is investigated, simulated, and implemented. There are potential tradeoff limitations between efficiency and ripple for traditional constant on-time control technologies, so this thesis presents a 'Dual On-Time' (DOT) technology. By using two different on-time periods, the designer can achieve high efficiency buck regulator circuit while maintaining low ripple in an ultra-light load after optimization based on the simple architecture.
The proposed DOT control circuit is operated at the voltage ranging from 2.2 V to 3.3 V in simulation. The load current ranges from 0.5 mA to 2 mA. The maximum conversion efficiency is achieved to 94.6%. The output voltage is 1.3 V, and the output ripple is less than 30 mV. At the load current of 0.05 mA, simulated conversion efficiency remains more than 80%, so the proposed DOT circuit is suitable for energy harvesting technologies.

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