Improved random walk algorithm for power supply noise analysis

Switching noise on power grid has been regarded as a serious problem in VLSI circuits. This paper thus focused on switching noise analysis on power grids. The power grid was modeled as a linear time invariant distributed RLC network and switching noise as time-varying current source. Instead of using direct methods to solve the network equations, an efficient approach based on random walk techniques was developed to simulate the voltage fluctuation caused by simultaneous switching activities. Two strategies were introduced to speed up the simulation process as well. The experimental results show that the proposed approach has the capability to analyze large power grids and is faster than SPICE analyzer.