Publications

Journal Articles

J1.     Z. Luo, J. Liu, and H. Lee, “A high-efficiency 40.68-MHz single-stage dual-output regulating rectifier with ZVS and synchronous PFM control for wireless powering,” IEEE Journal of Solid-State Circuits (JSSC), accepted for publication.

J2.     C. Chen, J. Liu, and H. Lee, “Dual-path hybrid Dickson converter for high-ratio conversions in point-of-load applications,” IEEE Transactions on Industry Applications (TIA), vol. 59, no. 6, pp. 6914 – 6925, Dec. 2023.

J3.     Z. Luo, J. Liu, and H. Lee, “A 40.68MHz active rectifier with cycle-based on-/off-delay compensation for high-current biomedical implants,” IEEE Journal of Solid-State Circuits (JSSC), vol. 58, no. 2, pp. 345 – 356, Feb. 2023.

J4.     Q. Cheng, J. Liu, and H. Lee, “A wide-input-range low-profile adaptive delay compensated hysteretic LED driver with enhanced current accuracy,” IEEE Journal of Solid-State Circuits (JSSC), vol. 57, no. 8, pp. 2474 – 2485, Aug. 2022.

J5.     Q. Cheng, L. Cong, and H. Lee, “A 48V-to-80V input 2MHz adaptive ZVT-assisted bus converter with light-load efficiency improvement,” IEEE Journal of Solid-State Circuits (JSSC), vol. 57, no. 7, pp. 2196 – 2207, Jul. 2022.

J6.     J. Xiong, J. Liu, and H. Lee, “A continuous-time sigma-delta modulator with continuous-time delay based integrator,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 69, no. 3, pp. 914 – 918, Mar. 2022.

J7.     W. Han and H. Lee, “A 340nA-quiescent 80mA-load 0.02fs-FOM active-capacitor-based low-dropout regulator in standard 0.18mm CMOS,” IEEE Solid-State Circuits Letters (SSC-L), vol. 4, pp. 125 – 128, Jul. 2021.

J8.     S. Uprety and H. Lee, “A 0.65mW-to-1W photovoltaic energy harvester with irradiance-aware auto-configurable hybrid MPPT achieving >95% MPPT efficiency and 2.9ms FOCV transient time,” IEEE Journal of Solid-State Circuits (JSSC), vol. 56, no. 6, pp. 1827 – 1836, Jun. 2021.

J9.     Z. Hua, Q. Cheng, J. Liu, and H. Lee, “A 1.2A dual-output SC DC-DC regulator with continuous gate-drive modulation achieving ≤0.01mV/mA cross regulation,” IEEE Journal of Solid-State Circuits (JSSC), vol. 56, no. 5, pp. 1576 – 1587, May 2021.

J10.  C. Chen, J. Liu, and H. Lee, “A 2MHz 9 – 45V input 3-switch ZVS step-up / -down hybrid converter,” IEEE Journal of Solid-State Circuits (JSSC), vol. 56, no. 3, pp. 855 – 865, Mar. 2021. (Invited)

J11.  S. Prakash, H. Martinez-Garcia, M. H. Naderi, H. Lee, and J. Silva-Martinez, “An agile supply modulator with improved transient performance for power-efficient linear amplifier employing envelope tracking techniques,” IEEE Transactions on Power Electronics (TPEL), vol. 35, no. 4, pp. 4178 – 4191, Apr. 2020.

J12.  L. Cong and H. Lee, “A 1 – 2MHz 150 – 400V GaN-based isolated DC-DC bus converter with monolithic slope-sensing ZVS detection,” IEEE Journal of Solid-State Circuits (JSSC), vol. 53, no. 12, pp. 3434 – 3445, Dec. 2018. (Invited)

J13.  L. Cong, J. Liu, and H. Lee, “A high-efficiency low-profile zero-voltage-transition synchronous non-inverting buck-boost converter with auxiliary component sharing,” IEEE Transactions on Circuits and Systems I: Regular Papers (TCAS-I), vol. 66, no. 1, pp. 438 – 449, Jan. 2019.

J14.  Z. Liu and H. Lee, “A current-accuracy-enhanced wide-input-range DC-DC LED driver with feedforward synchronous current control,” IEEE Transactions on Circuits and Systems I: Regular Papers (TCAS-I), vol. 65, no. 11, pp. 3996 – 4006, Nov. 2018.

