Continuous-Time Modeling of a Hysteretic DC-DC Converter Using an Amplifier Model in Place of the Hysteretic Comparator.

Nobukazu Takai

Yasuhiro Sugimoto Nobukazu Takai Continuous-Time Modeling of a Hysteretic DC-DC Converter Using an Amplifier Model in Place of the Hysteretic Comparator. 661-668 2025 108 IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 5 https://doi.org/10.1587/transfun.2024gcp0003 db/journals/ieiceta/ieiceta108.html#SugimotoT25 streams/journals/ieiceta

Kazuya Yamamoto Nobukazu Takai GNN-Opt: Enhancing Automated Circuit Design Optimization with Graph Neural Networks. 687-689 2025 108 IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 5 https://doi.org/10.1587/transfun.2024gcl0001 db/journals/ieiceta/ieiceta108.html#YamamotoT25 streams/journals/ieiceta

Yuto Moriguchi Nobukazu Takai Optimal Mapping of Monte Carlo Analysis for Analog Circuit Designing using Bayesian Neural Networks. 1-5 2025 AICAS https://doi.org/10.1109/AICAS64808.2025.11173097 conf/aicas/2025 db/conf/aicas/aicas2025.html#MoriguchiT25 streams/conf/aicas Tsuyoshi Masubuchi Nobukazu Takai Improving the Efficiency of Bayesian Optimization Using Robust Scaling Tchebycheff Method in Op-Amp Circuit Design. 1-4 2025 ICECS https://doi.org/10.1109/ICECS66544.2025.11270773 conf/icecsys/2025 db/conf/icecsys/icecsys2025.html#MasubuchiT25 streams/conf/icecsys Takayoshi Namura Nobukazu Takai Interpreting and Reducing Variables in Analog Circuit Sizing Models with Explainable AI. 177-181 2025 NewCAS https://doi.org/10.1109/NewCAS64648.2025.11107087 conf/newcas/2025 db/conf/newcas/newcas2025.html#NamuraT25 streams/conf/newcas Tsuyoshi Masubuchi Nobukazu Takai Op-Amp sizing with large number of design variables using TuRBO. 649-653 2024 APCCAS https://doi.org/10.1109/APCCAS62602.2024.10808437 conf/apccas/2024 db/conf/apccas/apccas2024.html#MasubuchiT24 Akihiro Saito Nobukazu Takai Satoshi Konno Determination of circuit topology and element values from desired characteristics by machine learning. 1-4 2020 ICECS https://doi.org/10.1109/ICECS49266.2020.9294885 conf/icecsys/2020 db/conf/icecsys/icecsys2020.html#SaitoTK20 Nobukazu Takai Masafumi Fukuda Masahiro Saruta Self-improvement of OPAmp parameters using Q-Learning. 293-296 2019 SMACD https://doi.org/10.1109/SMACD.2019.8795232 conf/smacd/2019 db/conf/smacd/smacd2019.html#TakaiFS19 Takayuki Arai Natsuko Miki Yifei Sun Nobukazu Takai Output Voltage Ripple Compensation for Switching Power Supply in EMI Reduction Method with Theoretical Analysis. 60-65 2018 ISPACS https://doi.org/10.1109/ISPACS.2018.8923230 conf/ispacs/2018 db/conf/ispacs/ispacs2018.html#AraiMST18 Teruki Matsuba Nobukazu Takai Masafumi Fukuda Yusuke Kubo Inference of Suitable for Required Specification Analog Circuit Topology using Deep Learning. 131-134 2018 ISPACS https://doi.org/10.1109/ISPACS.2018.8923544 conf/ispacs/2018 db/conf/ispacs/ispacs2018.html#MatsubaTFK18

Kento Suzuki Nobukazu Takai Yoshiki Sugawara Masato Kato Automatic Design of Operational Amplifier Utilizing both Equation-Based Method and Genetic Algorithm. 2750-2757 2017 100-A IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 12 https://doi.org/10.1587/transfun.E100.A.2750 http://search.ieice.org/bin/summary.php?id=e100-a_12_2750 db/journals/ieicet/ieicet100a.html#SuzukiTSK17

