Johannes Adam received a doctorate in physics from University of Heidelberg, Germany, in 1989 on a thesis about numerical treatment of 3- dimensional radiation transport in moving astrophysical plasmas. He was then employed in software companies, mainly working on numerical simulations of electronics cooling at companies like Cisi Ingenierie S.A., Flomerics. Ltd. and Mentor Graphics Corp. In 2009 he founded ADAM Research and does work as a technical consultant for electronics developing companies and as a software developer. He is the author of a simulation program called TRM (Thermal Risk Management), designed for electronics developers and PCB designers who want to solve electro-thermal problems at the board level. He is a member of the German chapter of IPC (FED e.V.) and engages in its seminars about thermal topics. He is a Certified Interconnect Designer (CID). He is living in Leimen near Heidelberg.

## PCB Signal Traces Are Hotter Than We Think

In this article, Douglas Brooks and Johannes Adam illustrate how the thermal impacts of heated traces and pads are not limited to the board layer on which they exist; read on to see how they are reflected on every board layer above and below them.

## How Do Traces Fuse (Melt)?

What happens when you apply current to a trace? How long until disaster ensues? Douglas Brooks and Johannes Adam melted some boards, turned traces into flames, and applied some equations to shed some light on these questions.

## Internal Trace Temperatures; More Complicated Than We Think

It turns out that dielectrics, in fact, cool traces more efficiently than does convection + radiation, and therefore internal traces are relatively cooler. In this article, Brooks & Adam examine the question: Is there a predictable relationship between the external temperature of a trace and the internal temperature of the same trace carrying the same current?

## Current Density: Interesting, But Irrelevant

Current density can be an interesting concept. Graphics based on current density can be fascinating. But from a practical standpoint, current density is irrelevant. It is a consequence of other things, not a determinant of them. What follows will explain why.

## Vias Are Cooler Than We Think

The inescapable conclusion from the analysis presented here is that the conventional wisdom has been wrong! The current does not determine the temperature of the via. Find out what does.