Fast simulation of interconnects with nonlinear loads using woodbury´s formula

Fast interconnect simulation technique with SPICE level accuracy is presented in this paper. First, the nonlinear devices are separately expressed with the linear components in the Newton method. Using Woodbury´s formula, the LU decomposition of the Jacobian matrix the elements of which are composed of the linear elements is only once done and factorization of the full Jacobian matrix is not necessary at each step of the Newton iteration. Therefore, the cost of the proposed method becomes several times of the simulation in which the linear components are only included, when the number of nonlinear elements is much less than the linear components, which is typical situation for interconnect analysis. It is confirmed that the proposed method is more efficient than Berkeley SPICE.