為了使呼吸感測系統具可攜性，並實現鋰電池供電，輸入電壓範圍3.4 V–4.2 V，本論文將線性穩壓器、微機電感測器、讀取電路與振幅數位轉換電路整合在一個晶片內，並將10位元數位輸出透過DAQ讀入電腦，由LabVIEW運算且即時顯示呼氣波型、振幅和頻率等資訊，本晶片實現無外部電容與分壓電阻之低壓降線性穩壓器，產生穩定電壓3.3 V給負載使用。本系統內建二組微懸臂樑感測器，一組更改架構，以增加其靈敏度，另一組沿用上一版本，以上是第一顆晶片的電路。第二顆晶片為一個低電壓與低功耗之參考電壓產生器，設計給低壓啟動或獵能升壓型轉換器使用。
第一顆晶片採用台積電 (TSMC) 0.35 μm CMOS/MEMS 2P4M 3.3 V 混合訊號製程加上微機電後製程製作，以48 S/B 封裝，尺寸為1.910×2.369 mm2，含一組感測器且供應電壓為3.6 V的系統功耗為3.15 mW。第二顆晶片採用台積電 0.18 μm 1P6M 混合訊號製程，以18 S/B 封裝，尺寸為0.473×0.314 mm2，隨著電源範圍0.4–1.8 V，總功耗47.6–403.2nW。

Three low drop-out linear regulators (LDOs) were designed for a battery-powered home-care respiration detection chip, which has been implemented in Taiwan Semiconductor Manufacturing Company (TSMC) 0.35 μm CMOS/MEMS 2P4M 3.3 V/5 V process. .These three LDOs supply power to sensor, analog, and digital blocks of the respiration detection chip, and all of them feature no external capacitor and resistor. Moreover, sensor sensitivity is improved by using wide cantilever. The measurement results show the chip works correctly.
The work mentioned above is the first chip. The second chip is to design a low-voltage low-power voltage reference circuit for converters with low startup voltage and energy harvesting circuit. This chip was designed by using TSMC 0.18 μm 1P6M mixed signal process. The post-layout simulations show that the lowest supply voltage is 0.4 V and its power consumption is 47.6 nW.

[1]M. K. Tsai, “Design of a Respiration Detection Chip with DC Offset Calibration Technique,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Nov. 2014.
[2]J. G. Webster, “Measurements of the Respiratory System,” Medical Instrumentation： Application and Design. New York: Wiley, 1998, ch. 9.
[3]C. Enz and G. C. Temes, “Circuit techniques for reducing the effects of op-amp imperfections: autozeroing, correlated double sampling, and chopper stabilization,” in Proc. IEEE, vol. 84, no. 11, Nov. 1996, pp.1584–1614.
[4]Q. Fan, F. Sebastiano, J. H. Huijsing, and K. A. A. Makinwa, “A 2.1 μW area-efficient capacitively-coupled chopper instrumentation amplifier for ECG applications in 65 nm CMOS,” in IEEE ASSCC, Nov. 2010, pp. 1–4.
[5]T. Cho, “Low-power, low-voltage, analog-to-digital converter technique using pipelined architectures,” Ph.D. Thesis, University of California, Berkeley, 1995.
[6]K. Nagaraj, “A parasitic-insensitive area-efficient approach to realizing very large time constants in switched-capacitor circuits,” IEEE Trans. Circuits Syst., vol. 36, no. 9, pp. 1210–1216, Sep. 1989.
[7]Y. W. Wang, “A wide-range programmable sinusoidal frequency synthesizer for electrochemical impedance spectroscopy measurement system,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jul. 2012.
[8]R. J. Baker, “Clocked Circuits,” in CMOS Circuit Design, Layout, and Simulation, 2nd edition, New York: Wiley, 2008, pp. 386–388.
[9]W. J. Wu, “Design of an impedance-to-digital converter for electrochemical impedance spectroscopic measurement system,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jun. 2013.
