SYMBOLIC ANALYSIS OF LARGE ANALOG INTEGRATED-CIRCUITS - THE NUMERICALREFERENCE GENERATION PROBLEM

Symbolic analysis potentialities for gaining circuit insight and for e fficient repetitive evaluations have been limited by the exponential i ncrease of formula complexity with the circuit size. This drawback has begun to be solved by the introduction of simplification before and d uring generation techniques. An appropriate error control in both invo lves the generation of a numerical reference, which implies the calcul ation of network functions in the complex frequency variable. The poly nomial interpolation method, traditionally used for this task, is anal yzed in detail, its limitations for large circuit analysis are pointed out, and an adaptive scaling mechanism is proposed to meet the effici ency and accuracy requirements imposed by the new simplification metho dologies.