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To my mentors, Professors Georges Salmer and Eugène Constant, who passed on to me their passion for research into semiconductor device physics
To Nadine, Hélène and Pierre
Series Editor
Robert Baptist
Neuro-inspired Information Processing
Alain Cappy
First published 2020 in Great Britain and the United States by ISTE Ltd and John Wiley & Sons, Inc.
Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms and licenses issued by the CLA. Enquiries concerning reproduction outside these terms should be sent to the publishers at the undermentioned address:
ISTE Ltd
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John Wiley & Sons, Inc.
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© ISTE Ltd 2020
The rights of Alain Cappy to be identified as the author of this work have been asserted by him in accordance with the Copyright, Designs and Patents Act 1988.
Library of Congress Control Number: 2019957598
British Library Cataloguing-in-Publication Data
A CIP record for this book is available from the British Library
ISBN 978-1-78630-472-8
Acknowledgments
I wish to thank my colleagues, Virginie Hoel, Christophe Loyez, François Danneville, Kevin Carpentier and Ilias Sourikopoulos, who have accompanied my work on neuro-inspired information processing. This book would not have been possible without our numerous discussions on this new research theme.
I would also like to thank Marie-Renée Friscourt for her diligent and efficient proofreading of the manuscript, and for the many insightful remarks made for the benefit of its improvement.
Introduction
The invention of the junction transistor in 1947 was undoubtedly the most significant innovation of the 20th Century, with our day-to-day lives coming to entirely depend on it. Since this date, which we will come back to later, the world has “gone digital”, with virtually all information processed in binary form by microprocessors.
In order to attain the digital world we know today, several steps were essential, such as the manufacture of the first integrated circuit in 1958. It soon became apparent that integrated circuits not only enabled the processing of analog signals, such as those used in radio, but also digital signals. Such digital circuits were used in the Apollo XI mission that led humankind onto the moon, on July 21, 1969. Astronauts only had very limited computing means at their disposal to achieve this spectacular feat. The flight controller was a machine that we might consider very basic by today’s standards. Composed of 2,800 integrated circuits, each comprising two three-input “NOR” gates, 2,048 words RAM1 and 38,000 words ROM2 for programs, it worked at a clock frequency of 80 kHz and weighed no more than 32 kg for 55 W power consumption.
The exploit was thus essentially based on “human” or “cortical” processing of information: processing power, too often advanced today, is not always the sine qua non condition for success!
In