J15.  J. Xue and H. Lee, “A 2MHz 12V - 100V 90%-efficiency self-balancing ZVS reconfigurable three-level DC-DC regulator with constant-frequency adaptive-on-time V2 control and nanosecond-scale ZVS turn-on delay,” IEEE Journal of Solid-State Circuits (JSSC), vol. 51, no. 12, pp. 2854 – 2866, Dec. 2016. (Invited)

J16.  S. Uprety and H. Lee, “A 0.4W – 21W fast-transient global-search algorithm based integrated photovoltaic energy harvester with 99% GMPPT efficiency and 94% power efficiency,” IEEE Journal of Solid-State Circuits (JSSC), vol. 51, no. 9, pp. 2153 – 2167, Sep. 2016.

J17.  Z. Liu and H. Lee, “A wide-input-range efficiency-enhanced synchronous LED driver with adaptive resonant timing control,” IEEE Journal of Solid-State Circuits (JSSC), vol. 51, no. 8, pp. 1810 – 1825, Aug. 2016. (Invited)

J18.  L. Cong and H. Lee, “High-voltage high-frequency non-isolated multi-phase DC-DC converters with passive-saving two-phase QSW-ZVS technique,” Journal of Analog Integrated Circuits and Signal Processing (JAICSP), vol. 88, no. 2, pp. 303 – 317, Aug. 2016. (Invited)

J19.  H. Lee, “An auto-reconfigurable 2x/4x AC-DC regulator for wirelessly-powered biomedical implants with 28% link efficiency enhancement,” IEEE Transactions on Very Large Scale Integration Systems (TVLSI), vol. 24, no. 4, pp. 1598 – 1602, Apr. 2016.

J20.  Z. Liu and H. Lee, “A 26W 97%-efficiency fast-settling dimmable LED driver with dual-nMOS-sensing based glitch-tolerant synchronous current control for high-brightness solid-state lighting applications,” IEEE Journal of Solid-State Circuits (JSSC), vol. 50, no. 9, pp. 2174 – 2187, Sep. 2015.

J21.  J. Xue and H. Lee, “A 2MHz 60W zero-voltage switching synchronous non-inverting buck-boost converter with reduced component values,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 62, no. 7, pp. 716 – 720, Jul. 2015.

J22.  Z. Liu, L. Cong, and H. Lee, “Design of on-chip gate drivers with power-efficient high-speed level shifting and dynamic timing control for high-voltage synchronous switching power converters,” IEEE Journal of Solid-State Circuits (JSSC), vol. 50, no. 6, pp. 1463 – 1477, Jun. 2015.

J23.  J. Xue and H. Lee, “Enabling high-frequency high-efficiency non-isolated boost converters with quasi-square-wave zero-voltage switching and on-chip dynamic dead-time controlled synchronous gate drive,” IEEE Transactions on Power Electronics (TPEL), vol. 30, no. 12, pp. 6817 – 6828, Dec. 2015.

J24.  H. Lee, Z. Hua, and X. Zhang, “A reconfigurable 2x/2.5x/3x/4x SC DC-DC regulator with fixed on-time control for transcutaneous power transmission,” IEEE Transactions on Very Large Scale Integration Systems (TVLSI), vol. 23, no. 4, pp. 712 – 722, Apr. 2015.

J25.  Z. Hua and H. Lee, “A reconfigurable dual-output switched-capacitor DC-DC regulator with sub-harmonic adaptive-on-time control for low-power applications,” IEEE Journal of Solid-State Circuits (JSSC), vol. 50, no. 3, pp. 724 – 736, Mar. 2015.

J26.  Z. Liu and H. Lee, “Design of high-performance integrated dimmable LED driver for high-brightness solid-state lighting applications,” Journal of Analog Integrated Circuits and Signal Processing (JAICSP), vol. 82, no. 3, pp. 519 – 532, Mar. 2015. (Invited)

J27.  D. Park and H. Lee, “Improvements in light-load efficiency and operation frequency for low-voltage current-mode integrated boost converters,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 61, no. 8, pp. 599 – 603, Aug. 2014.

J28.  D. Park, Z. Liu, and H. Lee, “A 40V 10W 93%-efficiency current-accuracy-enhanced dimmable LED driver with adaptive timing difference compensation for solid-state lighting applications,” IEEE Journal of Solid-State Circuits (JSSC), vol. 49, no. 8, pp. 1848 – 1860, Aug. 2014. (Invited)

J29.  X. Yu, J. Liu, B. Payne, M. Morgan, and H. Lee, “A 5Gb/s automatic sub-bit between-pair skew compensator for parallel data communication in 0.13mm CMOS,” IEEE Transactions on Very Large Scale Integration Systems (TVLSI), vol. 21, no. 12, pp. 2274 – 2285, Dec. 2013.

