Improving structural coverage of functional tests with checkpoint signature computation

Automotive markets place stringent demands on manufacturing test quality and in-field system test quality to ensure near zero defective parts per million (DPPM) quality and meet strict ISO 26262 ASIL quality levels, respectively. Recent automotive SoC trends indicate increasing use of high-performance compute with heterogeneous IP integration in nanoscale technologies. As a result, functional tests are increasingly used to augment traditional structural tests for defect screening and performance closure in both manufacturing and in-field system test environment. This work presents design enhancements and fault-grading improvements to improve the quality of existing functional tests at the SoC level. We attempt to measure the quality improvement of functional tests by measuring the corresponding structural coverage improvement with the proposed enhancements and present the implementation results from an industrial design.