Method for creating a characterized digital library for a digital circuit design

摘要

Embodiments of the present invention relate generally to the creation of characterized outputs for a digital cell based on an input circuit design and input parameters. These characterized outputs may then be used to create digital cell libraries. One embodiment relates to selecting values for the input parameters that result in a sufficiently accurate representation of a particular characterization of the digital cell. Another embodiment relates to selecting an appropriate subwindow (i.e. a window within a larger window defined by guaranteed success and guaranteed failure boundaries) used to determine characterized output values, such as constraint values. Yet another embodiment relates to a failure recovery method that may be applied when a selected window or subwindow results in an invalid window (i.e. a window that does not contain the actual output value being determined). The failure recovery method is therefore used to determine a valid window.