J30.  X. Zhang and H. Lee, “Gain-enhanced monolithic charge pump with simultaneous dynamic gate and substrate control,” IEEE Transactions on Very Large Scale Integration Systems (TVLSI), vol. 21, no. 3, pp. 593 – 596, Mar. 2013.

J31.  Y. Li, J. Liu, and H. Lee, “Ground switching load modulation with ground isolation for passive HF RFID transponders,” IEEE Transactions on Very Large Scale Integration Systems (TVLSI), vol. 20, no. 8, pp. 1443 – 1452, Aug. 2012.

J32.  D. Kim, V. Gopalakrishna, S. Guo, H. Lee, M. Torlak, N. Kehtamavaz, A. Lobo, and P. Loizou, “On the design of a flexible stimulator for animal studies in auditory prostheses,” Biomedical Signal Processing and Control (BSPC), vol. 6, no. 4, pp. 346 – 355, Oct. 2011.

J33.  M. Du, H. Lee, and J. Liu, “A 5-MHz 91% peak-power-efficiency buck regulator with auto-selectable peak- and valley-current control,” IEEE Journal of Solid-State Circuits (JSSC), vol. 46, no. 8, pp. 1928 – 1939, Aug. 2011. (Invited)

J34.  S. Guo and H. Lee, “Dual active-capacitive-feedback compensation for low-power large-capacitive-load three-stage amplifiers,” IEEE Journal of Solid-State Circuits (JSSC), vol. 46, no. 2, pp. 452 – 464, Feb. 2011.

J35.  M. Al-Shyoukh and H. Lee, “A compact fully-integrated extremum-selector-based soft-start circuit for voltage regulators,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 57, no. 10, pp. 818 – 822, Oct. 2010.

J36.  X. Zhang and H. Lee, “An efficiency-enhanced auto-reconfigurable 2x/3x SC charge pump for transcutaneous power transmission,” IEEE Journal of Solid-State Circuits (JSSC), vol. 45, no. 9, pp. 1906 – 1922, Sep. 2010.

J37.  M. Du and H. Lee, “An integrated speed- and accuracy-enhanced CMOS current sensor with dynamically-biased shunt feedback for current-mode buck regulators,” IEEE Transactions on Circuits and Systems I: Regular Papers (TCAS-I), vol. 57, no. 10, pp. 2804 – 2814, Oct. 2010.

J38.  H. Lee and S. Ryu, “An efficiency-enhanced DCM buck regulator with improved switching timing of power transistors,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 57, no. 3, pp. 238 – 242, Mar. 2010.

J39.  J. Yao, J. Liu, and H. Lee, “Bulk voltage trimming offset calibration for high-speed Flash ADCs,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 57, no. 2, pp. 110 – 114, Feb. 2010.

J40.  S. Guo and H. Lee, “Single-capacitor active-feedback compensation for small-capacitive-load three-stage amplifiers,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 56, no. 10, pp. 758 – 762, Oct. 2009.

J41.  M. Al-Shyoukh and H. Lee, “A compact ramp-based soft-start circuit for voltage regulators,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 56, no. 7, pp. 535 – 539, Jul. 2009.

J42.  S. Guo and H. Lee, “An efficiency-enhanced CMOS rectifier with unbalanced-biased comparators for transcutaneous-powered high-current implants,” IEEE Journal of Solid-State Circuits (JSSC), vol. 44, no. 6, pp. 1796 – 1804, Jun. 2009.

J43.  M. Al-Shyoukh, H. Lee, and R. Perez, “A transient-enhanced low-quiescent current low-dropout regulator with buffer impedance attenuation,” IEEE Journal of Solid-State Circuits (JSSC), vol. 42, no. 8, pp. 1732 – 1742, Aug. 2007. (Invited)

J44.  H. Lee and P. K. T. Mok, “An SC voltage doubler with pseudo-continuous output regulation using a three-stage switchable opamp,” IEEE Journal of Solid-State Circuits (JSSC), vol. 42, no. 6, pp. 1216 – 1229, Jun. 2007.

J45.  X. F. Lin, J. Liu, H. Lee, and H. Liu, “A 2.5- to 3.5-Gb/s adaptive FIR equalizer with continuous-time wide bandwidth delay line in 0.25mm CMOS,” IEEE Journal of Solid-State Circuits (JSSC), vol. 41, no. 8, pp. 1908 – 1918, Aug. 2006. (Invited)

J46.  H. Lee, P. K. T. Mok, and K. N. Leung, “Design of low-power analog driver based on slew-rate-enhancement circuit for CMOS low-dropout regulators,” IEEE Transactions on Circuits and Systems II: Express Briefs (TCAS-II), vol. 52, no. 9, pp. 563 – 567, Sep. 2005.

