本論文提出一寬輸入電壓範圍及脈波頻率調變(Pulse Frequency Modulation, PFM)控制的升-降壓單電感雙輸出電壓轉換器。為了能延長單次充電後的電池使用時間，本電壓轉換器採用了升-降壓架構來提升可攜式電子產品的連續使用時間；另外，本電路採用了全比較器回授控制技術，利用比較器取代運算放大器去偵測輸出電壓狀態，所以系統具有快速暫態響之優點，且無穩定性問題及不需要額外的迴路補償元件(電阻或電容)，也因此可以減少晶片及印刷電路板(Printed circuit board, PCB)尺寸，進而讓成本降低且更適合於System on chip (SoC)應用。先前文獻所使用的脈波寬度調變(Pulse Width Modulation, PWM) 控制技術會有輕載效率不佳之問題，所以本電壓轉換器採用了脈波頻率調變控制技術來提升輕載時之效率，因此本電壓轉換器更適用於輕載應用，例如生醫感測電路；另外，本轉換器具有兩個不同的輸出電壓準位，可作為不同製程應用的電源來源，所以本電壓轉換器也適用於System in package (SiP)。
本晶片使用台灣積體電路公司0.35-μm 2P4M 5V混合訊號製程，尺寸為2.3×1.9 mm2。此晶片的輸入電壓範圍為1.8 – 5 V，兩個輸出電壓分別為1.8 V及3.3 V，其最大輸出電流分別為40 mA及30 mA，負載調節率(Load regulation)分別為0.048 mV/mA 及0.132 mV/mA，而互穩壓調節率(Cross regulation)則分別為0.034 mV/mA及0.009 mV/mA。

An integrated pulse-frequency-modulation (PFM) controlled buck-boost single-inductor dual-output (SIDO) DC-DC converter with wide supply voltage range is presented. The converter adopts the buck-boost power stage architecture to prolong the operation time of the portable devices. In addition, the all-comparator feedback control technique is used, which means that error amplifiers are replaced by comparators to detect the state of outputs. By using this technique, the converter can achieve fast transient response, and has no stability problem. Moreover, no external compensation components are needed. Therefore, the sizes of chip and its printed circuit board (PCB) can be reduced, the cost can be decreased, and, hence, it is suitable for system-on-chip (SoC) applications. Compared with converters using pulse width modulation (PWM) control, the proposed PFM–controlled converter achieves better efficiency at light load. Hence, this converter can be used for light-load applications (e.g., biomedical sensor chip). Moreover, there are two different output voltages in the proposed chip, and they can be used to power two chips manufactured with different processes or two sub-systems with different supply voltages. Thus, the converter is also suitable for system in package (SiP).
The proposed converter chip was fabricated by TSMC 0.35-μm CMOS process, and the area of the chip is 2.3×1.9 mm2. The input voltage range of this converter is 1.8 – 5 V, its two output voltages are 1.8 V and 3.3 V, and their maximal output currents are 30 mA and 40 mA. The load-regulations of these two outputs are 0.048 mV/mA and 0.132 mV/mA, and the cross-regulations are 0.034 mV/mA and 0.009 mV/mA.

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