本論文整合電阻式感測讀取電路及逐漸趨近式類比數位轉換器的電路架構，可偵測極小電阻變化，並透過前述電路轉換為數位訊號做後續數據分析。本系統架構前端為電阻式感測器讀取電路，可偵測的電阻變化範圍為50-kΩ，並配備校準功能可抗溫度、濕度等環境因子，使系統可操作在非理想環境下。本系統架構後端為逐漸趨近式類比數位轉換器，具備二項優點。第一項為採用串連式電容陣列設計，可有效降低寄生電容影響，取得高精度轉換率。第二項為採用改良式全差動分段式架構，透過全差動方式，可有效降低雜訊；透過分段式架構將最高位及最低位電容陣列以耦合電容串聯，可有效降低布局面積；透過改良式架構使用單位電容做為耦合電容，可避免電容不匹配問題。本設計使用台積電 0.18-µm CMOS製程來實作晶片，晶片面積為933 × 980-μm2，操作電壓為1.8伏特及取樣速度為每秒一千四百萬次，總消耗功率為3.7-μW，有效位元數為8bits。

This paper integrates the resistive readout circuit with an analog-to-digital converter circuit. These combined circuits can detect very small changes in resistance and convert such changes into digital signals for subsequent data analysis. The front end of the combination circuits is a resistive readout circuit with a detectable resistance range of 50-kΩ that is equipped with a calibration mode to resist environmental factors such as temperature and humidity. Therefore, the system can work in a non-ideal environment. The back end of the combination circuits is a successive approximation analog-to-digital converter (A-D-C) circuit. The ADC circuit has two advantages: The first advantage is the use of a series capacitor array design that effectively reduces the influence of parasitic capacitance and reduces the layout area. The second advantage is the use of an improved fully differential segmented structure that effectively reduces noise. In addition, by using a unit capacitor as a coupling capacitor, the problem of capacitor mismatch can be avoided. The full circuit design utilizes TSMC’s 0.18-µm CMOS process to implement the chip, for which the chip area is 933 × 980-μm2. The operating voltage of this chip is 1.8 volts, and the operating speed reaches 14 million samples per second. The total power consumption is 3.7-µW, and the effective number of bits is 8 bits.

[1] K. Park, S. Choi, H. Y. Chae, C.S. Park, S. Lee, Y. Lim, H. Shin, J. J. Kim, "An Energy-Efficient Multimode Multichannel Gas-Sensor System with Learning-Based Optimization and Self-Calibration Schemes," IEEE Transactions on Industrial Electronics, vol. 67, no. 3, pp. 2402-2410, March 2020, doi: 10.1109/TIE.2019.2905819.
[2] K. Kliche, G. Kattinger, S. Billat, L. Shen, S. Messner and R. Zengerle, "Sensor for Thermal Gas Analysis Based on Micromachined Silicon-Microwires," IEEE Sensors Journal, vol. 13, no. 7, pp. 2626-2635, July 2013, doi: 10.1109/JSEN.2013.2252008.
[3] R. H. Walden, "Analog-to-digital converter survey and analysis," IEEE Journal on Selected Areas in Communications, vol. 17, no. 4, pp. 539-550, April 1999, doi: 10.1109/49.761034.
[4] H. Ha, Y. Suh, S. Lee, H. Park and J. Sim, "A 0.5V, 11.3-μW, 1-kS/s resistive sensor interface circuit with correlated double sampling," Proceedings of the IEEE 2012 Custom Integrated Circuits Conference, 2012, pp. 1-4, doi: 10.1109/CICC.2012.6330702.
[5] K. Kliche, S. Billat, F. Hedrich, C. Ziegler and R. Zengerle, "Sensor for gas analysis based on thermal conductivity, specific heat capacity and thermal diffusivity," 2011 IEEE 24th International Conference on Micro Electro Mechanical Systems, 2011, pp. 1189-1192, doi: 10.1109/MEMSYS.2011.5734644.
[6] Z. Cai, van Veldhoven, Robert H. M., A. Falepin, H. Suy, E. Sterckx,C. Bitterlich, Makinwa, Kofi A. A., Pertijs, Michiel A. P., "A Ratiometric Readout Circuit for Thermal-Conductivity-Based Resistive CO2 Sensors," IEEE Journal of Solid-State Circuits, vol. 51, no. 10, pp. 2463-2474, Oct. 2016, doi: 10.1109/JSSC.2016.2587861.
[7] M. Choi, J. Gu, D. Blaauw and D. Sylvester, "Wide input range 1.7μW 1.2kS/s resistive sensor interface circuit with 1 cycle/sample logarithmic sub-ranging," 2015 Symposium on VLSI Circuits (VLSI Circuits), 2015, pp. C330-C331, doi: 10.1109/VLSIC.2015.7231311.
[8] H. Attia, S. Gaya, A. Alamoudi, M. Alshehri, Fahad, Al-Suhaimi, Abdulrahman, N. Alsulaim, A. M. Al Naser, and J. E. M. Aghyad, A. M. Alqahtani, J. Prieto Rojas, S. Al-Dharrab, F. Al-Dirini, "Wireless Geophone Sensing System for Real-Time Seismic Data Acquisition," IEEE Access, vol. 8, pp. 81116-81128, 2020, doi: 10.1109/ACCESS.2020.2989280.
