FFinder: A MAPLE-based CAD frame for identifying feedback loops in electric circuits

A MAPLE-based package for detecting feedback loops -positive and negative - has been developed. The tool accepts the circuit description either through a SPICE-like input file or via a schematic editor. The method for finding feedback loops is based on a slightly modified version of the well-known LU decomposition algorithm. In the paper, the idea behind this approach is explained by resorting to topology- based concepts of the LU decomposition. The tool delivers symbolic expressions of the transfer functions belonging to the feedback loops that are embedded in the circuit. These transfer functions can be used to establish ulterior design guidelines.