Novel techniques to solve sets of coupled differential equations with SPICE

The solution of sets of coupled differential equations using SPICE is treated. The equations are rearranged so that each of the variables appears as a current through a 1- Omega resistor, and the SPICE transient analysis option TRAN is used to invoke the DCTRAN module. This module performs the DC operating point analysis, the initial-condition of transient analysis, the DC transfer characteristic analysis, and the transient analysis. By initially invoking the subroutine LOAD, the linearized system of nodal equations for the specific iteration is constructed. Separate computation of the nonlinear devices' contribution to the Y matrix is carried out by the respective subroutines.<
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