On the decreasing significance of large standard cells in technology mapping

ABSTRACT

Technology scaling reduces gate delays while wire delays may increase. Our work studies the interaction of this phenomenon with technology mapping and its impact on modern EDA flows. In particular, we demonstrate that the use of larger standard cells increases the number of long wires and may undermine circuit delay optimization at 65nm and below. Experiments with 130nm, 90nm, 65nm, and 45nm industrial CMOS technology suggest that limiting the use of larger standard cells in technology mapping becomes more effective at 65nm and 45nm node, resulting in up to 12% improvement in critical path delay on large benchmark circuits.

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