Optimization of Futurebus+backplane structures

Proper and reliable performance of a separable interconnect system based on a two-piece, contact-with-wipe type of connector is contingent on a complex set of factors including geometric and mechanical characteristics of the surrounding hardware. One important dependency is the stiffness of the backplane assembly. Excessive deflection can lead to inadequate connector mating and wipe with resultant opens or reliability problems. It can also result in excessive stress in the printed wire board structure. Backplane stiffness is considered as a function of three key parameters: printed wire board and 2-mm connector housing structure, loading forces generated in the module to backplane insertion process, and backplane edge support at the card cage attachment. The solution of this problem was ideally suited to finite element analysis. The model was validated by experimental deflection measurement. Agreement between the finite element analysis results and test data allowed optimization of the back plane stiffening structure at an early stage in the system design