Although the proposed system had optimal transition point between PWM and PFM modes, it still had something needs to improve. The VC
Calibration signal is used to correct
the PFM_S voltage to calibrate the variation of process issues. But the VCCalibration is the
artificial signal that is forced by function generator. It makes the system inflexible. Therefore, the improvement of the system is removing the artificial signal of VCCalibration to achieve
real adaptive mode-transition control in future works. That’s the system without extra signal to control the converter. All signals are produced by itself.Reference
[1] Hong-Wei Huang, Chia-Hsiang Lin, and Ke-Horng Chen, “Low-Dropout Regulators with Adaptive Reference Control and Dynamic Push-Pull Techniques for Enhancing Transient Performance,” the 34th
European Solid-State Circuits Conference (ESSCIRC),
Sep. 2008.[2] Huan-JenYang, Han-Hsiang Huang, Chi-Lin Chen, Ming-Hsin Huang, and Ke-Horng Chen, “Current Feedback Compensation (CFC) Technique for Adaptively Adjusting the Phase Margin in Capacitor-Free LDO Regulators,” 51th IEEE Int'l Midwest Symposium
on Circuits & Systems, Aug. 2008.
[3] Yung-Hsin Lin, Kuo-Lin Zheng, and Ke-Horng Chen, “Power MOSFET Array for Smooth Pole Tracking in LDO Regulator Compensation,”
50th IEEE Int'l Midwest Symposium on Circuits & Systems/5th IEEE Int'l Northeast Workshop on Circuits &
Systems, pp. 554-557, Aug. 2007.
[4] Behzad Razavi, Design of Analog CMOS Integrated Circuits, McGRAW-HILL, 2000.
[5] P. Favrat, P. Deval and M. J. Declercq, ”A high-efficiency CMOS voltage doubler,”
IEEE Journal of Solid-State Circuits, vol. 33, pp. 410-416, March 1998.
[6] Starzyk, J.A, Ying-Wei Jan and Fengjing Qiu, “A DC-DC charge pump design based on voltage doublers,” IEEE Trans. Circuits and Systems I, vol. 48, pp. 350-359, Mar. 2001.
[7] Chun-Yu Hsieh, Po-Chin Fan and Ke-Horng Chen, “A Dual Phase Charge Pump with Compact Size,” the 14th IEEE International Conference on Electronics, Circuits and
Systems, pp.202-205, Dec., 2007.
[8] Yean-Kuo Luo, Ke-Horng Chen, and Wei-Chou Hsu, “A Dual-Phase Charge Pump Regulator with Nano-Ampere Switched-Capacitor CMOS Voltage Reference for Achieving Low Output Ripples,”
the 15th IEEE International Conference on Electronics, Circuits and Systems, Sep., 2008.
[9] Cheung Fai Lee, Philip K. T. “A Monolithic Current-Mode CMOS DC-DC Converter with On-Chip Current-Sensing Technique,”. IEEE J. Solid-State Circuits. vol. 39, pp.3-13, Jan. 2004.
[10] Chi Yat Leung, Philip K.T. Mok, “A 1-V Integrated Current-Mode Boost Converter in Standard 3.3/5-V CMOS Technologies,” IEEE Journal of Solid-State Circuits, vol. 40, no. 11, Nov. 2005.
[11] Ming-Hsin Huang, Ke-Horng Chen, and Wei-Hsin Wei “Single-Inductor Dual-Output DC-DC Converters with High Light-Load Efficiency and Minimized Cross-Regulation for Portable Devices,” IEEE VLSI-Symposium on Technology and Circuits, June, 2008.
and Sy-Yen Kuo, “Dithering Skip Modulator with a Width Controller for Ultra-wide-load High-Efficiency DC-DC Converters,” 2006 IEEE Custom Integrated
Circuits Conference (CICC), Sep. 10-13, 2006.
[13] Hong-Wei Huang, Chun-Yu Hsieh, Ke-Horng Chen, and Sy-Yen Kuo, “Adaptive Frequency Control Technique for Enhancing Transient Performance of DC-DC Converters,” the 33rd European Solid-State Circuits Conference (ESSCIRC), pp.
174-177, Sep. 2007.
[14] Yu-Huei Lee, Shih-Jung Wang, Chun-Yu Hsieh, and Ke-Horng Chen, “Current Mode DC-DC Buck Converters with Optimal Fast-Transient Control,” ISCAS, May. 2008.
[15] Hong-Wei Huang, Hsin-Hsin Ho, Chieh-Ching Chien, Ke-Horng Chen, Gin-Kou Ma, and Sy-Yen Kuo, “Fast Transient DC-DC Converter with On-Chip Compensated Error Amplifier,” the 32nd European Solid-State Circuits Conference (ESSCIRC), pp. 324-327, Sep. 2006.
[16] Ke-Horng Chen, Hong-Wei Huang, and Sy-Yen Kuo, “Fast Transient DC-DC Converter with On-Chip Compensated Error Amplifier,” in IEEE Transactions on Circuits and
Systems II, pp. 1150-1154, Dec. 2007.
[17] Robert W. Erickson, Dragan Maksimović, Fundamentals of Power Electronics, Second Edition, University of Colorado, Kluwer Academic Publishers, 2001.
[18] Abraham I. Pressman, Switching Power Supply Design, McGraw-Hill, 1991.