J47.  H. Lee and P. K. T. Mok, “Switching noise and shoot-through current reduction techniques for switched-capacitor voltage doubler,” IEEE Journal of Solid-State Circuits (JSSC), vol. 40, no. 5, pp. 1136 – 1146, May 2005.

J48.  H. Lee and P. K. T. Mok, “Advances in active-feedback frequency compensation with power optimization and transient improvement,” IEEE Transactions on Circuits and Systems I: Regular Papers (TCAS-I), vol. 51, no. 9, pp. 1690 – 1696, Sep. 2004.

J49.  H. Lee, K. N. Leung, and P. K. T. Mok, “A dual-path bandwidth extension amplifier topology with dual-loop parallel compensation,” IEEE Journal of Solid-State Circuits (JSSC), vol. 38, no. 10, pp. 1739 – 1744, Oct. 2003.

J50.  H. Lee and P. K. T. Mok, “Active-feedback frequency-compensation technique for low-power multistage amplifiers,” IEEE Journal of Solid-State Circuits (JSSC), vol. 38, no. 3, pp. 511 – 520, Mar. 2003. (Invited)

Conference Articles

C1.    Z. Luo, J. Liu, and H. Lee, “A 90%-efficiency 40.68MHz single-stage dual-output regulating rectifier with ZVS and synchronous PFM control for wireless powering,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, Feb. 2023, pp. 454 – 455.

C2.    W. Han, C. Chen, J. Liu, and H. Lee, “An 80A 48V-input capacitor-assisted dual-inductor hybrid Dickson converter for large-conversion ratio applications,” in Proc. IEEE Energy Conversion Congress and Exposition (ECCE), Detroit, MI, USA, Oct. 2022, pp. 1 – 4.

C3.    J. Xiong, J. Zhao, J. Liu, and H. Lee, “A 3rd order CT-SD modulator with a hybrid loop filter employing passive and continuous-time delay-based integrators,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), Austin, TX, May 2022, pp. 1230 – 1233.

C4.    W. Han, Z. Luo, C. Chen, J. Liu, and H. Lee, “A 200mA-load 0.62fs-FOM active-capacitor-assisted dual-loop output capacitorless low-dropout regulator in standard 65nm CMOS,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), Austin, TX, May 2022, pp. 1906 – 1909.

C5.    C. Chen, J. Liu, and H. Lee, “A 2.5 – 5MHz 87% peak efficiency 48V-to-1V integrated hybrid DC-DC converter adopting ladder SC network with capacitor-assisted dual inductor filtering,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, Feb. 2022, pp. 234 – 235.

C6.    C. Chen, J. Liu, and H. Lee, “A 2 – 5MHz multiple DC output hybrid boost converter with scalable CR boosting scheme achieving 91% efficiency at a conversion ratio of 12,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, Feb. 2022, pp. 310 – 311.

C7.    W. Han, Q. Chen, C. Chen, and H. Lee, “Conductive EMI reduction techniques for soft-switched half-bridge buck converters in automotive applications,” in Proc. IEEE Applied Power Electronics Conference (APEC), Houston, TX, USA, Mar. 2022, pp. 646 – 649.

C8.    Z. Luo and H. Lee, “A 87.2%-efficiency 27.12MHz current-mode wireless power receiver with ramp-assisted energy delivery controller for implantable devices,” in Proc. IEEE Asian Solid-State Circuits Conference (A-SSCC), Nov. 2021, pp. 1 – 3.

C9.    Z. Luo and H. Lee, “A 40.68MHz active rectifier with cycle-based on/off-delay compensation for biomedical implants,” in Proc. IEEE 47th European Solid-State Circuits Conference (ESSCIRC), Sep. 2021, pp. 227 – 230.

C10. C. Chen, J. Liu, and H. Lee, “A 92.7%-efficiency 30A 48V-to-1V dual-path hybrid Dickson converter for PoL applications,” in Proc. IEEE Energy Conversion Congress and Exposition (ECCE), Oct. 2021, pp. 1989 – 1994.

C11. Q. Cheng, J. Liu, and H. Lee, “A 5 – 100V input low-profile adaptive delay compensated hysteretic LED driver with enhanced current accuracy,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Apr. 2021, pp. 1 – 2. (Nominated for Best Student Paper Award)

C12. C. Chen, J. Liu, and H. Lee, “A 9 – 45V input 2MHz 3-switch ZVS step-up / -down hybrid converter with 5x volume reduction,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Mar. 2020, pp. 1 - 4. (Nominated for Best Student Paper Award)

C13. Q. Cheng, L. Cong, and H. Lee, “A 48-to-80V input 2MHz adaptive ZVT-assisted GaN-based bus converter achieving 14% light-load efficiency enhancement,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, USA, Feb. 2020, pp. 196 – 197.

