Automatic Simplified Symbolic Analysis of Analog Circuits Using Modified Nodal Analysis and Genetic Algorithm

In this paper, a hybrid methodology based on modified nodal analysis (MNA) and genetic algorithm (GA) is presented for simplified symbolic small-signal analysis of analog circuits containing semiconductor devices like MOSFETs. At first, the circuit is analyzed by the MNA, and the derived exact continuous-time transfer function is automatically simplified via GA. We propose a new multi-objective criterion for symbolic simplification of continuous-time transfer functions, which can be performed by such optimization algorithms as local-search algorithms, heuristic algorithms, swarm-intelligence algorithms, etc. In this paper, GA is used to validate the proposed simplification criterion. All processes including netlist text pre-processing, symbolic analysis via MNA, post-processing, and simplification via GA are consecutively run in an m-file MATLAB program. The comparison of obtained numeric results with HSPICE demonstrates the efficiency of the proposed methodology.