Many of the designs I do these days go in fairly inhospitable places in and around combustion engines. Typically they're subject to shock and vibration, and most important of all, the ambient temperature is very high. The maximum operating temperature is a major selling point for some products; the higher it is, the more applications open up for it.
Normal 'industrial' grade components are rated to 85C, which is no use at all in my market segment. An increasing range of components are available with temperature ratings up to 125C, and these are the parts in my everyday toolbox. It's no major problem; I can get analogue parts, power management, microcontrollers and FPGAs all with 125C ratings off the shelf.
A much, much smaller range of components (op-amps, some PICs) are commercially available rated to 150C. Some discrete semiconductors are available with 175C ratings.
Suppose, though, that I really - and I mean really - need to design an electronic device that can run hotter.
Does anyone have any experience in designing embedded circuits that include significant processing, and which can function at (say) 175C? Or 200C? Or higher?
I'm well aware that I'm into the realms of custom aerospace devices here. I know it'll be expensive, and that's OK.
What I need is to know who can supply the common building blocks (analogue circuits, CPUs, FPGAs etc) with exceptionally high temperature ratings - or, alternatively, if such components simply don't exist, what companies actually do instead.
Really high temperature cables, connectors, PCB substrate materials etc would be handy to know about too, but the first priority is active semiconductors.
All advice, especially from people who have been involved in such projects first hand, gratefully received!