Symbolic simulation for efficient repetitive analysis and artificial intelligence techniques in CAD

An overview is presented of the symbolic approach for circuit simulation, and its two main application areas are described: (1) fast repetitive analysis, such as is needed for statistical analysis, and optimization, and (2) circuit design assisted by artificial intelligence and related techniques, such as is needed for new circuit architecture investigation. Two dedicated fully symbolic simulators for implementing this symbolic approach are described: SCYMBAL, a simulator for switched-capacitor circuits (SCNs) and the first published of its kind, and SYBILIN, a simulator for analog microwave circuits. To illustrate the capabilities offered to designers by these symbolic simulators, practical design tasks, carried out with the help of SCYMBAL and SYBILIN in the domains of computer intensive repetitive analysis and automated architecture generation and optimization, are presented