Concurrent Testing of Multiple Cores Based on Test Vectors Compression

A concurrent test method for multiple cores is presented.Firstly,test sets of cores are merged. It combines overlapping test vectors to reduce the number of test vectors and test application time is decreased consequently.Test vectors are broad casted by bus to implement concurrent test in the test process. Then compatible compression of multiple scan chains and the distance-marking method are used to compress test data.The width of test set is decreased regularly after compatible compression of multiple scan chains and the distance-marking method can further compress test data efficiently. The approach achieves high compression ratio and reduces test application time.Compared to other concurrent test schemes,it has outstanding advantages such as easy test control procedure and low hardware overheads.