Foreword Special Issue on Analog Circuit Techniques and Related Topics

Abstract

Although it is said to be old-fashioned, analog circuit techniques have recently been receiving much attention. This is because a rapid growth of high frequency and/or high speed applications, low-power low-voltage applications etc. demands more and more sophisticated analog circuit design techniques, even in the digital circuits. Another aspect for this is that the mixed digital±analog design has become signi®cant in view of realizing system-on-a-chip concept. I believe that this special issue is a good chance to promote analog circuit techniques. The system-on-a-chip concept pushes the trend for high integration level of mixed analog-digital design. There naturally are arising needs for methodologies for estimating and reducing the substrate-coupled digital noises. I am very glad to be able to include two invited papers related to this timely subject. An invited paper by Dr. Czarnul et al. introduces systematic procedure to realize a fully balanced analog system from a single-ended analog system based on single-ended opamps, to combat with digital noise. Another invited paper by Dr. Nagata and Prof. Iwata addressed effective methods estimating the digital substrate coupling noise. Taking this opportunity, I would like to record here a history of this annual series of analog circuits and related topics initiated by Prof. Nobuo Fujii as the Guest Editor in 1993. Thanks to the succeeded Guest Editors, Prof. Keitaro Sekine (1994), Mr. Hisashi Yamada (1995), Dr. Minoru Nagata (1996), Prof. Atsushi Iwata (1997), and Prof. Yasuhiro Sugimoto (1998), this annual series has been well recognized among the analog circuit community and has established a ®rm ground. In fact, the Special Section has been reproduced in the Analog Integrated Circuits and Signal Processing, published by Kluwer Academic Publishers, since 1997. This year, the seventh series of the annual special section, 24 original contributions and two invited papers were submitted and 17 papers are published in this special section. These include data converters, computer aided designs, neural networks, wireless communication circuits, ®lters, sensor circuits, etc. On behalf of the editorial committee of this special issue, I would like to thank all the authors of submitted papers and 49 keen reviewers. As a Guest Editor, I am very grateful to all the committee members for their valuable efforts made in a very tight schedule, in particular, to the secretaries Mr. Tetsuro Itakura and Prof. Shigetaka Takagi.