Sensitivity of embedded component temperature to PCB structure and heat transfer coefficient

The sensitivity of embedded component temperature to the location of an embedded copper ground plane is investigated using computer simulation. The results show that the presence of a copper ground plane in close proximity to a component layer improves the potential packing density of components within the layer. Furthermore, placing a copper ground plane between two signal layers can reduce thermal interaction between components in the two layers by a factor of up 10. The layer density within a multilayer PCB is therefore improved, which again leads to a higher packing density of components. Using the results generated by the simulation, the authors then proceed to investigate the sensitivity of embedded resistor temperature to resistor size under different conditions of surface heat transfer. The results show that large embedded resistors are more sensitive to surface heat transfer than smaller ones and that small components are more effectively cooled by placing embedded copper ground planes in close proximity to them.