C14. Z. Hua and H. Lee, “Ratio extension technique for Ladder- / Dickson-based multiple-output switched-capacitor DC-DC converters,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Dallas, TX, USA, Aug. 2019, pp. 933 – 936.

C15. S. Zhang, M. Zhao, and H. Lee, “A current-density-enhanced 12V-to-1.2V/10A, AOT controlled, 4-phase series-capacitor buck converter with embedded current balancing,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Dallas, TX, USA, Aug. 2019, pp. 802 – 805.

C16. L. Cong and H. Lee, “A 2MHz 150-400V input isolated DC-DC bus converter with monolithic slope-sensing ZVS detection achieving 13ns turn-on delay and 1.6W power saving,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, USA, Feb. 2018, pp. 382 – 383.

C17. Q. Cheng and H. Lee, “A high-frequency non-isolated ZVS synchronous buck-boost LED driver with fully integrated dynamic dead-time controlled gate drive,” in Proc. IEEE Applied Power Electronics Conference (APEC), San Antonio, TX, USA, Mar. 2018, pp. 419 – 422.

C18. L. Cong and H. Lee, “A 150V monolithic synchronous gate driver with built-in ZVS detection for half-bridge converters,” in Proc. IEEE Applied Power Electronics Conference (APEC), San Antonio, TX, USA, Mar. 2018, pp. 1861 – 1864.

C19. Z. Hua and H. Lee, “A 1.2A auto-configurable dual-output switched-capacitor DC-DC regulator with continuous gate-drive modulation achieving ≤0.01mV/mA cross regulation,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Austin, TX, USA, May 2017, pp. 1 – 4.

C20. S. Uprety and H. Lee, “A 93%-power-efficiency photovoltaic energy harvester with irradiance-aware auto-reconfigurable MPPT scheme achieving >95% MPPT efficiency across 650µW to 1W and 2.9ms FOCV MPPT transient time,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, USA, Feb. 2017, pp. 378 – 379.

C21. Z. Hua and H. Lee, “Design of area-efficient multiple-output switched-capacitor DC-DC converters,” in Proc. IEEE Applied Power Electronics Conference (APEC), Tampa, FL, USA, Mar. 2017, pp. 2217 – 2221.

C22. J. Xue and H. Lee, “A 2MHz 12 – 100V 90%-efficiency self-balancing ZVS three-level DC-DC regulator with constant-frequency AOT V2 control and 5ns ZVS turn-on delay,” in IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, San Francisco, CA, USA, Feb. 2016, pp. 226 – 227.

C23. Z. Liu and H. Lee, “A 5 – 115V efficiency-enhanced synchronous LED driver with adaptive resonant timing control,” IEEE Custom Integrated Circuits Conference (CICC), San Jose, CA, USA, Sep. 2015, pp. 1 – 4.

C24. L. Cong and H. Lee, “A 110 – 250V 2MHz isolated DC-DC converter with integrated high-speed synchronous three-level gate drive,” in Proc. IEEE Energy Conversion Congress and Exposition (ECCE), Montreal, Canada, Sep. 2015, pp. 1479 – 1484.

C25. H. Lee and T. Duryea, “A low-cost closed-form transient model for area-efficient on-chip power MOS sizing and reliable inductive load switching,” in Proc. IEEE Energy Conversion Congress and Exposition (ECCE), Montreal, Canada, Sep. 2015, pp. 2112 – 2115.

C26. J. Xue, L. Cong, and H. Lee, “A high-efficiency high-frequency GaN-based three-level isolated DC-DC converter with dynamic dead-time controlled synchronous gate drive,” 17th SRC Annual TECHCON Conference, Austin, TX, USA, Mar. 2015, (4 pages). (Best in Session Award)

C27. J. Xue, L. Cong, and H. Lee, “A 100-V 2-MHz isolated QSW-ZVS three-level DC-DC converter with on-chip dynamic dead-time controlled synchronous gate driver for eGaN power FETs,” in Proc. IEEE Applied Power Electronics Conference (APEC), Charlotte, NC, USA, Mar. 2015, pp. 451 – 454.

C28. L. Cong, J. Xue, and H. Lee, “A 100-V reconfigurable synchronous gate driver with comparator-based dynamic dead-time control for high-voltage high-frequency DC-DC converters,” in Proc. IEEE Applied Power Electronics Conference (APEC), Charlotte, NC, USA, Mar. 2015, pp. 2007 – 2010.

