A novel and efficient method for power pad placement optimization

In this paper, we propose a novel and efficient iterative method for pad placement optimization of power grid with flip chip technology. Power grid with optimized pad placement has less IR-drop values. We develop a new method to calculate new locations of all pads. Placing pads at the new locations reduces local IR-drop values. In order to reduce global IR-drop values, we develop a graph-based strategy to decide which pads are moved to the new locations. After each movement of the pads, a static IR-drop analysis is performed. We develop multigrid accelerated modified Simulated Annealing method (MG_SA) and compare it with the proposed method on a set of test cases. Experimental results show that the proposed method outperforms MG_SA with similar or less IR-drop values and much less runtime.