本論文的電荷泵系統運用了兩種不同架構的電荷泵，使整個系統能在低輸入電壓下運作，並擁有較低的開關導通電阻，此外，頻率回授控制的機制，讓輸出電壓能夠在負載變動的情況下維持穩定。
一般的電荷泵都是在標準電壓1.8 V下運作，若是輸入電壓下降，受臨界電壓的限制，電荷泵的開關便會處於弱導通的狀態，因此傳統電荷泵在低輸入電壓的情況下很難順利升壓。為解決此問題，本論文提出的低壓電荷泵利用不同的偏壓方式加強了開關的導通程度，使電荷泵能夠在低操作電壓下順利升壓。
除此之外，過去文獻中的電荷泵還存在時脈重疊時有逆流電流，以及開關導通電阻會在電荷傳輸過程中變大等問題。本論文中的高壓電荷泵透過輔助開關與控制時脈的設計解決了上述問題，同時提升了驅動能力和能量效率。
晶片使用TSMC 0.18 μm 1P6M CMOS的製程來製作，尺寸大小為963 μm x 1213 μm。電路的供應電壓為0.56 V、負載電容為10 pF，在負載電流0 μA到 31 μA的條件下，可以達到輸出電壓3.1 V之規格。

This thesis proposes a new charge pump system for low input voltage with low switch on-resistance by utilizing two different charge pump structures in the system. In addition, the frequency feedback control mechanism is used to stabilize the output voltage when the output loading changes.
Usual charge pumps are operated under standard voltage of 1.8 V. If the input voltage drops, the significant threshold voltage of transistors will cause the switches of the charge pump to weakly turn on. Thus, traditional charge pumps are difficult to boost voltage if the input voltage is low. To solve this problem, this thesis proposes a low-voltage charge pump with different biasing method which helps switches to turn on, so that the charge pump can boost voltage successfully under low operating voltage.
Besides, there are some problems in previous charge pumps, such as the reverse current when clocks overlap and the increasing switch on-resistance when the charges are being transferred. In the high-voltage charge pump demonstrated in this thesis, the design of auxiliary switches and control clock not only solves above problems but also improves driving capability and power efficiency.
The chip was fabricated in the TSMC 0.18μm 1P6M CMOS process and its size is 963 μm x 1213 μm. The supply voltage of the circuit is 0.56 V and an output voltage of 3.1 V is achieved when the load capacitance is 10 pF and the load current ranges from 0 μA to 31 μA.

[1] F. Pan and T. Samaddar, Charge Pump Circuit Design, McGraw-Hill, 2006.
[2] J.D. Cockcroft and E.T. Walton, “Production of high velocity positive ions”, Proceedings of the Royal Society, A, vol. 136, pp. 619-630, 1932.
[3] J.F. Dickson, “On-chip high-voltage generation in MNOS integrated circuits using an improved voltage multiplier technique”, IEEE Journal of Solid-State Circuits, vol. 11, no. 3, pp. 374-378, Jun. 1976.
[4] J. Shin, I.-Y. Chung, Y. J. Park, and H. S. Min, “A new charge pump without degradation in threshold voltage due to body effect”, IEEE J. Solid-State Circuits, vol. 35, no. 8, pp. 1227-1230, Aug. 2000.
[5] L. Mensi, L. Colalongo, A. Richelli, and Z. M. Kovacs-Vajna, “A new integrated charge pump architecture using dynamic biasing of pass transistors”, Proceedings of the 31st European Solid-State Circuits Conference, pp. 85–88, Sep. 2005.
[6] M.-D. Ker, S.-L. Chen and C.-S. Tsai, “Design of charge pump circuit with consideration of gate-oxide reliability in low-voltage CMOS processes”, IEEE Journal of Solid-State Circuits, vol. 41, no. 5, pp. 1100-1107, May 2006.
[7] Y.-H. Weng, H.-W. Tsai and M.-D. Ker, “Design to suppress return-back leakage current of charge pump circuit in low-voltage CMOS process”, Microelectronics Reliability, vol. 51, no. 5, pp. 871-878, May 2011.
[8] H. Peng, N. Tang, Y. Yang and D. Heo, “CMOS startup charge pump with body bias and backward control for energy harvesting step-up converters”, IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 61, no. 6, pp. 1618-1628, Jun. 2014.
[9] 楊毓群, “具有零逆回流電流、恆定開關導通電阻和頻率調整控制的電荷泵”, 國立清華大學, 電子工程研究所, 碩士論文, 中華民國一百零三年七月.
[10] J.-Y. Lee, S.-E. Kim, S.-J. Song, J.-K. Kim, S. Kim and H.-J. Yoo, “A regulated charge pump with small ripple voltage and fast start-up”, IEEE Journal of Solid-State Circuits, vol. 41, no. 2, pp. 425-432, Feb. 2006.
[11] C.-H. Wu and C.-L. Chen, “A low-ripple charge pump with continuous pumping current control”, 2008 51st Midwest Symposium on Circuits and Systems (MWSCAS), 2008.
[12] M. Chen, X. Wu and M. Zhao, “Novel high efficiency low ripple charge pump using variable frequency modulation”, 2010 International Conference on Microelectronics (ICM), 2010.
[13] 陳冠嘉, “具有低輸入電壓、零逆回流電流、恆定開關導通電阻和頻率調整控制的電荷泵”, 國立清華大學, 電子工程研究所, 碩士論文, 中華民國一百一十年一月.
[14] B. Razavi, Design of Analog CMOS Integrated Circuits, McGraw-Hill, 2001.
[15] C. Zhang, M.-C. Lin, and M. Syrzycki, “Process variation compensated voltage controlled ring oscillator with subtraction-based voltage controlled current source”, 2011 24th Canadian Conference on Electrical and Computer Engineering (CCECE), 2011.
[16] W. Jung, S. Oh, S. Bang, Y. Lee, Z. Foo, G. Kim, Y. Zhang, D. Sylvester and D. Blaauw, “An ultra-low power fully integrated energy harvester based on self-oscillating switched-capacitor voltage doubler’’, IEEE Journal of Solid-State Circuits, vol. 49, no. 12, pp. 2800-2811, Dec. 2014.
[17] B. Mohammadi and J. Rodrigues, “Ultra low energy and area efficient charge pump with automatic clock controller in 65 nm CMOS’’, 2015 IEEE Asian Solid-State Circuits Conference (A-SSCC), pp. 1-4, 2015.
[18] A. Mahmoud, M. Alhawari, B. Mohammad, H. Saleh and M. Ismail, “A gain-controlled, low-leakage Dickson charge pump for energy-harvesting applications’’, IEEE Transactions on Very Large Scale Integration (VLSI) Systems, vol. 27, no. 5, pp. 1114-1123, May 2019.