New Gate Models for Gate-Level Delay Calculation under Crosstalk Effects

Abstract

As the semiconductor feature size decreases, the crosstalk due to the capacitive coupling of interconnects influences signal propagation delay more seriously. Moreover, the increase of the operating frequency further emphasizes the necessity of more accurate timing analysis. In this paper, we propose new gate models to calculate gate output waveforms under crosstalk effects, which can be used for gate-level delay estimation. We classify the operation modes of metal-oxide-semiconductor (MOS) devices of a gate into 3 regions, and then develop simple linear models for each region. In addition, we present a non-iterative gate modeling method that is more efficient than previous iterative methods. In the experiments, the proposed method exhibits a maximum error of 10.70% and an average error of 2.63% when it computes the 50% delays of two or three complementary MOS (CMOS) inverters driving parallel wires. In comparison, the existing method has a maximum error of 25.94% and all average error of 3.62% under these conditions.