Calculating the effective capacitance for the RC interconnect in VDSM technologies

In this paper, we present a new technique for calculating an effective capacitance of an RC interconnect line in very deep submicron design technologies. The calculation scheme guarantees that the effective capacitance model simultaneously matches both the 50% propagation delay and the 0-to-0.8Vdd output transition behavior of a standard cell driving an RC interconnect. Experimental results show that the new technique exhibits high accuracy (less than 5% error) and high efficiency (converges in two or at most three iterations). The paper also includes extensions to handle complex cells as drivers of the RC interconnect.

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