A new approach to built-in self-testable datapath synthesis based on integer linear programming

The focus of high-level built-in self-test (BIST) synthesis is register ass ignment, which involves system register assignment, BIST register assignmen t, and interconnection assignment, To reduce the complexity involved in the assignment process, existing high-level BIST synthesis methods decouple th e three tasks and perform the tasks sequentially at the cost of global opti mality, They also try to achieve only one objective: minimizing either area overhead or test time, Hence, those methods do not render exploration of l arge design space, which may result in a local optimum. In this paper, we p ropose a new approach to the BIST data path synthesis based on integer line ar programming that performs the three register assignment tasks concurrent ly to yield optimal designs. In addition, our approach finds an optimal reg ister assignment for each k-test session. Therefore, it offers a range of d esigns with different figures of merit in area and test time. Our experimen tal results show that our method successfully synthesizes a BIST circuit fo r every k-test session for all six circuits experimented, All the BIST circ uits are better in area overhead than those generated by existing high-leve l BIST synthesis methods.