Developing expert computer aided design systems] Developing expert CAD systems

The importance of CAD to electronics technology Computer-aided design (CAD) is one way of coping with the problem of how to design and build very complex systems. This problem is particularly acute in electronics technology. Designs are now (1984) said to be design-limited, rather than technology-limited. It can take months to generate a design for a chip, so that it might be obsolete before it can be manufactured. Manual design of large-scale integration (LSI) chips (circa 10,000 gates) is almost impossible. However, using current technology it is possible to produce chips having 250,000 gates. It is understandable, therefore, that there is great interest in improving existing CAD systems. Designers of CAD systems are concerned with formalizing and automating as much of the design task as possible. Automating design of any kind has long been acknowledged as a project fraught with intractable problems. A human designer has to have an understanding of the nature of the materials used in manufacture, a knowledge of common problems and well-tried solutions, and above all, creativity in producing new designs. Understanding, knowledge and creativity are three properties even the most artificially intelligent of computer programs have been entirely lacking in until very recently. Some people would deny computers these qualities entirely, on philosophical grounds (eg Dreyfus 1979; Searle 1981). There are few theories in cognitive psychology which can help. Front Matter....Pages 1-6 Introduction....Pages 7-11 What is CAD?....Pages 12-18 How is design carried out?....Pages 19-32 What makes a good CAD system?....Pages 33-44 Design representation....Pages 45-62 Techniques for electronics engineering from artificial intelligence....Pages 63-84 An ‘ideal’ CAD system....Pages 85-96 Summary....Pages 97-102 Back Matter....Pages 103-118