C29. Z. Hua and H. Lee, “Adaptive-on-time control technique for output ripple reduction and light-load efficiency enhancement in low-power switched-capacitor DC-DC regulators,” in Proc. IEEE Applied Power Electronics Conference (APEC), Charlotte, NC, USA, Mar. 2015, pp 1930 – 1933.

C30. Z. Liu, J. Xue, L. Cong, and H. Lee, “Building high-frequency high-voltage switching converters for renewable energy systems,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), College Station, TX, USA, Aug. 2014, pp. 346 – 349.

C31. L. Cong, J. Xue, and H. Lee, “A 140W 97% 4MHz two-phase buck converter with quasi-square-wave ZVS scheme,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), College Station, TX, USA, Aug. 2014, pp. 769 – 772.

C32. S. Uprety and H. Lee, “A 43V 400mW – 21W global-search-based photovoltaic energy harvester with 350us transient time, 99.9% MPPT efficiency and 94% power efficiency,” in IEEE International Solid-State Circuits Conference Dig. Tech. Papers (ISSCC), San Francisco, CA, USA, Feb. 2014, pp. 404 – 405.

C33. J. Xue, L. Cong, and H. Lee, “A 130W 95%-efficiency 1MHz non-isolated boost converter using PWM zero-voltage switching and enhancement-mode GaN FETs,” in Proc. IEEE Applied Power Electronics Conference (APEC), Fort Worth, TX, USA, Mar. 2014, pp. 471 – 475.

C34. Z. Liu and H. Lee, “A 25W 97%-efficiency 3.5MHz integrated dimmable LED driver with lossless synchronous current control and floating nMOS sensing scheme,” in Proc. IEEE Applied Power Electronics Conference (APEC), Fort Worth, TX, USA, Mar. 2014, pp. 1378 – 1383.

C35. Z. Liu and H. Lee, “A 100V gate driver with sub-nanosecond-delay level shifting and dynamic dead-time control for ZVS-based synchronous power converters,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), San Jose, CA, USA, Sep. 2013, pp. 1 – 4.

C36. D. K. Park and H. Lee, “A 40V 10W 93%-efficiency current-accuracy-enhanced dimmable LED driver with adaptive timing difference compensation for solid-state lighting applications,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), San Jose, CA, USA, Sep. 2013, pp. 1 – 4. (CICC Student Scholarship Award and Nominated for Best Student Paper Award)

C37. K. Flores and H. Lee, “An auto-reconfigurable load-dependent wireless power receiver for biomedical implants,” 15th Annual SRC TECHCON Conference, Austin, TX, USA, Sep. 2013 (4 pages). (Best in Session Award)

C38. Z. Liu and H. Lee, “A synchronous LED driver with dynamic level shifting and simultaneous peak and valley current control for high-brightness lighting applications,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Columbus, Ohio, USA, Aug. 2013, pp. 125 – 128. (Nominated for Best Student Paper Award)

C39. Z. Hua and H. Lee, “A cross-regulation-free triple-output switched-capacitor power regulator for energy-harvesting applications,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Columbus, Ohio, USA, Aug. 2013, pp. 352 – 355.

C40. J. Xue, K. Ngo, and H. Lee, “A 1.6-kW 99%-efficiency zero-voltage-switching boost converter using normally-off GaN power transistors and adaptive dead-time controlled on-chip gate drivers,” in Proc. IEEE International Conference on Electron Device and Solid-State Circuits (ICEDSSC), Hong Kong, China, Jun. 2013, pp. 1 – 2.

C41. H. Lee and Z. Hua, “Power- and area-efficiency enhancement technique of switched capacitor power converters for low-power applications,” in Proc. IEEE International Conference on Electron Devices and Solid-State Circuits (ICEDSSC), Hong Kong, China, Jun. 2013, pp. 1 – 2.

C42. Z. Hua, H. Lee, and X. Zhang, “A reconfigurable dual-output switched-capacitor power regulator with sub-harmonic fixed-on-time control for energy-harvesting applications,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), Beijing, China, May 2013, pp. 1472 – 1475.

C43. D. Park and H. Lee, “A high-efficiency high-accuracy output-capacitor-less integrated LED driver with time-to-digital control for solid-state lighting applications,” 14th Annual SRC TECHCON Conference, Austin, TX, USA, Sep. 2012 (4 pages).

C44. M. Du and H. Lee, “A high-efficiency auto-reconfigurable SITIDO boost/buck regulator with input power conditioning for energy-harvesting applications,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Boise, Idaho, USA, Aug. 2012, pp. 1092 – 1095.

