Corner models: Inaccurate at best, and it only gets worst …

Corner (best- and worst-case) models have been a mainstay of integrated circuit design for decades. Obviously they can be effective, especially for digital CMOS design. However, there are significant inaccuracies that arise when digital CMOS corner models are used for analog circuits, or any types of circuits or measures of circuit performance they were not targeted for. This paper details what corner models can and cannot do, and shows their inadequacies for analog CMOS circuits.