Patent ID: 7035782
Filing Date: 2006-04-25
Classification: G06F

Abstract:
1. A computer implemented method of simulating a circuit, the method comprising: defining a set of differential-algebraic equations of the circuit; defining a simulation time interval corresponding to the differential-algebraic equations; dividing the simulation time interval into time intervals, wherein the time intervals have corresponding polynomials for each time interval, wherein each polynomial is a portion of an approximation to a desired solution of the differential-algebraic equations; and applying a collocation method to discretize the differential-algebraic equations; wherein: the simulation time interval has M collocation points, and wherein M represents a highest degree of interpolating polynomials; determining a smoothness for each interval, increasing an order of a solution for an interval if it is smooth, and splitting the interval into at least two sub-intervals if the interval is not smooth; solving the differential-algebraic equations in each of the intervals wherein approximation to the desired solution of the differential-algebraic equations is wherein I u(t) represents a solution, u T