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Comment by Osmium | Hacker News Reader

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Osmium·

> The fact that it's in a (gigantic by current standards) ceramic QFP would also suggest an aerospace application.

(For anyone else like myself who didn't know what a QFP was: https://en.wikipedia.org/wiki/Quad_Flat_Package )

Why does a ceramic QFP suggest an aerospace application?

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Essentially any time you see ceramic packages they are either US or Russian military where cost is not a consideration. Aerospace is very similar in their requirements for ruggedness and performance over temperature swings, so often end up using the same packed chips as the military rather than consumer level ones. Lots of early medical electronics like pacemakers seem to use military spec packages as well, presumably just because they are in a space where you can't really dig them out easily and replace some faulty consumer grade 74 series logic.

I think I saw some of those when I was working with guys who designed oilfield tools. It was always a challenge to find stuff with a decent MTBF in the 150C+ oilwell environment. IIRC, there was no published info on it, so we bought a ton of different brands and models, tested them all in-house, and built tools with the ones that performed the best.

Ceramic (vs plastic) is better suited for extended-temperature environments, which often implies aerospace or military.

There is some controversy here. In Russia all domestic chips authorized to be used in military equipment must be packaged in ceramic case. But the reasons for this lost in time when plastic packages were not good enough. These days it seems it is just a waste of money. In reality plastic packages offer some benefits for military applications over ceramic ones (like better G-shock/vibration resistance).

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