A Tool for Symbolic Analysis and Design of Analog Active Filters

Abstract

In this paper we introduce a tool for symbolic analysis and design of analog active filters. It has been developed in Mathematica. The tool can be used to draw circuit schematics, and to formulate and solve analysis and design equations. We present a closed-form solution for a design problem that would otherwise only be possible by numerical optimization or trial-and-error guessing and simulation. Illustrative examples are given to demonstrate filter design with minimization of the sensitivity, and optimization of element values to have prescribed values. I. Introduction Many excellent filter analysis and design software packages exist, but they often focus on one aspect of the design process. For example, Spice simulates the circuit using numerical methods and there are schematic capture programs that interface to Spice. But, these programs cannot perform symbolic analysis or circuit synthesis. Motivation for the development of a new software environment is to integrate filter anal...