本論文利用微分電路取得電容電流漣波及近似最佳時間控制技術實現定頻磁滯型降壓穩壓器，架構採用電流模式磁滯控制。為了減少依賴輸出電容之寄生電阻以及降低偵測電流資訊時的耗能，本研究採用微分電路感測輸出電壓取得同步於電容電流之斜坡資訊。為了降低穩態誤差，利用誤差放大器取得誤差訊號來調整輸出電壓準位；相較於補償器，此架構擁有較高的頻寬。穩態操作時，藉由磁滯控制的特性，利用含有誤差訊號及斜坡資訊在固定準位之磁滯窗內產生責任訊號。其中，磁滯窗之上界為三角波，可有效減少頻率的變動，降低傳統磁滯控制不定頻的特性。暫態響應時，依據暫態之系統修正量設計誤差訊號增益，藉由感測訊號超越磁滯區間時產生一次的全開或全關加速電感電流追上負載電流加速輸出電壓回復時間。量測結果顯示穩壓器在穩態時切換頻率局限於1MHz左右，在負載變動量為750mA下，回復時間小於4µs。負載為150mA時獲得最高效率92.5%，最大負載為900mA。

This thesis proposes a capacitor-current based fixed frequency hysteretic controlled buck converter using near-optimum technique. To reduce the dependence on the equivalent series resistor (ESR) of output capacitor as well as power consumption while detecting the current information, the current is obtained from a derivative circuit which samples the output voltage. To decrease steady-state error, the error amplifier obtains error signal between the output voltage and reference voltage to adjust DC offset of output voltage. To stabilize the operation frequency in steady state, the derived ramp signal is adopted to refine the upper side of the hysteretic band. During load transient, the designed gain of error signal can decrease the overshoot and undershoot of output voltage and settling time. Testing results show that the designed circuit can restrict the switching frequency around 1MHz. The recovery time is less than 4µs for the 750mA load transient. The maximum efficiency of 92.5% is obtained at 150mA output current, while the maximum output current is 900mA.

[1] Y.-H. Lee, S.-C. Huang, S.-W. Wang, and K.-H. Chen, “Fast transient (FT) technique with adaptive phase margin (APM) for current mode DC-DC buck converters,” IEEE Transactions on Very Large Scale Integration (VLSI) Systems, vol. 20, no. 10, pp. 1781-1793, 2012.
[2] R. Redl, and J. Sun, “Ripple-based control of switching regulators—An overview,” IEEE Transactions on Power Electronics, vol. 24, no. 12, pp. 2669-2680, 2009.
[3] S. C. Huerta, P. Alou, J. Oliver, O. Garcia, J. Cobos, and A. Abou-Alfotouh, “Design methodology of a non-invasive sensor to measure the current of the output capacitor for a very fast non-linear control,” Applied Power Electronics Conference and Exposition, 2009. APEC 2009. Twenty-Fourth Annual IEEE, pp. 806-811, 2009.
[4] P. Y. Wu, and P. K. Mok, “A monolithic buck converter with near-optimum reference tracking response using adaptive-output-feedback,” IEEE journal of solid-state circuits, vol. 42, no. 11, pp. 2441-2450, 2007.
[5] Y. Zheng, H. Chen, and K. N. Leung, “A fast-response pseudo-PWM buck converter with PLL-based hysteresis control,” IEEE Transactions on Very Large Scale Integration (VLSI) Systems, vol. 20, no. 7, pp. 1167-1174, 2012.
[6] S. Kapat, and P. T. Krein, “Improved time optimal control of a buck converter based on capacitor current,” IEEE Transactions on Power Electronics, vol. 27, no. 3, pp. 1444-1454, 2012.
[7] S. Franco, Design with operational amplifiers and analog integrated circuits: McGraw-Hill New York, 2002.
[8] 德州儀器電源管理產品行銷經理, “電池操作型可攜式應用的直流電源轉換,” 新電子科技雜誌, 2004.
