Patent Document ID: 20130226544
Application ID: 13881866
Patent Flag: 0

Claim One:
1. A non-transitory, tangible computer-readable medium having recorded thereon instructions for execution by a computer to carry out a method to identify rare-event failures of an electrical circuit design (ECD), the ECD having associated thereto process variables and performance metrics, the performance metrics being dependent on the process variables, the process variables having a probability distribution, the method comprising: generating a set of points from the probability distribution of the process variables; selecting a subset of points from the set of points; simulating the ECD for each point of the subset of points, to obtain simulation data; in accordance with the simulation data, calculating a value of a performance metric for each point of the subset of points, to obtain a set of performance metric values, the performance metric having associated thereto a target value; in accordance with the set of performance metric values and with the values of the process variables for each point of the subset of points, building a model of the performance metric as a function of the process variables; in accordance with the model, ordering remaining points of the set of points, to obtain ordered remaining points, the ordered remaining points having an order associated thereto; and displaying a count of a number of ECD failures, to obtain a displayed count of ECD failures, by iteratively repeating the following actions a-d, in accordance with the order of the ordered remaining points, until a stop condition is met: (a) simulating an ordered remaining point to obtain simulation data of the ordered remaining point; (b) calculating, in accordance with the simulation data of the ordered remaining point, a value of the performance metric of the ordered remaining point; (c) comparing the value of the performance metric of the ordered remaining point to the target value; and, (d) if the value of the performance metric of the ordered remaining point does not meet the target value, augmenting the displayed count of ECD failures.