Component lifetime modelling

There are two approaches to component lifetime modelling. The first one uses a reliability prediction method as described in the (military) handbooks with the appropriate models and parameters. The advantages are: (a) It takes into account all possible failure mechanisms. (b) It is easy to use. The disadvantages are: (a) It assumes a constant failure rate which is often not the case (infant mortality). (b) It contains no designable parameters and therefore it cannot be used for built-in reliability. The second approach is to model the different degradation mechanisms and to incorporate this into an (existing) circuit simulator. Here we have also advantages and disadvantages which are mostly complementary to those of the first method.