Efficient Simulation of Power/Ground Networks with Package and Vias

As the number of metal layers and the frequency of VLSI continue to increase, the voltage droop on both the package and vias is becoming more pronounced. This paper analyzes the numerical problem encountered in simulation of power/ground networks together with C4 package and via model. A new preconditioned iterative method and associated acceleration technique are introduced to overcome shortages of previous methods. The new method not only is effective to speedup simulation without loosing any accuracy, but also extends the usage of preconditioned method to general circuit simulation using only a few additional memories due to its MNA formulation.