近年隨著物聯網(Internet of Things, IoT)和獵能技術(Energy Harvesting)的發展，穿戴式裝置或無線傳感晶片之供電端通常為能夠獵取環境中能量的獵能器，而這些獵能器的輸出電壓通常都偏低，所以本研究提出具全積體化低電壓啟動電路的升壓型直流-直流轉換器，所提出的啟動機制並不需要經過後製程調校或額外外部元件、能量源，是一利於整合的SoC升壓型轉換器晶片。另外，考量到應用端為輕載，所以選用脈波頻率調變(Pulse-Frequency-Modulation, PFM)的控制方法來實現轉換器之控制器設計，使輕載時能有較好的效率表現。

本晶片使用台灣積體電路公司(TSMC)提供之0.18μm 1P6M Mixed-signal Standard CMOS製程實現之，而晶片面積為720μm × 735μm，並採用DIP 24S/B進行封裝。根據量測結果，本晶片最低啟動電壓為82mV，成功啟動後輸出電壓可穩在1V - 1.8V，而最佳效率為78.55%。另外，亦實際使用熱電溫差發電片當作輸入能量源進行量測，藉由人體體溫和室溫之間的溫差而轉換出的電壓，便能使本研究之系統成功啟動，穩定提供輸出電壓供應用端使用。

The most critical issue of using energy harvesters is their low output voltage, which makes it difficult to power up traditional electronic circuits. Therefore, this thesis proposes a fully-integrated inductor-based dc-dc boost converter with low startup voltage for thermoelectric harvester. In the initial state, low-voltage ring oscillator built by low supply voltage logic, charge pump and voltage-triggered pulse generator are used to charge the output capacitor and increase the output voltage (VOUT). When VOUT is high enough, the system will enter the open-loop state. When VOUT is increased to exceed another predefined voltage, the system will operate in the closed-loop state and VOUT will be regulated at 1.8V finally. It is worth mentioning that the startup technique in the proposed chip does not need to use any post-fabrication process, secondary energy source, or extra off-chip components.

The proposed chip was fabricated by TSMC 0.18μm 1P6M mixed-signal standard CMOS process, and chip area is 720×735μm2. According to measurement results, the minimal startup voltage of the converter is as low as 82mV, and VOUT can be regulated between 1 V and 1.8 V. Moreover, the measured peak efficiency achieves 78.55%.

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