Adaptive Test With Test Escape Estimation for Mixed-Signal ICs

The standard approach in industry for post-manufacturing testing of mixed-signal circuits is to measure the performances that are included in the data sheet. Despite being accurate and straightforward, this approach involves a high test time since there are numerous performances that need to be measured sequentially by switching the circuit into different test configurations. Adaptive test is a new test paradigm that still adheres to the standard approach, but it adjusts it on-the-fly to the particularities of the circuit under test so as to better control test time and to achieve robust outlier detection. In this paper, we present an adaptive test flow for mixed-signal circuits that has comprehensive user-defined parameters to span the tradeoff between test time savings and fault coverage so as to select an advantageous point on the curve based on test economics. The flow also provides robust test escape risk estimation so as to add confidence to the test process. The proposed idea is demonstrated on a sizable production dataset from a large mixed-signal circuit.