[10]蔡進譯，「超高效率太陽電池──從愛因斯坦的光電效應談起」，物理雙月刊，第三十七卷第五期，頁703，2005。
[11]D. Li, T. Li and D. Zhang, “A monolithic piezoresistive pressure-flow sensor with integrated signal-conditioning circuit,” IEEE Sensor J., vol. 11, no. 9, pp. 2122–2128, Sep. 2011.
[12]Y. C. Lin, “Design of a Temperature-Insensitive Micro Cantilever-Based Respiration Detection Chip,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jun. 2013.
[13]R. Y. Lin, “Design of a Respiration Detection Single Chip by Using Both Voltage- and Current-Mode MEMS Sensors,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jul. 2012.
[14]T. H. Liu, “Design of an Infant Respiration Detection System in a Single Chip by Use of a Micro-Cantilever Flow Sensor,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jul. 2011.
[15]I. Ta. Tseng, “Design of an Infant Respiration Detection Instrument by Use of a MEMS Piezo-Resistive Sensor,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jun. 2008.
[16]V. Gupta and G. A. Rincon-Mora, “Analysis and design of monolithic, high PSR, linear regulators for SoC applications,” in Proc. IEEE SOC Conf., pp.311–315, Santa Clara, California, 2004.
[17]R. J. Milliken, J. Silva-Martinez, and E. Sanchez-Sinencio, “Full on-chip CMOS low-dropout voltage regulator,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 54, no. 9, pp. 1879–1890, Sept 2007.
[18]C. Zhan and W. H. Ki, “An output-capacitor-free adaptively biased low-dropout regulator with subthreshold undershoot-reduction for SoC,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 59, no. 5, pp. 1119–1131, May 2012.
[19]G. Rincon-Mora and P. E. Allen, “A 1.1-V current-mode and piecewise-linear curvature-corrected bandgap reference,” IEEE J. Solid-State Circuits, vol. 33, no. 10, pp. 1551–1554, Oct. 1998.
[20]K. N. Leung and P. K. T. Mok, “A sub-1-V 15-ppm/℃ CMOS bandgap voltage reference without requiring low threshold voltage device,” IEEE J. Solid-State Circuits, vol. 37, pp. 526–530, April 2002.
[21]B. Razavi, Design of Analog CMOS Integrated Circuits, Chap 11. McGraw-Hill Education, 2002.
[22]H. Banba, et al., “A CMOS bandgap reference circuit with sub-1V operation,” IEEE J. Solid-State Circuits, vol.34, no. 5, pp. 670–674, May 1999.
[23]K. N. Leung and P. K. T. Mok, “A CMOS voltage reference based on weighted ∆VGS for CMOS low-dropout linear regulators,” IEEE J. Solid-State Circuits, vol. 38, pp. 146–150, Jan. 2003.
[24]G. De Vita and G. Iannaccone, “A Sub-1-V, 10 ppm/℃, nanopower voltage reference generator,” IEEE J. Solid-State Circuits, vol. 42, no. 7,pp. 1536–1542, Jul. 2007.
[25]Y. Wang, Z. Zhu, J. Yao, and Y. Yang, “A 0.45-V, 14.6-nW CMOS subthreshold voltage reference with no resistors and no BJTs.” IEEE Trans. Circuits Syst. II, Exp. Briefs, vol. 62, no. 7, pp. 621–625, Jul. 2015.
[26]L. Y. Chen, “Design of a Pulse-Frequency-Modulation Controlled DC-DC Boost Converter with Low-Startup Voltage and Wide-Input-Range,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Nov. 2015.
[27]D. L. Tsai, “A Low-Power-Consumption Boost Converter with Maximum Power Point Tracking Algorithm for Indoor Photovoltaic Energy Harvesting,” M.S. thesis, Dept. of Elect. Eng., National Cheng Kung Univ., Tainan, Taiwan, R.O.C., Jul. 2014.
[28]Wei-Chung Chen, Yi-Ping Su, Yu-Huei Lee, Chin-Long Wey, Ke-Horng Chen, “0.65V-Input-Voltage 0.6V-Output-Voltage 30ppm/℃ Low-Dropout Regulator with Embedded Voltage Reference for Low-Power Biomedical Systems,” ISSCC Dig. Tech. Papers, pp301–306, Feb. 2014.