Optimal Wire-Sizing Formula Under the Elmore Delay Model
نویسندگان
چکیده
In this paper, we consider non-uniform wire-sizing. Given a wire segment of length L, let f(x) be the width of the wire at position x, 0 x L. We show that the optimal wire-sizing function that minimizes the Elmore delay through the wire is f(x) = ae ?bx , where a > 0 and b > 0 are constants that can be computed in O(1) time. In the case where lower bound (L > 0) and upper bound (U > 0) on the wire widths are given, we show that the optimal wire-sizing function f(x) is a truncated version of ae ?bx that can also be determined in O(1) time. Our wire-sizing formula can be iteratively applied to optimally size the wire segments in a routing tree.
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