A bead probe CAD strategy for in-circuit test

Bead Probe Technology has been developed as alternative In-Circuit Test (ICT) contact points replacing conventional test pads normally integrated into a printed circuit layout [Park04], [Park05], [DoGr06], [Agil07]. This paper discusses the potential of using Bead Probes in Computer Aided Design (CAD) systems when getting a board ready for production. It outlines the requirements that a software package must address in order to incorporate Bead Probes into the board design process. Finally, a software package was developed to implement this process and evaluations were made on a number of circuit boards representing the industry sectors of communications, consumer electronics, military/aerospace and automotive. The evaluations provide insight into the ability of Bead Probes to enhance access, manage board stress, reduce cost and increase ICT test reliability.