[9] S. Sutula, C. Ferrer and F. Serra-Graells, "A 400 $mu$ W Hz-Range Lock-In A/D Frontend Channel for Infrared Spectroscopic Gas Recognition," IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 58, no. 7, pp. 1561-1568, July 2011, doi: 10.1109/TCSI.2011.2142770.
[10] S. W. Chiu, J. H. Wang, K. H. Chang, T. H. Chang, C. M. Wang, C. L. Chang, C. T. Tang, C. F. Chen, C. H. Shih, H. W. Kuo, L. C. Wang, H. Chen, C. C. Hsieh, M. F. Chang, Y. W. Liu, T. J. Chen, C. H. Yang, H. Chiueh, J. M. Shyu, K. T. Tang, "A Fully Integrated Nose-on-a-Chip for Rapid Diagnosis of Ventilator-Associated Pneumonia," IEEE Transactions on Biomedical Circuits and Systems, vol. 8, no. 6, pp. 765-778, Dec. 2014, doi: 10.1109/TBCAS.2014.2377754.
[11] Li H, Boling CS, Mason AJ. CMOS Amperometric ADC With High Sensitivity, Dynamic Range and Power Efficiency for Air Quality Monitoring. IEEE Trans Biomed Circuits Syst. 2016 Aug;10(4):817-27. doi: 10.1109/TBCAS.2016.2571306. Epub 2016 Jun 23. PMID: 27352395; PMCID: PMC5056750.
[12] N. Delorme, C. Le Blanc, A. Dezzani, M. Bély, A. Ferret, S. Laminette, J. Roudier, E. Colinet, "A NEMS-Array Control IC for Subattogram Mass Sensing Applications in 28 nm CMOS Technology," IEEE Journal of Solid-State Circuits, vol. 51, no. 1, pp. 249-258, Jan. 2016, doi: 10.1109/JSSC.2015.2492782.
[13] B. Murmann, "ADC Performance Survey 1997-2021," [Online]. Available: http://web.stanford.edu/~murmann/adcsurvey.html.
[14] Y. Chen, X. Zhu, H. Tamura, M. Kibune, Y. Tomita, T. Hamada, M. Yoshioka, K. Ishikawa, T. Takayama, J. Ogawa, S. Tsukamoto, T. Kuroda, "Split capacitor DAC mismatch calibration in successive approximation ADC," 2009 IEEE Custom Integrated Circuits Conference, 2009, pp. 279-282, doi: 10.1109/CICC.2009.5280859.
[15] W. Mao, Y. Li, C. Heng and Y. Lian, "A Low Power 12-bit 1-kS/s SAR ADC for Biomedical Signal Processing," IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 66, no. 2, pp. 477-488, Feb. 2019, doi: 10.1109/TCSI.2018.2859837.
[16] S. Xie and A. Theuwissen, "A 10 Bit 5 MS/s Column SAR ADC With Digital Error Correction for CMOS Image Sensors," IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 67, no. 6, pp. 984-988, June 2020, doi: 10.1109/TCSII.2019.2928204.
[17] Sergio Franco. 2001. Design with Operational Amplifiers and Analog Integrated Circuits (3rd. ed.). McGraw-Hill, Inc., USA.
[18] B. Razavi, Design of Analog CMOS Integrated Circuits. Boston, MA: McGraw-Hill, 2001.
[19] T. B. Cho and P. R. Gray, "A 10 b, 20 M sample/s, 35 mW pipeline A/D converter," IEEE Journal of Solid-State Circuits, vol. 30, no. 3, pp. 166-172, March 1995, doi: 10.1109/4.364429.
[20] R. Gray, "Oversampled Sigma-Delta Modulation," IEEE Transactions on Communications, vol. 35, no. 5, pp. 481-489, May 1987, doi: 10.1109/TCOM.1987.1096814.
[21] S. S. Ghoreishizadeh, C. Baj-Rossi, A. Cavallini, S. Carrara and G. De Micheli, "An Integrated Control and Readout Circuit for Implantable Multi-Target Electrochemical Biosensing," IEEE Transactions on Biomedical Circuits and Systems, vol. 8, no. 6, pp. 891-898, Dec. 2014, doi: 10.1109/TBCAS.2014.2315157.
[22] J. L. McCreary and P. R. Gray, "All-MOS charge redistribution analog-to-digital conversion techniques. I," IEEE Journal of Solid-State Circuits, vol. 10, no. 6, pp. 371-379, Dec. 1975, doi: 10.1109/JSSC.1975.1050629.
[23] T. Kobayashi, K. Nogami, T. Shirotori and Y. Fujimoto, "A current-controlled latch sense amplifier and a static power-saving input buffer for low-power architecture," IEEE Journal of Solid-State Circuits, vol. 28, no. 4, pp. 523-527, April 1993, doi: 10.1109/4.210039.