Electronics are small and getting smaller. The world in which we live is tending to stay at the same size. The one thing that typifies electronic thermal simulation models is the disparity of length scale that has to be accommodated. FloTHERM has been evolved to handle this disparity for over 20 years.  I, my fellow FloTHERM apostles and hopefully the FloTHERM userbase … [Read more...]

This series, despite being somewhat lengthy, is by no means a complete overview of the various methods, options and approaches to predicting component temperatures. Here is some stuff I didn’t cover… My bias in this series is towards the prediction of component temperature via simulation using a 3D CFD approach adopted in our (as ever) market leading FloTHERM and … [Read more...]

On the sliding scale of thermal component model representation king of all is a ‘detailed’ model. A 3D definition of all of the internal construction geometry and material properties does away with any of the accuracy inconsistency issues associated with the derived CTM (thermal resistor network type) approach. Despite the fact that all models are wrong a detailed … [Read more...]

Like a river this blog series is slowing down due to its increased width and depth, that and a lot of travel on my part. So, let’s get it back on track! The previous blog focussed on the relatively well known 2 resistor compact thermal model (CTM) method, its strengths (simple to measure and describe) and its deficiencies (unconfirmed and inconsistent accuracy for … [Read more...]

Next stop on the avenue of package thermal modelling is 2 resistor CTMs (compact thermal models). Specifically Theta_jb and Theta_jc, the thermal resistance between junction and board and junction and case respectively. Unlike their lowly 1R cousins these two resistances do not purport to include the effects of the package environment (well almost not) as such they should in … [Read more...]