Symbolic Techniques For Band Width And Phase Margin Optimization In Analog Integrated Circuit Design

Since most analog circuit simulation tools are based on numerical analysis method, the whole calculation process must be re-implemented and the circuit behavior is difficult to predict when the parameters change. This paper introduces a new algorithm based on GRASS (Graph Reduction Analog Symbolic Simulator), which not only extracts both band width and phase margin symbolically, but also finds a reasonable method to approximate these circuit performances. Combining with the symbolic sensitivity analysis, we can make a great contribution to symbolic band width and phase margin automatic optimization.Compared with traditional numerical methods, the new symbolic technique takes full advantage of intelligible graph operation and has the ability to adjust the circuit performance conveniently.