PREDUCTION/INTROFACE - Timing - page 1

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PREDUCTION/INTROFACE

It is customary to begin a topic of this sort with Deep and Noble Thoughts.
There are a number of excellent sources that convincingly make the point that
timing is extremely important in current and future technologies‚ and as a Bear
of Very Little Brain [Mil28]‚ the author has little to add to this. Therefore‚
all that there is to say is presented in a hybrid between a preface and an
introduction (which‚ in case you were wondering‚ is where the title of this
chapter came from). Suffice it to say that if you've picked up this topic‚ you're
probably interested in timing in one way or another.
This topic attempts to provide an overview of methods that are used for
the analysis and optimization of timing in digital integrated circuits in con-
temporary technologies. It is rather well known that this topic is important
to circuit designers and CAD engineers. The problem of timing analysis and
optimization has come a long way over the years‚ and has become increasingly
complicated with the passage of time due to two classes of effects that arise
due to shrinking device geometries:

“Micro” effects correspond to new physical effects at the device or intercon-
nect level caused by reductions in device dimensions.

“Macro” effects are related to problems of scale‚ as circuit sizes increase
with the ability to pack larger circuits on a die.