Checking multiple faults of combinational devices

The paper proposes a method and an algorithm for design of a test of multiple constant faults in combinational circuits built of any kind of elements. The algorithm leads to a test of length two to check the circuit line; for one output circuits this test will be obtained whenever it exists at all. The core of the method is the calculus of $D$-cubes [1,2]. A formal tool which permits avoiding compensation of a fault in the line to be checked is introduced.