OC Schooling: A Guide MOSFET Current Capabilities, by Buildzoid

Buildzoid is back from his adventures as a live stream commentator at the World Championship Final in Berlin, settling down to his regular Overclocking video cadence of, well… a few a week. Fresh off the production line we have superb and very comprehensive lesson in MOSFET current capabilities. The video goes through a complete description and analysis of what MOSFETs do, their role within a VRM design and ultimately why they fail at times.

The video begins with what an actual MOSFET IC is, describing how what we actually see on the PCB is in fact not the actual MOSFET but in reality ceramic casing that protects the MOSFET and allows it to dissipate heat more effectively. He also outlines the issues involved with measuring the temperatures of the silicon inside the chip. For most MOSFETS a Tjmax rating of 150 degrees C is the standard rating. Beyond this, you are in trouble.

However, even though it’s impossible to actually measure temperatures of the silicon inside the MOSFET, it is possible to basically extrapolate temperatures from using the temperature readings on the casing of the chip. Buildzoid actually goes in to a good level of detail, outlining concepts such as Conduction Heat Loss and Switching Heat Loss, plus lots of other stuff that is involved with truly understanding how a high-side MOSFET works within the VRM.

This video might well be above the pay grade for many overclockers but even if the technical details a little dense, it will definitely give you a thorough schooling into the deeper aspects of CPU and GPU power delivery.

You can find the video here on the Actually Hardcore Overclocking YouTube channel.


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