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Fumio ARAKAWA Motokazu OZAWA Osamu NISHII Toshihiro HATTORI Takeshi YOSHINAGA Tomoichi HAYASHI Yoshikazu KIYOSHIGE Takashi OKADA Masakazu NISHIBORI Tomoyuki KODAMA Tatsuya KAMEI Makoto ISHIKAWA
A SuperHTM embedded processor core implemented in a 130-nm CMOS process running at 400 MHz achieved 720 MIPS and 2.8 GFLOPS at a power of 250 mW in worst-case conditions. It has a dual-issue seven-stage pipeline architecture but maintains the 1.8 MIPS/MHz of the previous five-stage processor. The processor meets the requirements of a wide range of applications, and is suitable for digital appliances aimed at the consumer market, such as cellular phones, digital still/video cameras, and car navigation systems.
Ryoichi MIYAUCHI Akio YOSHIDA Shuya NAKANO Hiroki TAMURA Koichi TANNO Yutaka FUKUCHI Yukio KAWAMURA Yuki KODAMA Yuichi SEKIYA
This paper describes the Fractional-N All Digital Frequency Locked Loop (ADFLL) with Robustness for PVT variation and its application for the microcontroller unit. The conventional FLL is difficult to achieve the required specification by using the fine CMOS process. Especially, the conventional FLL has some problems such as unexpected operation and long lock time that are caused by PVT variation. To overcome these problems, we propose a new ADFLL which uses dynamic selecting digital filter coefficients. The proposed ADFLL was evaluatied through the HSPICE simulation and fabricating chips using a 0.13 µm CMOS process. From these results, we observed the proposed ADFLL has robustness for PVT variation by using dynamic selecting digital filter coefficient, and the lock time is improved up to 57%, clock jitter is 0.85 nsec.