Integrated Circuit Electromagnetic Susceptibility Investigation - Phase 2. Package Effects Study

The purpose of the Integrated Circuit Electromagnetic Susceptibility Investigation is to provide detailed information which can be readily applied by electronic system designers in their task of eliminating electromagnetic vulnerability from military systems. In view of the availability of different package styles to the designer, it was deemed feasible that package differences might exist which could be easily exploited in providing extra system protection at relatively low cost. This part of the program was designed to briefly explore that possibility by comparing the measured susceptibilities of similar devices in each of the flat pack, DIP, and TO-5 types of packages. Loss measurements on specially fabricated short-circuited packages were performed with the conclusion that the loss of the packages was not significant. To compare reflection properties, susceptibilities of 7400 NAND gates in DIP and flat pack packages, and 741 op amps in TO-5 and flat pack packages were compared at four frequencies .22, .91, 3.0, and 5.6 GHz. The small differences that were found to exist depend on frequency such that the package which is slightly better at the low frequency end is slightly worse at the high frequency end. In any case, the added protection that might be available by proper choice between these package styles is not believed to be significant to the system hardening problem.