Learning Forum

[Kyle McNeil]

Hello,

I am using the Icepak Toolkit PCB model (Icepak > Toolkit > Geometry > PCB) in some PCB thermal models I am working on and I noticed that the "via material" Ansys creates to model a via array in a PCB has an anisotropic thermal condictivity. The axial thermal conductivity ("through the via array") seems to be calculated based on the provided PCB and via parameters. However, the radial thermal conductivity ("across the via array") seems to default to the thermal conductivity of whatever material is specified as the PCB substrate (in this case, FR4). This radial thermal conductivity does not seem accurate since in reality, it also depends on the copper weight, number of copper layers, fill factor of each copper layer, via diameter, via density and via filler material. Each of these parameters is specified for this Toolkit model but Ansys seems to make the radial thermal conductivity that of the substrate material regardless of what is specified for these other parameters.

Short of modelling the exact geometry of the PCB via array or importing a PCB .ODB file (not possible with student version), is there a way to more accurately model the radial thermal conductivity of a PCB via array in Ansys Icepak?          

[Pdev]

Hello Kyle,

Since you cannot import the .ODB file, we would recommend modeling the vias explicitly and ensure that it's meshed properly. 

Thank you.
Pdev