Ibist interconnect and bridge fault detection scheme

Abstract

A method and mechanism for detecting interconnect and bridge defects. Contact points in a chip are assigned placement designation such that no two adjacent points have the same designation. A transmitter, receiver, and optional transmitter/receiver test are then run. During the transmitter test, transmitters with a given designation drive a particular test pattern while other transmitters drive a different test pattern. Receivers compare received test patterns against expected patterns. During a receiver test, transmitters drive a test pattern corresponding to the placement designation of the receivers to which they are coupled. During a particular receiver test, transmitters coupled to receivers of a given designation drive a particular stream, while other transmitters drive a different stream. Receivers then compare received streams against an expected stream. Finally, the placement designation of a transmitter or receiver of an adjacent transmitter/receiver pair may be temporarily assigned an alternate designation. A transmitter or receiver test is then run and receivers check received test patterns against expected patterns.