[9] T. Instruments, “Power management guide 2016,” pp. 3, 2016.
[10] 林瑞禮, "電力電子特論講義," 國立成功大學電機工程學系, 2007.
[11] EPARC, 電力電子學綜論(第二版), 台灣: 全華圖書, 2011.
[12] C. F. Lee, and P. K. Mok, “A monolithic current-mode CMOS DC-DC converter with on-chip current-sensing technique,” IEEE journal of solid-state circuits, vol. 39, no. 1, pp. 3-14, 2004.
[13] R. Mammano, “Switching power supply topology voltage mode vs. current mode,” Elektron Journal-South African Institute of Electrical Engineers, vol. 18, no. 6, pp. 25-27, 2001.
[14] J. Abu-Qahouq, H. Mao, and I. Batarseh, “Multiphase voltage-mode hysteretic controlled DC-DC converter with novel current sharing,” IEEE Transactions on Power Electronics, vol. 19, no. 6, pp. 1397-1407, 2004.
[15] T. Instruments, "Dual-Channel 6+2/5+3 D-CAP+TM Multiphase Step-Down Controller with PMBus and NVM," TPS53681 datasheet, 2017.
[16] L. Wong, and T. Man, “Steady state analysis of hysteretic control buck converters,” Power Electronics and Motion Control Conference, 2008. EPE-PEMC 2008. 13th, pp. 400-404, 2008.
[17] M. Zimnik, “Comparison of PWM voltage and current mode control schemes vs. improved hysteretic mode control in switch mode power supplies (SMPS),” bbs.dianyuan.com/bbs/u/0/1066039498.pdf, 2013.
[18] T.-H. Lee, J.-G. Kim, and K.-S. Yoon, “A CMOS buck converter with PFM/hysteretic mode,” SoC Design Conference (ISOCC), 2016 International, pp. 347-348, 2016.
[19] Y.-C. Lin, C.-J. Chen, D. Chen, and B. Wang, “A ripple-based constant on-time control with virtual inductor current and offset cancellation for DC power converters,” IEEE Transactions on Power Electronics, vol. 27, no. 10, pp. 4301-4310, 2012.
[20] C. Song, and J. L. Nilles, “High-accuracy hysteretic current-mode regulator for powering microprocessors,” Applied Power Electronics Conference and Exposition, 2006. APEC'06. Twenty-First Annual IEEE, pp. 4, 2006.
[21] C. J. Solis, and G. A. Rincón-Mora, “Stability analysis & design of hysteretic current-mode switched-inductor buck DC-DC converters,” Electronics, Circuits, and Systems (ICECS), 2013 IEEE 20th International Conference on, pp. 811-814, 2013.
[22] Z. Liu, J. Zhao, K. Qu, F. Li, and W. Cao, “A new hysteresis control buck converter with enhanced feedback ripple,” Power Electronics and Application Conference and Exposition (PEAC), 2014 International, pp. 972-976, 2014.
[23] H. P. Forghani-Zadeh, and G. A. Rincon-Mora, “Current-sensing techniques for DC-DC converters,” Circuits and Systems, 2002. MWSCAS-2002. The 2002 45th Midwest Symposium on, vol. 2, pp. II-II, 2002.
[24] S. Qu, “Modeling and design considerations of V2 controlled buck regulator,” Applied Power Electronics Conference and Exposition, 2001. APEC 2001. Sixteenth Annual IEEE, vol. 1, pp. 507-513, 2001.
[25] Y. Y. Mai, and P. K. Mok, “A constant frequency output-ripple-voltage-based buck converter without using large ESR capacitor,” IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 55, no. 8, pp. 748-752, 2008.
[26] G. Zhou, J. Xu, and J. Wang, “Constant-frequency peak-ripple-based control of buck converter in CCM: Review, unification, and duality,” IEEE Transactions on Industrial Electronics, vol. 61, no. 3, pp. 1280-1291, 2014.
