Analog Circuit Simulation:Formulation of the Circuit Equations

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Formulation of the Circuit Equations

In SPICE, the circuits are represented by a system of ordinary differential equations. These equations are then solved using several different numerical techniques. The equations are constructed using Kirchoff ’s voltage and current laws. The first system of equations pertains to the currents flowing into each node. One equation is written for each node in the circuit (except for the ground node), so the following

Analog Circuit Simulation-0120

In this example, G and Q are simple linear terms; however, in general, they can be non-linear functions of the voltage vector V.

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