Optimisation of Analog Circuits with Spice 3f4

In the paper four approaches of upgrading analog circuits analysis tools (SPICE was used) with optimisation loops are compared. In the first approach the optimisation algorithm is coded in Mathematica, which calls SPICE for every circuit analysis. In the second approach the algorithm is coded in Nutmeg. (Nutmeg is an interpreter designed as a user interface for SPICE, but it has all properties of a programming language.) In the third approach the algorithm is again coded in Nutmeg, but all computation (for example computation of the cost function) is performed by extern programs. And finally in the fourth approach the optimisation algorithm is coded in C. We compared computation times of all different approaches with a constrained direct optimisation method on a simple circuit. It turned out that the approach through Mathematica is elegant, but hopelessly slow. Both approaches through Nutmeg are compact, but unfortunately Nutmeg yields numerous bugs. The best results were obtained with C programs.