Recent content by Solid-Statist

From a relative standpoint, how much do "low-power" LEDs differ from high-power LEDs in their maximum lumen- or power-density? The Plessey paper on LED Single-Die Solutions notes that this configuration has an advantage over "multi-junction die" in that there is no dimming or shadowing in the...

Let’s give this a shot… In the drawing, the high-power LED die is about 1/5th the length of the 7x7mm package, so the die length would be 1.4mm and its area about 2mm^2. The Plessey datasheet notes a power level of up to 15W for the device, so that would mean the maximum thermal load on the...

Yes, that methodology would work great to determine the state-of-the-art 'maximum lumen density' of LED technology. I don't (yet) know much about existing "typical die dimensions for some high power LED die", but know what to ask. Perhaps if I re-rephrase the questions: In high-power LED...

No doubt that would be true with conventional LED packaging. This was just a theoretical question. Perhaps if it's rephrased... Assuming that you have a tank of liquid nitrogen (or cooling equiv) to keep the LED die temp at/below its maximum limit ... what is the maximum density of...

Light-emitting diodes (LEDs) are replacing traditional lighting technology -- such as halogen -- in high-power lamps, as LEDs are much more efficient (Lumens/W) and longer-lasting. A commercial example of high-power LED flood lights: High Power 3000W LED Flood Light - Lsleds NOTE: The above...

Excellent feedback, thanks! This sounds like what I recall as 'pulse testing', seeing it done years ago with a TO-220 device to compare the relative cooling performance of various thermal-interface materials (TIMs). Using keywords from your response, I was able to locate this 2006 primer on...

Since CPU subassemblies have had built-in silicon temperature sensors / thermo diode monitors for years -- see below the ‘Core Temp’ report on my cheesy laptop’s CPU – as an on/off switch for its cooling fan, I guess that I assumed that this temp-sensing technology might be common in other...

In characterizing traditional discrete power devices, like TO-220s, manufacturers generally provide a thermal resistance from the junction-to-case (θJC, oC/W), so that users can calculate its expected temperature rise for a given power load...

Q: Is automobile engine horsepower calculated or measured? I do know that there's lots of calculation methodology for thermal modeling, but also understand that there are loads of uncertainties there. With thin thermal-interface materials (TIMs), by far the most reliable thermal-performance...

From what I understand, you can't beat sputter deposition for consistent ultra-thin coatings... https://en.wikipedia.org/wiki/Sputter_deposition ...assuming your coating can indeed be 'sputtered', of course. What type of coating are you using?

Sorry, I'm not a packaging engineer ... and I got that stack-up schematic from a colleague who is also not a packaging engineer. And, yes, FR4 is absolutely horrible for thermal dissipation, compared to ceramic, etc. I just wanted to show a simplified internal stack-up for, say, maybe a...

High-power electronic subassemblies – housing CPU or power-conversion semiconductors, for instance – require significant thermal dissipation to keep their chip-junction temperatures at or below their maximum operating temperature. (As a rule-of-thumb, every 10oC increase in junction temperature...

Well, it's certain nice to have found this forum! From puttering around the website, I see that there's plenty of expertise in lots of technical fields, even some where I already have some experience. For instance, there's discussion about high-energy physics and particle accelerators ...

I'd like to understand more about the requirements of electronic packaging, and how those are evolving to meet the demands of ever-greater performance. My education was in Chemical Engineering, and my professional background is in high-performance polymers for electrical/electronic insulation...