Patent ID: 6636839
Filing Date: 2003-10-21
Classification: G06F

Abstract:
In a circuit simulation tool, a method for determining a periodic steady state output response of a circuit driven by a periodic input signal, the periodic steady state output response covering a plurality of timepoints that span a period of the periodic input signal, the plurality of timepoints including a last timepoint, the method comprising:using a finite-difference method to form a non-linear system of equations for the periodic steady state output response of the circuit; solving the non-linear system of equations via a Newton iterative method to produce the periodic steady state output response of the circuit, each iteration of the Newton method associated with a respective linear system of equations; for each iteration of the Newton method, using a matrix-implicit iterative technique to solve for nodal voltages of the circuit at a particular one of the timepoints, the nodal voltages satisfying the respective linear system of equations associated with the iteration of the Newton method, wherein use of the matrix-implicit iterative technique avoids computation of a matrix to produce a solution of the respective linear system of equations; and providing the periodic steady state output response to the circuit simulation tool.