Symbolic Distortion Analysis

Abstract

In the previous chapter, the algorithmic aspects of the symbolic simulation of analog circuits have been presented. The basic concepts have been illustrated for the symbolic simulator ISAAC [GIE_89c]. All analyses, however, were restricted to AC characteristics of linear(ized) circuits. In this chapter, several important extensions to the basic techniques are discussed such as for the symbolic analysis of harmonic distortion in weakly nonlinear analog circuits. In section 5.2, the symbolic analysis of noise behavior is discussed, in which an output variable is calculated for multiple inputs at once. In section 5.3, the symbolic analysis of harmonic distortion in weakly nonlinear circuits is discussed. An efficient analysis method is presented and implementation details are provided. In section 5.4, some other topics are discussed such as the symbolic calculation of sensitivity functions and symbolic pole/zero extraction. Techniques for the hierarchical analysis of large networks are then proposed in section 5.5. These techniques allow to reduce the CPU time for larger circuits. Finally, concluding remarks are presented in section 5.6.