This paper presents a march-like test T(AC-P) to cover comparison faults of ternary content addressable memories (TCAMs) with asymmetric cells. The T(AC-P) only requires 4N Write operations and (3N + 2B) Compare operations for an N x B-bit TCAM with Hit and priority address encoder outputs. We show that the test also can cover search time failures induced by process variation in the comparison circuit of a TCAM. Furthermore, a test T(MF) for match failures induced by the process variation in the comparison circuit of a TCAM is also presented.
IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS