Page 40 - Analog Circuit Design Art, Science, and Personalities

Part Two

What Is Analog Design?

Everyone knows analog design is different from other branches of electronics. But
just what is analog design? There’s no definitive answer in this section, but three
authors do offer insights that point the way toward an answer.
Bernard Gordon, president of Analogic Corporation, discusses a key part of analog
design-the requirement that designers be able to visualize and manipulate, both
on a conscious and unconscious level, the multiple factors and interrelationships
between those factors present in every analog design. As he notes, this is more an
art than a sciencc.
Digital electronics can be thought of as dealing with a world that‘s either black or
white (or 0/1 or true/false), with no fuzzy gray areas between those levels. Samuel
Wilensky tells how analog design is the art of working in those gray arcas, with
designers required to optimize a circuit by sacrificing one parameter so another can
he enhanced. He uses the evolution of the digital to analog converter to show how
advances in analog design come through intuition and “feel” as much as through
rigid application of fixed rules.
Maybe the best way to understand what analog design is all about would be to
“walk through” an analog design task. Jim Williams retraces William R. Hewlett’s
footsteps a half-century later and discover\ that. while the components may have
changed, the basic principles and philosophy are still intact.

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