近年來，在全球暖化、氣候變遷的影響下，綠能意識逐漸抬頭，將環境中能源轉換成電能供電的獵能成了一個熱門的議題。但獵能器所能產生的電壓往往較低，無法直接供電給一般的儀器使用，因此本研究提出一個低電壓啟動的升壓直流-直流轉換器，且啟動機制不需額外外接元件與後製程調校，利於整合於SoC晶片中。另外，此轉換器具寬輸入範圍，將不受限於一種獵能器的應用。而考量到應用範圍多為輕載，本研究以脈波頻率調變(Pulse Frequency Modulation, PFM)方法控制轉換器，並將轉換器操作於不連續導通模式(Discontinuous Conduction Mode, DCM)，以提升系統的效率表現。
本晶片使用台灣積體電路公司(TSMC)所提供的90nm 1P9M Mixed-signal Standard CMOS製程實現，晶片面積為705.85μm×852.7μm。根據模擬結果，最低啟動電壓為60mV，而系統輸入電壓範圍為0.06-0.9V，系統輸出電壓經升壓後將穩於1V，且系統最高效率為88.38%。

Energy harvesting has become a hot research topic due to the rise of Internet of Things (IoT) and the growing damage of global warming. However, at the low voltage provided by the energy harvesters, traditional devices are unable to work properly. Therefore, in this thesis, a boost dc-dc converter with low-startup voltage is proposed. Without additional off-chip components and post-fabrication trimming, the converter is suitable to be integrated in SoC chips. In order to cope with several type of harvesting energy sources, the converter is designed to have a wide input voltage range. Besides, considering the light load situation, the proposed converter is controlled by pulse frequency modulation (PFM) method and is operating at the discontinuous conduction mode (DCM) for better efficiency.

The proposed chip is fabricated by TSMC 90nm 1P9M Mixed-signal Standard CMOS process, with a chip area of 705.85μm×852.7μm. According to the simulation results, the proposed converter has a minimum startup voltage of 60mV. The input voltage range of the converter is 0.06-0.9V, and the output voltage is boosted and stabilize at 1V. Furthermore, the peak efficiency is 88.38%.

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