C45. J. Hua, H. Lee, and K. King, “An event-driven ultra-low-current battery management system with reconfigurable linear regulator for multi-cell battery applications,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), Seoul, Korea, May. 2012, pp. 970 – 973.

C46. X. Zhang and H. Lee, “A power- and area-efficient integrated power management system for inductively-powered biomedical implants,” in Proc. IEEE Biomedical Circuits and Systems Conference (BioCAS), San Diego, CA, USA, Nov. 2011, pp. 213 – 216.

C47. X. Zhang and H. Lee, “A reconfigurable 2x/2.5x/3x/4x SC dc-dc regulator for enhancing area and power efficiencies in transcutaneous power transmission,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), San Jose, CA, USA, Sep. 2011, pp. 1 – 4.

C48. M. Du and H. Lee, “Area- and power-efficient single-inductor multiple-input multiple-output regulators for energy-harvesting applications,” 13th Annual SRC TECHCON Conference, Austin, TX, USA, Sep. 2011 (4 pages).

C49. M. Du, H. Lee, and J. Liu, “A reconfigurable SITITO boost/buck regulator with sub-threshold cross-regulation-free dual-mode control for energy-harvesting applications,” IEEE Symposium on VLSI Circuits (VLSI-C) Dig. Tech. Papers, Kyoto, Japan, Jun. 2011, pp. 240 – 241.

C50. M. Du and H. Lee, “A 5-MHz 91% peak power efficiency current-mode buck regulator with an auto-switchable peak- and valley-current control scheme,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), San Jose, CA, USA, Sep. 2010, pp. 1 – 4. (CICC Student Scholarship Award and Nominated for Best Student Paper Award)

C51. M. Du and H. Lee, “A single-inductor dual-input dual-output buck regulator with enhanced power-delivery capability for portable power management system,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Seattle, WA, USA, Aug. 2010, pp. 1141 – 1144.

C52. H. Lee and M. Al-Shyoukh, “Stability and transient-response enhancement techniques for low-dropout regulators,” in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), Seattle, WA, USA, Aug. 2010, pp. 580 – 583.

C53. Y. Zheng, J. Liu, R. Payne, M. Morgan, and H. Lee, “A 5-Gb/s automatic sub-bit between-pair skew compensator for parallel data communications in 0.13mm CMOS,” in Proc. IEEE Symposium on VLSI Circuits (VLSI-C), Honolulu, Hawaii, USA, Jun. 2010, pp. 71 – 72.

C54. M. Al-Shyoukh and H. Lee, “A current-limiter-based soft-start scheme for linear and low-dropout regulators,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), May 2010, pp. 2738 – 2741.

C55. T. Duryea and H. Lee, “Compact temperature compensation of inductive fly-back clamps for integrated power switches using a high-voltage base-current-compensated VBE multiplier,” in Proc. IEEE Applied Power Electronics Conference and Exposition (APEC), Feb. 2010, pp. 686 – 690.

C56. H. Lee, “A low-voltage low-power comparator with current-controlled dynamically-biased preamplifiers for DCM buck regulators,” in Proc. IEEE International Conference on Electronic Circuits and Systems (ICECS), Yasmine Hammamet, Tunisia, Dec. 2009, pp. 371 – 374.

C57. D. Kim, V. Gopalakrishna, S. Guo, H. Lee, M. Torlak, N. K. Ketharnavaz, A. Lobo, and P. Loizou, “On the design of a flexible stimulator for animal studies in auditory prosthesis,” in Proc. International Symposium on Applied Science in Biomedical and Communication Technologies, Nov. 2009, pp. 1 – 5.

C58. S. Guo and H. Lee, “Biphasic-current-pulse self-calibration techniques for monopolar current stimulation,” in Proc. IEEE Biomedical Circuits and Systems Conference (BioCAS), Nov. 2009, pp. 61 – 64.

C59. X. Zhang and H. Lee, “An efficiency-enhanced auto-reconfigurable 2x/3x SC charge pump for transcutaneous power transmission,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Sep. 2009, pp. 311 – 314.

C60. S. Guo, H. Lee, and P. Loizou, “A 9-bit configurable current source with enhanced output resistance for cochlear stimulators,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Sep. 2008, pp. 511 – 513.

C61. M. Du and H. Lee, “A 2.5MHz, 97%-accuracy on-chip current sensor with dynamically-biased shunt feedback for current-mode switching dc-dc converters,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), May 2008, pp. 3274 – 3277.

