Overview of SPICE-like circuit simulation algorithms

摘要

A tutorially orientated account of the principles underlyingncircuit level simulation forms the basis for discussing reliability ofncircuit level simulation. An outline of equation formulation and timendiscretisation of the equations is followed by consideration ofnstability of the numerical integration methods. The precision ofnsimulation, which also depends on the integration methods used, is thenndiscussed, with particular reference to the analysis parameters of thenSPICE simulator. A descriptive account of the Newton-Raphson method ofnsolving the nonlinear algebraic equations, derived from the discretisedndifferential equations, is then presented again with relation to SPICEnparameters. The reasons for convergence failure in both transient and DCnsimulation are related to the underlying principles of simulation andnpossible ill conditioning of the circuit. The paper includes some simplensimulation examples of problematic situations