Power Grid Correction Using Sensitivity Analysis Under An Rc Model

Verifying an RC model of the power grid requires one to check if the steady state voltage drops on all the nodes of the grid do not exceed a certain threshold. We propose an approach to correct the grid, in case some voltage drops violate the threshold condition, by making minor changes to the original design. Previous work has been done in [1] on the DC model of the grid and this paper deals with the transient model. Rather than directly reducing the steady state voltage drops below the threshold we work on reducing the first time step voltage drops. The method uses current constraints proposed in [2] to find the first time step voltage drop whose distance to the corresponding threshold is the largest. It then tries to estimate it as a function of the metal widths on the grid. A non-linear optimization problem is then formulated and the required metal line width changes that reduce the first time step voltage drops by a sufficient amount are then determined. The reduction of the first time step voltage drop by that amount will make the steady state voltage drops of all the nodes less than the threshold.