Printed circuits--Design and construction

Simulations of bending and twisting of surface mounted assemblies have been performed using the hybrid analytical/experimental analysis approaches, and the results are presented. Analytical analyses were combined with experimental load-deformation characteristics of the surface mounted assemblies to predict the maximum allowable loadings and deflections that surface mounted assemblies can withstand before incurring failures. Simulation results obtained were in close agreement with the real loading situations.

A formulation with its computer code based on the method of moments for thin wire structures is used for modeling the radiated fields emanated from a multilayer PCB. The moment method modeling technique proves to be a valuable tool for EMI prediction in a PCB at radio frequencies as well as useful design technique for obtaining the PCB layout which produces the least amount of radiation. A new modeling of the current distribution which includes the effect of microstrip open-end and bend discontinuities is used. The new modeling increases the accuracy of the prediction model for calculating the radiated EMI. The applicability of the moment method technique for studying the current distribution of wide microstrip is shown by modeling the existence of longitudinal and transverse currents at bend discontinuities.