Active Circuits With Diodes: Topological Conditions Sufficient to Determine the State of a Diode

Let N be a circuit composed of a finite number of positive and negative linear resistors, ideal diodes, nullators, norators and independent current and voltage sources. In this article, we consider the problem to determine, without any numerical computation, the state of a diode of N. We propose a set of topological conditions such that, when verified by a diode of N, the state of the diode is determined and the same in all the solutions of N. Our results may simplify, sometimes dramatically, the usual trial-and-error procedure to find the solutions of N.