The presentation points out the current numerical and experimental possibilities for planning and checking of the climate reliability of electronic PCBAs. Aim of the calculation methods of electrochemical migration times must be the assistance of the pre-optimisation of PCBAs in the developmental phase and the reduction of the necessary testing effort in qualification. All in literature traceable calculation approaches seem to be obtained by statistical assessments of empirical service life data. A physical modeling of the problem is mostly not given. Therefore, it is not possible to make statements by specific parameter variations about a PCBA which is under development. A transfer of the calculations of a common PCBA onto the redevelopment appears to be connected with a high risk, as the fitting parameters of the equations are heavily product-specific. Small changes in the circuit design and the circuit layout or the exchange of components for the realisation of the same function change the climate security of a circuit fundamentally. Furthermore in many cases reliable field data are missing for the calculation of acceleration factors of the climatic stress to be expected.
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