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发表于 2007-1-24 08:38:19
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However, having said this, it is the hallmark of a good engineer to be aware
of all the aspects involved even though he or she may not need—or indeed, not
be able—to do anything about them. This text adopts this approach, and attempts
to give a comprehensive overview of all aspects of custom electronics, including
the very important but difficult managerial decisions of when or when not
to use it.
The concept of custom microelectronic circuits is not new; it has been
almost three decades since its simple conception, but it probably did not achieve
very great prominence until the early 1980s. The introduction of the microprocessor
as a readily available standard off-the-shelf part delayed the wider adoption
of custom microelectronics and still is a major force in all the initial ‘‘howshall-
we-make-it’’ product design decisions. Nevertheless, custom ICs offer their
particular technical or economic advantages, and every product designer should
be aware of the strengths as well as the weaknesses of both custom and other
design styles. These are the matters we shall consider in the pages of this text.
It is assumed that the reader will be familiar with the principles of microelectronic
devices, semiconductor physics, basic electronic circuits, and system
design as covered in many standard teaching texts. For readers requiring a more
detailed treatment than is given here, specific texts dealing solely with such areas
as device physics, computer-aided design, or other aspects, should be consulted.
Regrettably, no one book (and no one author!) can cover all these aspects in
depth, but it is hoped that the references contained in these pages will point to
such additional in-depth information.
The principles of custom microelectronics are now well established, but in
common with the whole of the microelectronics industry, there is a continual
evolution in complexity of devices, in obsolescence of particular components and
CAD resources, and in the rise and fall of industrial companies that make up the
custom circuits field. It is therefore inevitable that some of the commercial products
described in this text will no longer continue to represent the status quo, but
the basic educational points being made using these illustrations should remain
valid. It is therefore hoped that this book will enable readers to appreciate the
broad spectrum of custom microelectronics and will serve as an appropriate reference
to whatever newer products and design strategies evolve in this field.
Stanley L. Hurst
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