A Survey On Multilevel Router Considering Crosstalk And Timing Optimization

With the continuously development of VLSI sub-micron technology, the delay of interconnect and signal integrity have become the critical problem that affect the performance of chips.Compared with traditional routing strategies, high-order moments have to be considered when new routing strategies are designed to deal with more precise timing estimation and crosstalk optimization. The Elmore delay timing estimation model which was widely applied to traditional routing framework is actually the first order of circuit that has low precision for fast-transformed signal which has been proved. And the quality of waveform on nets can not reflected well only by first order moment of circuit.So recently moment-based global routing techniques have been concerned widely for performance driven routing.This thesis is based on a popular multilevel routing framework,and we design a multilevel router using the highly efficient symbolic moment calculation method (SMART algorithm) proposed recently.Using SMART,we could quickly get the high order moments of circuits based on which high order timing estimation model is applied to timing driven routing. At the same time, we use high order moments of circuits to do crosstalk optimization in the stage of global routing. The experimental result showed that our method get a good improvement on critical net timing budget and crosstalk optimization.