This paper presents various approaches for testing cellular tree structures with a constant number of test vectors, that is, independent of the number of cells (size of the tree). The necessary and sufficient conditions which must be satisfied in the state table of a basic combinational cell for achieving C-testability and one-step C-testability in a homogeneous tree, are proved. The design modifications required to accomplish this objective in arbitrary cells, are discussed. It is proved that three additional rows and three additional columns are needed in the state table of a cell; the characteristics of the additional states are also analyzed. The complexity of the proposed testing process is quadratic with respect to the number of entries in the state table of a cell. Illustrative examples are also given
Constant testability of combinational cellular tree structures
SCIUTO, DONATELLA
1992-01-01
Abstract
This paper presents various approaches for testing cellular tree structures with a constant number of test vectors, that is, independent of the number of cells (size of the tree). The necessary and sufficient conditions which must be satisfied in the state table of a basic combinational cell for achieving C-testability and one-step C-testability in a homogeneous tree, are proved. The design modifications required to accomplish this objective in arbitrary cells, are discussed. It is proved that three additional rows and three additional columns are needed in the state table of a cell; the characteristics of the additional states are also analyzed. The complexity of the proposed testing process is quadratic with respect to the number of entries in the state table of a cell. Illustrative examples are also givenI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
