本論文提出一種應用於光獵能系統之單電感升降壓轉換器，以CMOS太陽能電池做為輸入來源，經電源管理單元，為感測器、類比至數位轉換器等後端電路提供穩定的電源。由於 CMOS太陽能電池供應能量極低，使用傳統轉換器架構無法針對不同負載做最佳化。為了解決輕載轉換效率低落的問題並同時提升重載轉換效率，本論文使用一新型轉換器架構，得以將輕載與重載能量傳輸路徑分離以個別最佳化，降低開關損耗，同時在重載模式下，控制電路偵測到太陽能電池達到最大功率點時，將超級電容與太陽能電池以串聯的形式供電，使單周期供應能量提高；而在太陽能電池尚未達到最大功率點時，持續以超級電容輔助供電。
本論文下線晶片使用 TSMC 0.18μm CMOS標準製程實現，整體晶片佈局面積含 I/O pads為1.356mm2，CMOS太陽能電池輸入電壓為 0V~0.55V，輸出電壓為 1V，負載電流範圍坐落於 0.001 mA ~1mA，其中在負載電流為 1mA(重載)情況下，可達最高能量轉換效率 95.26%，並於 0.001mA(輕載)情況下，最高轉換效率可達 89.32%。

This thesis presented a single inductor buck-boost converter applied to harvest light energy through CMOS solar cell and provide steady power for the back-end circuits, such as sensor, ADC and other circuits through the power management unit. Due to the extremely low energy supplied by CMOS solar cell, the traditional converter architecture cannot be optimized under different load conditions. In order to enhance the light and heavy load conversion efficiencies simultaneously, a novel converter architecture is adopted to this thesis to separate the light load and heavy load transmission paths and individually optimize the switching loss. Under heavy load, the super capacitor and solar cell are connected in series to boost up the single cycle supply energy when the solar cell reaches maximum power point(MPP). When the solar cell has not yet reached the MPP, the super capacitor supplies power to the load to help stabilize the output voltage.
The propose circuit is fabricated in a TSMC 0.18μm 1P6M CMOS process with a chip area of 1.356mm2 including I/O Pads. The input voltage of the CMOS solar cell is 0V~0.55V. The output voltage is 1V and the load current range is 0.001mA~1mA. The maximum conversion efficiency reaches 95.26% when the load current is 1mA (heavy load) and the conversion efficiency is 89.32% when the load current is 0.001mA(light load).

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