Knowledge based extension of DIADES system for the analysis and synthesis of TGC circuits

A new and uniform approach to the computer-aided analysis and synthesis of analog circuits is presented. The system is specialized for transconductance-grounded capacitance circuits (TGC). The analysis is a transformation from a signal flow graph (SFG) to a transfer function (TF). It is based on a step-by-step transformation from SFG to TF by reductions of nodes: summation, multiplication, and feedback. Symbol manipulation of multivariate rational functions is used. The synthesis is a process of transforming a LC-ladder filter SFG to a TGC circuit. Heuristic synthesis procedures, inverse to the ones used in the analysis, search the solution space of equivalent SFGs and are theoretically able to find the optimal solution. The synthesis method includes three stages: SFG labeling, synthesis of the SFG branch transfer functions, and SFG repolarization. The application of some synthesis rules is illustrated on examples