Masafumi Fukuda Tsukasa Ishii Nobukazu Takai OP-AMP sizing by inference of element values using machine learning. 622-627 2017 ISPACS https://doi.org/10.1109/ISPACS.2017.8266553 conf/ispacs/2017 db/conf/ispacs/ispacs2017.html#FukudaIT17 Tsukasa Ishii Nobukazu Takai Masafumi Fukuda Automatic design of the analog integrated circuit based on Equation-Based and Characterize results. 675-679 2017 ISPACS https://doi.org/10.1109/ISPACS.2017.8266562 conf/ispacs/2017 db/conf/ispacs/ispacs2017.html#IshiiTF17 Yasunori Kobori Nobukazu Tsukiji Takuya Arafune Manimel Wadu Sahan Dulara Yifei Sun Nobukazu Takai Haruo Kobayashi 0001 Noise spread spectrum with adjustable notch frequency in complex pulse coding controlled DC-DC converters. 752-757 2017 ISPACS https://doi.org/10.1109/ISPACS.2017.8266576 conf/ispacs/2017 db/conf/ispacs/ispacs2017.html#KoboriTASSTK17 Manimel Wadu Sahan Dulara Nobukazu Tsukiji Yasunori Kobori Koyo Asaishi Nobukazu Takai Haruo Kobayashi 0001 Delay-time suppression technique for DC/DC buck converter using voltage mode PWM control. 758-763 2017 ISPACS https://doi.org/10.1109/ISPACS.2017.8266577 conf/ispacs/2017 db/conf/ispacs/ispacs2017.html#DularaTKATK17 Natsuko Miki Nobukazu Tsukiji Koyo Asaishi Yasunori Kobori Nobukazu Takai Hamo Kobayashi EMI reduction technique with noise spread spectrum using swept frequency modulation for hysteretic DC-DC converters. 889-894 2017 ISPACS https://doi.org/10.1109/ISPACS.2017.8266601 conf/ispacs/2017 db/conf/ispacs/ispacs2017.html#MikiTAKTK17 Yasunori Kobori Takuya Arafune Nobukazu Tsukiji Nobukazu Takai Haruo Kobayashi 0001 Selectable notch frequencies of EMI spread spectrum using pulse modulation in switching converter. 1-4 2015 ASICON https://doi.org/10.1109/ASICON.2015.7517055 conf/asicon/2015 db/conf/asicon/asicon2015.html#KoboriATTK15 Yasunori Kobori Taifeng Wang Nobukazu Tsukiji Nobukazu Takai Haruo Kobayashi 0001 EMI reduction by analog noise spread spectrum in new ripple controlled converter. 1-4 2015 ASICON https://doi.org/10.1109/ASICON.2015.7517056 conf/asicon/2015 db/conf/asicon/asicon2015.html#KoboriWTTK15 Yoshiki Sugawara Nobukazu Takai Masato Kato Hiroaki Seki Kento Suzuki Haruo Kobayashi 0001 Automatic design of doubly-terminated RC polyphase filters by using distributed genetic algorithm. 1-4 2015 ASICON https://doi.org/10.1109/ASICON.2015.7516934 conf/asicon/2015 db/conf/asicon/asicon2015.html#SugawaraTKSSK15 Yoshiki Sunaga Naoya Shiraishi Koyo Asaishi Nobukazu Tsukiji Yasunori Kobori Nobukazu Takai Haruo Kobayashi 0001 High efficiency single-inductor dual-output DC-DC converter with ZVS-PWM control. 1-4 2015 ASICON https://doi.org/10.1109/ASICON.2015.7516895 conf/asicon/2015 db/conf/asicon/asicon2015.html#SunagaSATKTK15 Kento Suzuki Nobukazu Takai Masato Kato Hiroaki Seki Yoshiki Sugawara Haruo Kobayashi 0001 Comparator circuits automation by combination of distributed genetic algorithm and HSPICE optimization. 1-4 2015 ASICON https://doi.org/10.1109/ASICON.2015.7516958 conf/asicon/2015 db/conf/asicon/asicon2015.html#SuzukiTKSSK15 Nobukazu Takai Yoshiki Sugawara Kento Suzuki Takayuki Negishi Hiroaki Seki Masato Kato Automatic design of RC polyphase filters with small element value spread using genetic algorithm. 303-306 2015 ISPACS https://doi.org/10.1109/ISPACS.2015.7432785 conf/ispacs/2015 db/conf/ispacs/ispacs2015.html#TakaiSSNSK15