[27] D. Meeks, and P. Power, “Loop stability analysis of voltage mode buck regulator with different output capacitor types–Continuous and discontinuous modes,” 2008.
[28] R. B. Ridley, “A new, continuous-time model for current-mode control (power convertors),” IEEE transactions on Power Electronics, vol. 6, no. 2, pp. 271-280, 1991.
[29] K.-Y. Hu, S.-M. Lin, and C.-H. Tsai, “A fixed-frequency quasi-V2 hysteretic buck converter with PLL-based two-stage adaptive window control,” IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 62, no. 10, pp. 2565-2573, 2015.
[30] S.-H. Lee, J.-S. Bang, K.-S. Yoon, S.-W. Hong, C.-S. Shin, M.-Y. Jung, and G.-H. Cho, “12.1 A 0.518 mm 2 quasi-current-mode hysteretic buck DC-DC converter with 3μs load transient response in 0.35 μm BCDMOS,” Solid-State Circuits Conference-(ISSCC), 2015 IEEE International, pp. 1-3, 2015.
[31] Y.-H. Lee, S.-J. Wang, and K.-H. Chen, “Quadratic differential and integration technique in V2 control buck converter with small ESR capacitor,” IEEE Transactions on Power Electronics, vol. 25, no. 4, pp. 829-838, 2010.
[32] S. C. Huerta, P. Alou, J. Á. Oliver, O. Garcia, J. A. Cobos, and A. M. Abou-Alfotouh, “Nonlinear control for DC-DC converters based on hysteresis of the Cout current with a frequency loop to operate at constant frequency,” IEEE Transactions on Industrial Electronics, vol. 58, no. 3, pp. 1036-1043, 2011.
[33] P. Li, L. Xue, P. Hazucha, T. Karnik, and R. Bashirullah, “A delay-locked loop synchronization scheme for high-frequency multiphase hysteretic DC-DC converters,” IEEE Journal of Solid-State Circuits, vol. 44, no. 11, pp. 3131-3145, 2009.
[34] C.-H. Tsai, S.-M. Lin, and C.-S. Huang, “A fast-transient quasi-V2 switching buck regulator using AOT control with a load current correction (LCC) technique,” IEEE Transactions on Power Electronics, vol. 28, no. 8, pp. 3949-3957, 2013.
[35] S. C. Huerta, A. Soto, P. Alou, J. A. Oliver, O. García, and J. A. Cobos, “Advanced control for very fast DC-DC converters based on hysteresis of the Cout current” IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 60, no. 4, pp. 1052-1061, 2013.
[36] 洪挺軒, “具最佳化回授電路之磁滯電容電流控制直流-直流降壓轉換器,” 成功大學電機工程學系學位論文, pp. 1-81, 2013.
[37] D. Terrell, Op Amps: Design, Application, and Troubleshooting: Elsevier, 1996.
[38] T. Schmitz, and M. Wong, “Choosing and using bypass capacitors,” Intersil Application Note 1325, 2011.
[39] B. Razavi, Design of Analog CMOS Integrated Circuits: McGraw-Hill Education, 2000.
[40] T. Instruments. "LM7171 very high speed, high output current, voltage feedback amplifier," http://www.ti.com/product/lm7171.
[41] M. Integrated, “Precision triangular-wave generator uses a single IC,” vol. APPLICATION NOTE 4362, 2010.
[42] S.-H. Chien, T.-H. Hung, S.-Y. Huang, and T.-H. Kuo, “A monolithic capacitor-current-controlled hysteretic buck converter with transient-optimized feedback circuit,” IEEE Journal of Solid-State Circuits, vol. 50, no. 11, pp. 2524-2532, 2015.
[43] Y. Kobori, N. Tsukiji, N. Takai, and H. Kobayashi, “High speed response single-inductor dual-output dc-dc converter with hysteretic control,” ICPEIE, Venice, Italy, 2014.