Modeling economics of LSI design and manufacturing for test design selection

Many test designs (or DFTs: designs-for-testability) have been proposed to overcome various issues around LSI testing. In this paper, we propose a cost and benefit model for comparing several test designs in terms of the final profit of logic LSI design and manufacturing. Test designs can affect chip area, testing time, test generation time and fault coverage; in the proposed model, we clarify the relationship among these factors for major three test designs: scan design, built-in self-test (BIST) design and test compression design. The proposed model reveals the final profit for each test design in a given LSI design and manufacturing environment, so that it can designate a suitable test design in the early stage of LSI design flow. We show an example of application of the proposed model for test design selection in a given environment.