Satoshi Uemori Masamichi Ishii Haruo Kobayashi 0001 Daiki Hirabayashi Yuta Arakawa Yuta Doi Osamu Kobayashi Tatsuji Matsuura Kiichi Niitsu Yuji Yano Tatsuhiro Gake Takahiro J. Yamaguchi Nobukazu Takai Multi-bit Sigma-Delta TDC Architecture with Improved Linearity. 879-892 2013 29 J. Electron. Test. 6 https://doi.org/10.1007/s10836-013-5408-6 db/journals/et/et29.html#UemoriIKHADKMNYGYT13

Kentaroh Katoh Yuta Doi Satoshi Ito Haruo Kobayashi 0001 Ensi Li Nobukazu Takai An Analysis of Stochastic Self-Calibration of TDC Using Two Ring Oscillators. 140-146 2013 Asian Test Symposium https://doi.org/10.1109/ATS.2013.35 https://doi.ieeecomputersociety.org/10.1109/ATS.2013.35 conf/ats/2013 db/conf/ats/ats2013.html#KatohDIKLT13 Hong Gao 0006 Lin Xing Yasunori Kobori Feng Zhao Haruo Kobayashi 0001 Shyunsuke Miwa Atsushi Motozawa Zachary Nosker Kiichi Niitsu Nobukazu Takai Takahiro Odaguchi Isao Nakanishi Kenji Nemoto Jun-Ichi Matsuda DC-DC converter with continuous-time feed-forward Sigma-Delta modulator control. 65-68 2012 APCCAS https://doi.org/10.1109/APCCAS.2012.6418972 conf/apccas/2012 db/conf/apccas/apccas2012.html#GaoXKZKMMNNTONNM12 Yasunori Kobori Qiulin Zhu Murong Li Feng Zhao Zachary Nosker Shu Wu Shaiful N. Mohyar Masanori Onozawa Haruo Kobayashi 0001 Nobukazu Takai Kiichi Niitsu Takahiro Odaguchi Isao Nakanishi Kenji Nemoto Jun-Ichi Matsuda Asahi Kasei Single inductor dual output DC-DC converter design with exclusive control. 436-439 2012 APCCAS https://doi.org/10.1109/APCCAS.2012.6419065 conf/apccas/2012 db/conf/apccas/apccas2012.html#KoboriZLZNWMOKTNONNMK12 Guanglei Jin Hao Chen Chuan Gao Yunpeng Zhang Haruo Kobayashi 0001 Nobukazu Takai Kiichi Niitsu Khayrollah Hadidi Digitally-controlled Gm-C bandpass filter. 531-534 2012 APCCAS https://doi.org/10.1109/APCCAS.2012.6419089 conf/apccas/2012 db/conf/apccas/apccas2012.html#JinCGZKTNH12 Satoshi Uemori Masamichi Ishii Haruo Kobayashi 0001 Yuta Doi Osamu Kobayashi Tatsuji Matsuura Kiichi Niitsu Yuta Arakawa Daiki Hirabayashi Yuji Yano Tatsuhiro Gake Nobukazu Takai Takahiro J. Yamaguchi Multi-bit sigma-delta TDC architecture with self-calibration. 671-674 2012 APCCAS https://doi.org/10.1109/APCCAS.2012.6419124 conf/apccas/2012 db/conf/apccas/apccas2012.html#UemoriIKDKMNAHYGTY12

Tomohiko Ogawa Haruo Kobayashi 0001 Satoshi Uemori Yohei Tan Satoshi Ito Nobukazu Takai Takahiro J. Yamaguchi Kiichi Niitsu Design for Testability That Reduces Linearity Testing Time of SAR ADCs. 1061-1064 2011 94-C IEICE Trans. Electron. 6 https://doi.org/10.1587/transele.E94.C.1061 http://search.ieice.org/bin/summary.php?id=e94-c_6_1061 db/journals/ieicet/ieicet94c.html#OgawaKUTITYN11

Tomohiko Ogawa Haruo Kobayashi 0001 Yosuke Takahashi Nobukazu Takai Masao Hotta Hao San Tatsuji Matsuura Akira Abe Katsuyoshi Yagi Toshihiko Mori SAR ADC Algorithm with Redundancy and Digital Error Correction. 415-423 2010 93-A IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 2 https://doi.org/10.1587/transfun.E93.A.415 http://search.ieice.org/bin/summary.php?id=e93-a_2_415 db/journals/ieicet/ieicet93a.html#OgawaKTTHSMAYM10

