Limit parameters: the general solution of the worst-case problem for the linearized case [IC design]

The use of limit parameters to determine the manufacturability of an IC design is addressed. On the basis of a sensitivity analysis of the circuit, a realistic worst-case (e.g. 3σ) is estimated. For this value, limit-parameter sets are calculated for every objective. These parameter sets include correct variances and correlations for the transistor parameters, which are derived from measurements in the fabrication process. Since the method is based on a sensitivity analysis, the enormous effort of a Monte Carlo method can be avoided