有鑑於能源危機及環境汙染的問題日益嚴重，環境永續的觀念也逐漸受到重視，光能、熱能、動能等等綠色能源遂成為趨勢，而藉由環境中的能量(如太陽能、熱能與溫度差)並轉換成電能，稱之為獵能。本研究提出一個具有能量緩衝級與最大功率點追蹤電路的光能獵能器，確保太陽能電池能操作於其最大功率點，並且能妥善分配能量於負載端與能量緩衝級，當太陽能電池所提供之能量充足時，可將能量儲存於能量緩衝級，而在太陽能電池所提供之能量小於負載所需能量時，則可以使用儲存於能量緩衝級之能量作為輔助，提高供電之穩定度。另外，為了在低功率下能有好的轉換效率，轉換器操作於非連續導通模式(DCM)，控制方法使用脈波頻率調變(PFM)進行控制，並結合分時多工法(TMC)與能量分佈法(PDC)來分配負載端與能量緩衝級的能量。
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，晶片總面積為1.079 mm2，並採用DIP 40 S/B進行封裝。所測得之最佳追蹤效率為99.62%，太陽能電池的最佳轉換效率為95.77%，太陽能電池的最佳總效率為95.41%，太陽能電池與儲能端共同提供負載端的最佳轉換效率為95.48%。為了增加供應電源的穩定性，加入能量緩衝級輔助後，在最低光照(IPH=200μA)時系統最高可抽載至410μA，而在最高光照(IPH=3mA)時系統最高可抽載至3.8mA。

In this thesis, a boost dc-dc converter for photovoltaic (PV) energy harvester with energy buffer stage and maximum power point tracking (MPPT) circuit is proposed. A perturb and observe method (P&O) is used to track the maximum power point of the PV cell. The control method combining time-multiplexing control (TMC) and power-distributive control (PDC) is used to control single-inductor dual-input dual output (SIDIDO) system, properly distributing energy form harvester, storage and output.

The proposed chip was fabricated by TSMC 0.18μm 1P6M mixed-signal standard CMOS process, and the chip area is 1.079 mm2. According to measurement results, the peak tracking efficiency is 99.62 %, the peak conversion efficiency for input source to output is 95.77%, the peak total efficiency for input source to output is 95.41%, and the peak conversion efficiency for input source and energy buffer stage to output is 95.48%. Adding the energy buffer stage, the maximum load current for IPH=0.2mA is 410μA, and the maximum load current for IPH=3.0mA is 3.8mA.

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