[19] Hong-Wei Huang, Ke-Horng Chen, and Sy-Yen Kuo, “Highly Efficient Tri-Mode Control of Buck Converters,” 37th IEEE Power Electronics Specialists Conference
-2006, June 18-22, 2006.
[20] Chi-Lin Chen, Wei-Lun Hsieh, Han-Hsiang Huang, and Ke-Horng Chen, “Fast Mode-Switching Technique in Hybrid-Mode Operation,” 51th IEEE Int'l Midwest
Symposium on Circuits & Systems, Aug. 2008.
[21] Chiawei Liao, “Switching Regulator with Variable Slope Compensation,” U.S. Patent 2007/0013355, Jan 18, 2007.
[22] Chiawei Liao, “Switching Regulator with Slope Compensation Independent of changes in switching Frequency,” U.S. Patent 2007/0035283, Feb 15, 2007.
[23] Chiawei Liao, “Switching Regulator Slope Compensation Generator Circuit,” U.S.
Patent 2007/0108947, May 17, 2007.
[24] K. N. Leung, P. K .T. Mok, “A sub-1 V 15 ppm/°C CMOS Bandgap Voltage Reference without requiring Low Threshold Voltage Device,” IEEE J. Solid State Circuits, vol.
37, pp. 526-530, Apr. 2002.
[25] Phillip E. Allen and Douglas R. Holberg, CMOS Analog Circuit Design, Second edition, New York Oxford University Press, 2002.
[26] Hong-Wei Huang, Chun-Yu Hsieh, Ke-Horng Chen, and Sy-Yen Kuo, “A 1-V, 16.9 ppm/
°C, 250 nA Switched-Capacitor CMOS Voltage Reference,” IEEE ISSCC, Feb. 2008.
[27] David A. Johns and Ken Martin, Analog Integrated Circuit design, Wiley, 1996.
[28] Ke-Horng Chen, Chia-Jung Chang, and Ter-Hsing Liu, “Bidirectional Current-Mode Capacitor Multipliers for On-Chip Compensation,” in IEEE Transaction on Power
Electronics, pp. 180-188, Jan. 2008.
[29] Cheung Fai Lee and Philip K.T.Mok, ”A Monolithic Current-Mode CMOS Converter With On-Chip Current-Sensing Technique,” IEEE JOURNAL OF SOLID-STATE
CIRCUITS, vol. 39, no. 1, Jan. 2004.
[30] Hylas Y.H Lam, Wing-Hung Ki and Dongsheng Ma, “Loop gain analysis and development of high-speed high-accuracy current sensors for switching converters,”
ISCAS, 2004.
[31] Chi Yat Leung, Philip K. T. Mok, Ka Nang Leung, Mansun Chan “An Integrated CMOS Current-Sensing Circuit for Low-Voltage Current-Mode Buck Regulator,” IEEE Trans.
Circuits and System. vol. 52, no. 7, July 2005.
[32] Chi-Lin Chen, Wei-Jen Lai, Wei-Lun Hsieh, and Ke-Horng Chen, “A High-Speed and Precise Current Sensing Circuit with Bulk Control (CCB) Technique,”
the 15th IEEE International Conference on Electronics, Circuits and Systems, Sep., 2008.
[33] Shih-Min Chen, Chun-Yu Hsieh, and Ke-Horng Chen, “Challenge on Compact Size DC-DC Buck Converters with High Speed Current Sensor and on-Chip Inductors,” 50th
IEEE Int'l Midwest Symposium on Circuits & Systems/5th IEEE Int'l Northeast Workshop on Circuits & Systems, pp. 670-673, Aug. 2007.
[34] Hong-Wei Huang, Wei-Lun Hsieh, and Ke-Horng Chen, “Programmable Voltage-to-Current Converter with Linear Voltage Control Resistor,” ISCAS, May. 2008.
[35] Chi-Lin Chen, Wei-Jen Lai, Ter-Hsing Liu, and Ke-Horng Chen, “Zero Current Detection Technique for Fast Transient Response in Buck DC-DC Converters,” ISCAS, May. 2008.
[36] Hong-Wei Huang, Ke-Horng Chen, and Sy-Yen Kuo, “Dithering Skip Modulation, Width and Dead Time Controllers in Highly Efficient DC-DC Converters for System-on-chip Applications,” in IEEE Journal of Solid-State Circuits, pp. 2451-2465, Nov. 2007.
[37] Hong-Wei Huang, Chun-Yu Hsieh, Ke-Horng Chen, and Sy-Yen Kuo, “Load dependent Dead Time Controller Based on Minimized Duty cycle technique in DC-DC Buck Converters,” 38th IEEE Power Electronics Specialists Conference-2007, pp. 2037-2041, June, 2007.
[38] Chi-Lin Chen, Wei-Jen Lai, Wei-Lun Hsieh, and Ke-Horng Chen, “A New PWM/PFM Control Technique for Improving Efficiency Over Wide Load Range,”
the 15th IEEE International Conference on Electronics, Circuits and Systems, Sep., 2008.
[39] Ke-Horng Chen, Chieh-Ching Chien, and Li-Ren Huang, “Optimum Power-Saving Method for Power MOSFET Width of One-Cycle Control DC-DC Converters,” 37th