C62. M. Du and H. Lee, “A speed- and accuracy-enhanced on-chip current sensor with local shunt feedback for current-mode switching dc-dc converters,” in Proc. IEEE Dallas Circuits and Systems Workshop (DCAS), Dallas, TX, USA, Nov. 2007, pp. 129 – 132.

C63. X. Zhang and H. Lee, “An 88%-power efficiency accuracy-enhanced dc-dc conversion system for transcutaneous-powered cochlear implants,” in Proc. IEEE Biomedical Circuits and Systems Conference (BioCAS), Montreal, Canada, Nov. 2007, pp. 126 - 129.

C64. S. Guo and H. Lee, “An efficiency-enhanced integrated CMOS rectifier with comparator-controlled switches for transcutaneous powered implants,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Sep. 2007, pp. 385 – 388.

C65. S. Guo and H. Lee, “An area-efficient three-stage amplifier with dual active-capacitive-feedback compensation,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), May 2007, pp. 2188 – 2192.

C66. A. P. Lobo, P. C. Loizou, N. Kehtarnavaz, M. Torlak, H. Lee, A. Sharma, P. Gilley, V. Peddigari, and L. Ramanna, “A PDA-based research platform for cochlear implants,” in Proc. International IEEE/EMBS Conference on Neural Engineering, May 2007, pp. 28 – 31.

C67. A. P. Lobo, P. Loizou, N. Kehtarnavaz, M. Torlak, H. Lee, A. Sharma, P. Gilley, V. Peddigari, and L. Ramanna, “A portable research platform for cochlear implants,” Conference on Implantable Auditory Prostheses, Lake Tahoe, CA, USA, Jul. 2007.

C68. M. Al-Shyoukh, R. A. Perez, and H. Lee, “A transient-enhanced 20mA-quiescent 200mA-load low-dropout regulator with buffer impedance attenuation,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Sep. 2006, pp. 615 – 618.

C69. S. Guo and H. Lee, “A low-power active substrate-noise decoupling circuit with feedforward compensation for mixed-signal SoCs,” in Proc. IEEE International Symposium on Low Power Electronics and Design (ISLPED), Oct. 2006, pp. 322 – 325.

C70. S. Kwon and H. Lee, “A 1.2V, 3.5µW, 20MS/s, 8-bit comparator with dynamic-biasing preamplifier,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), May 2006, pp. 4767 – 4770.

C71. J. Choi, J. Liu, and H. Lee, “A constant power limit feedforward control circuit for flyback converters,” in Proc. IEEE Applied Power Electronics and Exposition (APEC), Mar. 2006, pp. 19 – 23.

C72. G. B. Zhang, H. Lee, and J. Liu, “A 35nW/pixel 2D visual motion sensor,” in Proc. European Solid-State Circuits Conference (ESSCIRC), Sep. 2005, pp. 419 - 422.

C73. X. F. Lin, H. Lee, and J. Liu, “A continuous-time adaptive FIR equalizer with INV-AIL delay line for 2.5Gb/s data communication,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Sep. 2005, pp. 413 – 416.

C74. H. Lee, K. N. Leung, and P. K. T. Mok, “Low-voltage analog circuit techniques using bias-current re-utilization, self-biasing and signal superposition,” in Proc. IEEE International Conference on Electronic Devices and Solid-State Circuits (ICEDSSC), Dec. 2005, pp. 533 – 536.

C75. H. Lee and P. K. T. Mok, “A SC dc-dc converter with pseudo-continuous output regulation using a three-stage switchable opamp,” IEEE International Solid-State Circuits Conference (ISSCC) Dig. Tech. Papers, Feb. 2005, pp.288 – 289.

C76. H. Lee and P. K. T. Mok, “Switching noise reduction techniques for switched-capacitor voltage doubler,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), Sep. 2003, pp. 693 – 696.

C77. H. Lee and P. K. T. Mok, “Active-feedback frequency compensation for low-power multi-stage amplifiers,” in Proc. IEEE Custom Integrated Circuits Conference (CICC), May 2002, pp. 325 – 328. (Best Student Paper Award)

C78. H. Lee and P. K. T. Mok, “Single-point-detection slew-rate enhancement circuits for single-stage amplifiers,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), vol. II, May 2002, pp. 831 – 834.

C79. H. Lee and P. K. T. Mok, “A CMOS current-mirror amplifier with compact slew rate enhancement circuit for large capacitive load applications,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), vol. I, May 2001, pp. 220 – 223.

C80. H. Lee and P. K. T. Mok, “A novel voltage-control scheme for low-voltage dc-dc converters with fast transient recovery,” in Proc. IEEE International Symposium on Circuits and Systems (ISCAS), vol. I, May 2000, pp. 256 – 259.