An efficient and economic partitioning approach for testability

Abstract

This paper presents an RT level partitioning approach for sequential circuits described as data path and control part. The data path of a circuit is partitioned at some hard-to-test points detected by an RT level testability analysis algorithm. These points are then made directly accessible by DFT techniques. The control part is also modified to control the circuit in normal mode and test mode. In the normal mode, the circuit is controlled to perform its function, while in the test mode, all partitions are controlled independently. As a result, test quality is improved by independent test generation and test application for every partition. The partitioning complexity is reduced by the use of testability analysis results and the area overhead is lower than that of full scan designs for most benchmarks we used. Experiments show results of the approach as compared with no scan, partial scan and full scan schemes.