Yasuyuki Okuma

20 papers Journal 11Unranked 9
YearRankTypeTitle / Venue / Authors
2019 J jnl
Single-Chip 3072-Element-Channel Transceiver/128-Subarray-Channel 2-D Array IC With Analog RX and All-Digital TX Beamformer for Echocardiography.
IEEE J. Solid State Circuits
Yutaka Igarashi, Shinya Kajiyama, Yusaku Katsube, Takuma Nishimoto, Tatsuo Nakagawa, Yasuyuki Okuma, Yohei Nakamura, Takahide Terada, Taizo Yamawaki, Toru Yazaki, Yoshihiro Hayashi, Kazuhiro Amino, Takuya Kaneko, Hiroki Tanaka
2017 — conf
27.6 Single-chip 3072ch 2D array IC with RX analog and all-digital TX beamformer for 3D ultrasound imaging.
ISSCC
Yusaku Katsube, Shinya Kajiyama, Takuma Nishimoto, Tatsuo Nakagawa, Yasuyuki Okuma, Yohei Nakamura, Takahide Terada, Yutaka Igarashi, Taizo Yamawaki, Toru Yazaki, Yoshihiro Hayashi, Kazuhiro Amino, Takuya Kaneko, Hiroki Tanaka
2014 J jnl
A 0.6 V Input CCM/DCM Operating Digital Buck Converter in 40 nm CMOS.
IEEE J. Solid State Circuits
Xin Zhang, Po-Hung Chen, Yasuyuki Okuma, Koichi Ishida, Yoshikatsu Ryu, Kazunori Watanabe, Takayasu Sakurai, Makoto Takamiya
2013 — conf
A low voltage buck DC-DC converter using on-chip gate boost technique in 40nm CMOS.
ASP-DAC
Xin Zhang, Po-Hung Chen, Yoshikatsu Ryu, Koichi Ishida, Yasuyuki Okuma, Kazunori Watanabe, Takayasu Sakurai, Makoto Takamiya
2012 — conf
13% Power reduction in 16b integer unit in 40nm CMOS by adaptive power supply voltage control with parity-based error prediction and detection (PEPD) and fully integrated digital LDO.
ISSCC
Koji Hirairi, Yasuyuki Okuma, Hiroshi Fuketa, Tadashi Yasufuku, Makoto Takamiya, Masahiro Nomura, Hirofumi Shinohara, Takayasu Sakurai
2012 — conf
A 0.45-V input on-chip gate boosted (OGB) buck converter in 40-nm CMOS with more than 90% efficiency in load range from 2µW to 50µW.
VLSIC
Xin Zhang, Po-Hung Chen, Yoshikatsu Ryu, Koichi Ishida, Yasuyuki Okuma, Kazunori Watanabe, Takayasu Sakurai, Makoto Takamiya
2012 J jnl
A 1-V-Input Switched-Capacitor Voltage Converter With Voltage-Reference-Free Pulse-Density Modulation.
IEEE Trans. Circuits Syst. II Express Briefs
Xin Zhang, Yu Pu, Koichi Ishida, Yoshikatsu Ryu, Yasuyuki Okuma, Po-Hung Chen, Kazunori Watanabe, Takayasu Sakurai, Makoto Takamiya
2012 — conf
A 120-mV input, fully integrated dual-mode charge pump in 65-nm CMOS for thermoelectric energy harvester.
ASP-DAC
Po-Hung Chen, Koichi Ishida, Xin Zhang, Yasuyuki Okuma, Yoshikatsu Ryu, Makoto Takamiya, Takayasu Sakurai
2012 J jnl
An 80 mV Startup Dual-Mode Boost Converter by Charge-Pumped Pulse Generator and Threshold Voltage Tuned Oscillator With Hot Carrier Injection.
