| Circuit Analysis is the cornerstone for electronic circuit engineering. On the one hand it provides the keys to understand the mechanisms and factors underneath the circuit operation. On the other hand, designers use analysis to obtain models of the circuit behaviour, the basis on which this behaviour can be predicted. Symbolic network analysis can improve the insight into the behaviour of analog circuits, and therefore can accelerate the design process of these circuits.;In this work, some techniques have been developed to intend to relieve the designers of systematic tasks, taking advantage of their experience and letting them concentrate on creative issues. The contributions are based on algebraic methods to calculate the network function of the circuit, internally modeled in terms of nullors and passive elements, that is being analysed.;To reduce the computational complexity of the calculations required to obtain a given network function, a hierarchical analysis strategy has been implemented. The strategy consists in the partition of the circuits into blocks that are calculated separately, and the results appropriately combined to obtain the global result.;Given the exponential increase of the number of terms in the symbolic expressions with the number of elements in the circuit, two fully symbolic procedures for the simplification of large expressions are presented to improve the formula interpretation by designers. The first technique simplifies the expressions by discarding the terms that are considered negligible in comparison with the most relevant parameters of the circuit, according to some rules provided by the designer. The method is also capable of inferring new conditions from those given.;The second approximation method calculates an approximated network function when parasitic parameters are introduced into the analysis, while preserving the order in the variable s of the original function. Different levels of approximation are possible to tune the desired accuracy.;Finally, a kind of structural synthesis is provided, based on the transformation of the original nullor network in other(s) equivalent in some sense. The strategy is based on network properties such as the relocation of nullators and norators that preserves any network function.;All the strategies developed in this work have been implemented and incorporated to a general purpose symbolic tool for the analysis, synthesis and exploration of analog circuits named SALAD. |
