DoD's increasing emphasis on reducing costs by adapting commercial business practices, coupled with parts obsolescence issues, has led to escalating interest in substituting commercial plastic-encapsulated microcircuits (PEMs) for "ML-SPEC" hermetically-sealed microcircuits (HSMs) in many programs. With a diminishing military market, fewer new microcircuits are being designed to operate over full military temperature ranges and the military procurement volume lacks the leverage for special process controls without adding cost (versus commercial users). While there is no direct DoD mandate for use of PEMs, many programs are moving ahead anyway. Lighter weight, smaller size, ready availability, and up to 80% lower cost are incentives for considering the use of PEMs. Continuing supplier improvements in PEM reliability, and qualification and use of PEMs in the automotive environment, which is similar to some military applications, have contributed to a significant number of PEMs already being used in selected military applications.
Numerous papers and articles have been published on the subject, based on studies, testing, and current experience. Finding so much information in circulation, this office has reviewed a representative selection of these papers by original equipment manufacturers (OEMs), PEM manufacturers, and selected military programs presently using PEMs (see SOURCES). This Technical Brief attempts to distill the key factors, while neither recommending nor discouraging the use of PEMs in military applications.
Updated Technical Briefs will be issued as more information becomes available. For assistance, see NAVY POINTS OF CONTACT.