Yoshihiro Nonaka
NEC
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Publication
Featured researches published by Yoshihiro Nonaka.
ieee international magnetics conference | 1999
Keishi Ohashi; Noboru Morita; Tadaaki Tsuda; Yoshihiro Nonaka
We examined the write performance of heads with a CoNiFe/NiFe composite write pole. The saturation induction B/sub s/ of the CoNiFe film was 2.1 T (21 kG). The CoNiFe layer thickness was typically 0.5-0.6 /spl mu/m, and the rest of the write pole was composed of Ni/sub 80/Fe/sub 20/. The dual high B/sub s/ layer structure with the CoNiFe films on both sides of the write gap gave excellent overwrite performance. It was over 30 dB for a medium that had a high coercivity of 560 kA/m (7.0 kOe).
SID Symposium Digest of Technical Papers | 2004
Yoshihiro Nonaka; Hiroshi Haga; Hiroshi Tsuchi; Youichi Kitagishi; Tadahiro Matsuzaki; Mitsuhiro Sugimoto; Hiroshi Hayama; Hideki Asada
A low-power 262k-color SOG (System-On-Glass) LCD has been developed for mobile applications. It is integrated with a DC-DC converter and driver circuits that contain 6- bit DACs, and it consumes less than 5 mW in operations with a single voltage power supply of 2.5 V.
ieee international magnetics conference | 2000
Yoshihiro Nonaka; Hiroaki Honjo; Tamaki Toba; Shinsaku Saito; Tsutomu Ishi; Mikiko Saito; Nobuyuki Ishiwata; Keishi Ohashi
We have developed a Co-Ni-Fe write head with a short yoke length for high-speed recording. By reducing the yoke length to 9.5 /spl mu/m, the eddy currents induced in a yoke with a relatively low resistivity (0.2 /spl mu//spl Omega/m) were reduced. The head of this short yoke had good write performance for a medium with a coercivity of 400 kA/m (5000 Oe) at frequencies up to 250 MHz (the overwrite less than -30 dB, and nonlinear transition shift less than 7%).
SID Symposium Digest of Technical Papers | 2003
Yoshihiro Nonaka; Hiroshi Tsuchi; Hiroshi Haga; Hideki Asada; Hiroshi Hayama; Naruaki Takada; Kenji Sera; Hiroyuki Uchida
A DC-DC converter composed of charge pumps and regulators has been integrated into a poly-Si TFT LCD that also contains a 6-bit DAC. It has the ability to supply regulated voltages to the 6-bit DAC and to the LCDs gate driver circuit.
ieee international magnetics conference | 1999
Tsutomu Ishi; Yoshihiro Nonaka; T. Matsubara; Nobuyuki Ishiwata
We have developed a focused ion beam trimmed write head using Al/sub 2/O/sub 3/ refilling, in which an Al/sub 2/O/sub 3/ film was deposited and a two-step lapping process was performed after FIB trimming at the air bearing surface. This process provided highly defined pole edges without any rounded corners, well-filled hollows, and a damage-free read element. Good environment-proof characteristics were also obtained, because a diamond-like carbon film was deposited as a protective layer on the element after FIB trimming. The fabricated head showed good overwrite characteristics in half-micron width writing.
SID Symposium Digest of Technical Papers | 2007
Hiroshi Haga; Yoshihiro Nonaka; Youichiro Kamon; Youich Kitagishi; Masayuki Jumonji; Kenichi Takatori; Hideki Asada
An SOG-LCD with integrated 230kb DRAM frame memory has been demonstrated. To achieve this dense integration, a memory system architecture for horizontal stripe was developed. Memory tests proved a 1MHz operation and retention time of 166ms. Fine images are displayed both in still images and moving pictures.
SID Symposium Digest of Technical Papers | 2005
Hiroshi Haga; Yoshihiro Nonaka; Youichi Kitagishi; Youichiro Kamon; Tadahiro Matsuzaki; Yoshinobu Sato; Hideki Asada; Tomohiko Otose; Daigo Sasaki
A system-on-glass (SOG) DRAM intended for integrated frame-memories of 262k-color QCIF+ displays has been developed. An integrated codec circuit reduces the number of memory cells and layout area by a factor of 2/3. By combining the SOG-DRAM, which has a data retention time of over 16.6 ms, with an embedded controller that enables simultaneous access for writing and reading, a frame-memory has been created. The operation was verified by chip measurement and demonstration.
SID Symposium Digest of Technical Papers | 2008
Yoshihiro Nonaka; Jiro Yanase; Hitoshi Yoshida; Kenichi Takatori; Koji Shigemura; Hideki Asada
A non-rectangular SOG-LCD has been developed by a well-polished system-integration technology including an arrangement in space. Driver circuits integrated along with curved sides of a heart-shaped screen with a hollow and an array of pixels slanting 45 degrees offer narrow bezels of less than 2 mm.
Archive | 2003
Yoshihiro Nonaka
Archive | 2000
Hiroaki Honjo; Nobuyuki Ishiwata; Tsutomu Ishi; Mikiko Saito; Shinsaku Saito; Tamaki Toba; Yoshihiro Nonaka