Satoshi Uemori Takahiro J. Yamaguchi Satoshi Ito Yohei Tan Haruo Kobayashi 0001 Nobukazu Takai Kiichi Niitsu Nobuyoshi Ishikawa ADC linearity test signal generation algorithm. 44-47 2010 APCCAS https://doi.org/10.1109/APCCAS.2010.5774755 conf/apccas/2010 db/conf/apccas/apccas2010.html#UemoriYITKTNI10 Tomohiko Ogawa Tatsuji Matsuura Haruo Kobayashi 0001 Nobukazu Takai Masao Hotta Hao San Akira Abe Katsuyoshi Yagi Toshihiko Mori Non-binary SAR ADC with digital error correction for low power applications. 196-199 2010 APCCAS https://doi.org/10.1109/APCCAS.2010.5774747 conf/apccas/2010 db/conf/apccas/apccas2010.html#OgawaMKTHSAYM10 Tomohiko Ogawa Haruo Kobayashi 0001 Yohei Tan Satoshi Ito Satoshi Uemori Nobukazu Takai Kiichi Niitsu Takahiro J. Yamaguchi Tatsuji Matsuura Nobuyoshi Ishikawa SAR ADC that is configurable to optimize yield. 374-377 2010 APCCAS https://doi.org/10.1109/APCCAS.2010.5774845 conf/apccas/2010 db/conf/apccas/apccas2010.html#OgawaKTIUTNYMI10 Kenji Takahashi Hajime Yokoo Shyunsuke Miwa Kengo Tsushida Hiroyuki Iwase Kazuki Murakami Nobukazu Takai Haruo Kobayashi 0001 Takahiro Odaguchi Shigeki Takayama Isao Fukai Jun-Ichi Matsuda Single inductor DC-DC converter with bipolar outputs using charge pump. 460-463 2010 APCCAS https://doi.org/10.1109/APCCAS.2010.5774840 conf/apccas/2010 db/conf/apccas/apccas2010.html#TakahashiYMTIMTKOTFM10 Satoshi Ito Shigeyuki Nishimura Haruo Kobayashi 0001 Satoshi Uemori Yohei Tan Nobukazu Takai Takahiro J. Yamaguchi Kiichi Niitsu Stochastic TDC architecture with self-calibration. 1027-1030 2010 APCCAS https://doi.org/10.1109/APCCAS.2010.5774740 conf/apccas/2010 db/conf/apccas/apccas2010.html#ItoNKUTTYN10

Ibuki Mori Yoshihisa Yamada Santhos A. Wibowo Masashi Kono Haruo Kobayashi 0001 Yukihiro Fujimura Nobukazu Takai Toshio Sugiyama Isao Fukai Norihisa Onishi Ichiro Takeda Jun-Ichi Matsuda EMI Reduction by Spread-Spectrum Clocking in Digitally-Controlled DC-DC Converters. 1004-1011 2009 92-A IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 4 https://doi.org/10.1587/transfun.E92.A.1004 http://search.ieice.org/bin/summary.php?id=e92-a_4_1004&category=A&year=2009&lang=E&abst= db/journals/ieicet/ieicet92a.html#MoriYWKKFTSFOTM09

Nobukazu Takai Yukihiro Fujimura Steep Down-Slope Sawtooth Wave Generator Utilizing Two Triangluar Waves Exclusively. 1019-1023 2009 92-A IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 4 https://doi.org/10.1587/transfun.E92.A.1019 http://search.ieice.org/bin/summary.php?id=e92-a_4_1019&category=A&year=2009&lang=E&abst= db/journals/ieicet/ieicet92a.html#TakaiF09

Kazuya Shimizu Masato Kaneta HaiJun Lin Haruo Kobayashi 0001 Nobukazu Takai Masao Hotta A Time-to-Digital Converter with small circuitry. 109-110 2009 ASP-DAC https://doi.org/10.1109/ASPDAC.2009.4796456 http://dl.acm.org/citation.cfm?id=1509665 conf/aspdac/2009 db/conf/aspdac/aspdac2009.html#ShimizuKLKTH09 Tomohiko Ogawa Haruo Kobayashi 0001 Masao Hotta Yosuke Takahashi Hao San Nobukazu Takai SAR ADC algorithm with redundancy. 268-271 2008 APCCAS https://doi.org/10.1109/APCCAS.2008.4746011 conf/apccas/2008 db/conf/apccas/apccas2008.html#OgawaKHTST08 Akihiro Kanbe Masato Kaneta Fuminori Yui Haruo Kobayashi 0001 Nobukazu Takai Tatsuhiro Shimura Hitoshi Hirata Kentarou Yamagishi New architecture for envelope-tracking power amplifier for base station. 296-299 2008 APCCAS https://doi.org/10.1109/APCCAS.2008.4746018 conf/apccas/2008 db/conf/apccas/apccas2008.html#KanbeKYKTSHY08 Nobukazu Takai Yukihiro Fujimura Compensation method of amplitude error in sawtooth wave generator. 128-131 2007 ECCTD https://doi.org/10.1109/ECCTD.2007.4529553 conf/ecctd/2007 db/conf/ecctd/ecctd2007.html#TakaiF07

Nobukazu Takai Shigetaka Takagi Nobuo Fujii Rail-to-Rail OTA Based on Signal Decomposition. 424-430 http://search.ieice.org/bin/summary.php?id=e88-a_2_424&category=D&year=2005&lang=E&abst= 2005 88-A IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 2 db/journals/ieicet/ieicet88a.html#TakaiTF05

Nobukazu Takai Keigo Kawai Rail-to-Rail OTA Utilizing Linear V-I Conversion Circuit Whose Input Stage is Composed of Single Channel MOSFETs. 832-837 2005 88-A IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 4 https://doi.org/10.1093/ietfec/e88-a.4.832 db/journals/ieicet/ieicet88a.html#TakaiK05

Nobukazu Takai Shinji Nomura Rail-to-rail OTA utilizing linear V-I conversion circuit using single channel MOSFETs for input stage. 31-34 2005 ECCTD https://doi.org/10.1109/ECCTD.2005.1522902 conf/ecctd/2005 db/conf/ecctd/ecctd2005.html#TakaiN05 Nobukazu Takai Nobuo Fujii GaAs MESFET multi-output current mirrors and their application to high frequency filters. 307-310 1998 ICECS https://doi.org/10.1109/ICECS.1998.814887 conf/icecsys/1998 db/conf/icecsys/icecsys1998.html#TakaiF98 Akira Abe Takuya Arafune Takayuki Arai Yuta Arakawa Koyo Asaishi Hao Chen Yuta Doi Manimel Wadu Sahan DularaManimel Wadu Sahan Nobuo Fujii Yukihiro Fujimura Isao Fukai Masafumi Fukuda Tatsuhiro Gake Chuan Gao Hong Gao 0006 Khayrollah Hadidi Daiki Hirabayashi Hitoshi Hirata Masao Hotta Masamichi Ishii Tsukasa Ishii Nobuyoshi Ishikawa Satoshi Ito Hiroyuki Iwase Guanglei Jin Akihiro Kanbe Masato Kaneta Asahi Kasei Masato Kato Kentaroh Katoh Keigo Kawai Hamo Kobayashi Haruo Kobayashi 0001 Osamu Kobayashi Yasunori Kobori Satoshi Konno Masashi Kono Yusuke Kubo Ensi Li Murong Li Haijun LinHaiJun Lin Tsuyoshi Masubuchi Teruki Matsuba Jun-Ichi Matsuda Tatsuji Matsuura Natsuko Miki Shyunsuke Miwa Shaiful N. Mohyar Ibuki Mori Toshihiko Mori Yuto Moriguchi Atsushi Motozawa Kazuki Murakami Isao Nakanishi Takayoshi Namura Takayuki Negishi Kenji Nemoto Kiichi Niitsu Shigeyuki Nishimura Shinji Nomura Zachary Nosker Takahiro Odaguchi Tomohiko Ogawa Norihisa Onishi Masanori Onozawa Akihiro Saito Hao San Masahiro Saruta Hiroaki Seki Kazuya Shimizu Tatsuhiro Shimura Naoya Shiraishi Yoshiki Sugawara Yasuhiro Sugimoto Toshio Sugiyama Dulara Yifei Sun Yifei Sun Yoshiki Sunaga Kento Suzuki Shigetaka Takagi Kenji Takahashi Yosuke Takahashi Shigeki Takayama Ichiro Takeda Yohei Tan Nobukazu Tsukiji Kengo Tsushida Satoshi Uemori Taifeng Wang Santhos A. Wibowo Shu Wu Lin Xing Katsuyoshi Yagi Yoshihisa Yamada Kentarou Yamagishi Takahiro J. Yamaguchi Kazuya Yamamoto Yuji Yano Hajime Yokoo Fuminori Yui Yunpeng Zhang Feng Zhao Qiulin Zhu