本篇論文提出一能操作在接近電晶體臨界電壓的極低輸入電壓下，並能在此低電壓下正常啟動之升壓型直流-直流轉換器。系統的啟動分為三個階段， 分別為起始延遲導通階段、開迴路啟動階段，以及閉迴路控制階段。在系統開始啟動時，利用起始延遲導通階段、以及使用環式震盪器控制的開迴路啟動階段，將輸出電壓升至足以驅動所有電路的電壓(2.5 V)以後，最後進入閉迴路的脈波頻率調變(PFM)控制。
此晶片使用台灣積體電路公司0.35 μm 2P4M 3.3 V混合訊號製程，以32 S/B封裝，尺寸為1.125 × 2.14 mm2。設計規格輸入電壓範圍為0.7 V至3.2 V，輸出電壓為3.3 V，負載電流範圍為空載至200 mA。量測結果證明晶片可由1 V啟動，系統最大負載範圍為空載至200 mA，最高轉換效率約為74%。

A boost DC-DC converter with a wide input voltage range and low start-up voltage is proposed in this thesis. The proposed converter is capable to startup successfully and operates correctly with a low input voltage. The start-up procedure is divided into three states - initial, open-loop, and closed-loop states. The output voltage can be boosted to 2.5 V, which is enough to drive most of the analog and digital circuits, during the initial state and the open-loop state. Then, the system enters the closed-loop state. The switching signals of the power switches are provided by ring oscillators during the open-loop state, and by the PFM modulator during the closed-loop state.
The die area of this chip is 1.125 x 2.14 mm2, and it was fabricated by using Taiwan Semiconductor Manufacturing Company (TSMC) 0.35 μm 2P4M 3.3 V mixed-signal polycide process. The input voltage of the converter ranges from 0.7 V to 3.2 V, and the output voltage is set to 3.3 V. According to the measurement results, the proposed system can be successfully powered up with a 1-V input voltage. The load current of the converter may range from zero to 200 mA, and the maximum conversion efficiency is around 74%.

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