Syndrome-Testable Design of Combinational Circuits

Classical testing of combinational circuits requires a list of the fault-free response of the circuit to the test set. For most practical circuits implemented today the large storage requirement for such a list makes such a test procedure very expensive. Moreover, the computational cost to generate the test set increases exponentially with the circuit size. In this paper we describe a method of designing combinational circuits in such a way that their test procedure will require the knowledge of only one characteristic of the fault-free circuit, called the syndrome. This solves the storage problem associated with the test procedure. The syndrome-test procedure does not require test vector generation, and thus the expensive stage of test generation and fault simulation is eliminated.