A unified approach to autonomous and nonautonomous models of circuit elements

Abstract

This paper proposes a unified approach to both autonomous models of circuit elements and nonautonomous models which contain nullator-norator pairs. The unification is based on voltage-controlled current sources as the only kind of element utilized in autonomous models. It is shown that nonautonomous models are special (limit) cases of autonomous ones as some transadmittances of these sources tend from one to infinity. A systematic approach to the creation of models which consist solely of voltage-controlled current sources and are based on multiport equations is presented and illustrated by examples. By replacing the sources with their unistor models and then by application of the known transformations to the resulting unistor graph, autonomous and nonautonomous unistor models of several basic circuit elements are obtained. Some of these models seem to be new.

A family of AC amplifiers for ultra‐low frequency operation

“…Topologies in Figure 3 contain two OAs and thus are susceptible to be transformed by swapping their output nodes. The transformation can be easily formulated resorting to the nullor concept 17,18 (an OA is basically the combination of a nullator plus a grounded norator) and making all possible pairings between nullators and norators. The transformation preserves the transfer function assuming ideal OAs.…”