Scan Based Tests via Standard Interfaces

In state-of-the-art automotive controllers, test in the field cannot use features dedicated to production test. However, the enhanced testability by access to features such as scan-chains can increase the effectivity and the diagnostic features of tests in the field significantly. Therefore, an appropriate test access to the integrated test-technology is required. In this paper, we describe the possibilities and limitations of in-field access to embedded scan-test via high-speed standard interfaces. By use of such common interfaces for the test of integrated circuits, it should be possible to run test routines, e.g. for a complete automotive control unit, which includes functional tests as well as structure-oriented tests, in the field.