A built-in self-test method for write-only content addressable memories

Abstract

A novel and pragmatic built-in self test technique provides cost-effective and thorough testing and diagnosis of content addressable memories (CAMS). The method is particularly attractive for write-only CAMS, as neither the presence of a read port nor direct observability of CAM match-lines are required or testing. The underlying test algorithm uniquely exploits little known inherent properties of pseudorandom patterns generated by linear feedback shift registers in a test-time and hardware-efficient BIST implementation.