IEEE J. Solid State Circuits
Po-Hung Chen, Xin Zhang, Koichi Ishida, Yasuyuki Okuma, Yoshikatsu Ryu, Makoto Takamiya, Takayasu Sakurai
2012 J jnl
Startup Techniques for 95 mV Step-Up Converter by Capacitor Pass-On Scheme and V
IEEE J. Solid State Circuits
Po-Hung Chen, Koichi Ishida, Katsuyuki Ikeuchi, Xin Zhang, Kentaro Honda, Yasuyuki Okuma, Yoshikatsu Ryu, Makoto Takamiya, Takayasu Sakurai
2011 J jnl
0.18-V Input Charge Pump with Forward Body Bias to Startup Boost Converter for Energy Harvesting Applications.
IEICE Trans. Electron.
Po-Hung Chen, Koichi Ishida, Xin Zhang, Yasuyuki Okuma, Yoshikatsu Ryu, Makoto Takamiya, Takayasu Sakurai
2011 J jnl
0.5-V Input Digital Low-Dropout Regulator (LDO) with 98.7% Current Efficiency in 65 nm CMOS.
IEICE Trans. Electron.
Yasuyuki Okuma, Koichi Ishida, Yoshikatsu Ryu, Xin Zhang, Po-Hung Chen, Kazunori Watanabe, Makoto Takamiya, Takayasu Sakurai
2011 — conf
A 80-mV input, fast startup dual-mode boost converter with charge-pumped pulse generator for energy harvesting.
A-SSCC
Po-Hung Chen, Koichi Ishida, Xin Zhang, Yasuyuki Okuma, Yoshikatsu Ryu, Makoto Takamiya, Takayasu Sakurai
2011 — conf
A 95mV-startup step-up converter with Vth-tuned oscillator by fixed-charge programming and capacitor pass-on scheme.
ISSCC
Po-Hung Chen, Koichi Ishida, Katsuyuki Ikeuchi, Xin Zhang, Kentaro Honda, Yasuyuki Okuma, Yoshikatsu Ryu, Makoto Takamiya, Takayasu Sakurai
2011 J jnl
A Variable Output Voltage Switched-Capacitor DC-DC Converter with Pulse Density and Width Modulation (PDWM) for 57% Ripple Reduction at Low Output Voltage.
IEICE Trans. Electron.
Xin Zhang, Yu Pu, Koichi Ishida, Yoshikatsu Ryu, Yasuyuki Okuma, Po-Hung Chen, Takayasu Sakurai, Makoto Takamiya
2010 — conf
0.5-V input digital LDO with 98.7% current efficiency and 2.7-µA quiescent current in 65nm CMOS.
CICC
Yasuyuki Okuma, Koichi Ishida, Yoshikatsu Ryu, Xin Zhang, Po-Hung Chen, Kazunori Watanabe, Makoto Takamiya, Takayasu Sakurai
2010 J jnl
3-D System Integration of Processor and Multi-Stacked SRAMs Using Inductive-Coupling Link.
IEEE J. Solid State Circuits
Makoto Saen, Kenichi Osada, Yasuyuki Okuma, Kiichi Niitsu, Yasuhisa Shimazaki, Yasufumi Sugimori, Yoshinori Kohama, Kazutaka Kasuga, Itaru Nonomura, Naohiko Irie, Toshihiro Hattori, Atsushi Hasegawa, Tadahiro Kuroda
2008 J jnl
0.7-GHz-Bandwidth DS-UWB-IR System for Low-Power Wireless Communications.
IEICE Trans. Commun.
Ryosuke Fujiwara, Akira Maeki, Kenichi Mizugaki, Goichi Ono, Tatsuo Nakagawa, Takayasu Norimatsu, Masaru Kokubo, Masayuki Miyazaki, Yasuyuki Okuma, Miki Hayakawa, Shinsuke Kobayashi, Noboru Koshizuka, Ken Sakamura
2005 — conf
A novel UWB impulse-radio transmitter with all-digitally-controlled pulse generator.
ESSCIRC
Takayasu Norimatsu, Ryosuke Fujiwara, Masaru Kokubo, Masayuki Miyazaki, Yasuyuki Okuma, Miki Hayakawa, Shinsuke Kobayashi, Noboru Koshizuka, Ken Sakamura
2001 J jnl
Blind source separation and chaotic analysis of EEG for judgment of brain death.
Artif. Life Robotics
Gen Hori, Kazuyuki Aihara, Yoshikuni Mizuno, Yasuyuki Okuma