Using thermal analysis to enhance fault isolation techniques

The present methods of diagnostic testing for printed circuit boards (PCB) using automatic test equipment (ATE) presents the Navy with technical and cost of ownership concerns. These concerns are manifested in several areas: (1) the escalating complexity of PCBs requires an ever-increasing amount of maintenance processing time, (2) the increased processing time results in escalating repair costs, and (3) protracted component turnaround-times are usually managed by procuring additional spares to meet operational requirements. When coupled with current PCB design constraints such as limited test points, in many cases ATE software that cannot isolate a fault to an acceptable ambiguity level, and a maintenance philosophy that places high reliance on ATE and less on the technical skills of maintenance personnel, the situation becomes bleaker. Naval Aviation cannot continue to absorb the increasing costs of ownership associated with current maintenance practices. Neither can it afford to make major changes in its current maintenance philosophy. The solution to this dilemma rests in the ability to successfully challenge the current ATE diagnostic testing methodology and develop a means of enhancing existing ATE capabilities.