Analog Design and Simulation Using OrCAD Capture and PSpice, 2nd Edition

Chapter 11

Worst Case Analysis

Abstract

Worst Case analysis is used to identify the most critical components which will affect circuit performance. Initially a sensitivity analysis is run on each individual component which has a tolerance assigned. The component value is effectively pushed toward both of its tolerance limits by a small percentage of its value to see which limit would have the most effect on the worst case output. A Worst Case analysis is then performed by setting all the component values to their end tolerance limits which gave an indication of the worst case results. In order to reduce the number of simulation runs, collating functions can be used to detect differences from the nominal worst case output such as minimum, maximum, ...