Variability analysis and design of an integrated circuit using sensitivity information

A variability analysis of the open-loop DC gain G of an operational amplifier is carried out. DC sensitivities are used in the analysis, making the method economic compared to a Monte Carlo analysis. A novel way of using these sensitivities suggests choices for component matching in the integrated circuit, so as to reduce the variability of G. The analysis leads to a revision of the test limits of the gain. A 250-sample Monte Carlo analysis was used to confirm the results.