Extended temperature microcontrollers ( 150o C - Operation )

150 C is ambient.


Regards, Dana.

Honeywell used to make an 8051-type uC that was
good to 225C. But (a) it's obsolete and (b) when it wasn't,
they wanted $877 a pop through Digi-Key. They do have
two in stock if you're that kind of desperate.

Nothing else that turns up in a >200C search is in stock
except for a 16/32-bit ARM product from TI (probably one
of the Vorago modified products)


Now I do know, from bouncing off the high temp market
a few times, that most of the serious down-hole instrument
people use automotive / MIL-B grade product which they
have personally characterized for suitability and durability,
because of the pricing I mention (commonly applied to
any product which falls outside mainstream high volume
test, or has a narrow end market, or in this case both).

In general an epi-on-P+-handle or a SOI product stands a
good chance of being useful well outside standard MIL
temp range. I have tested 5V flash ADCs on heavy-handle
JI and ported to silicon-on-sapphire substrates, and both
worked properly out to 300C (at which point, a few months
in, the Delta oven burned itself up and the experiment
was over). But no manufacturer has the infrastructure,
and almost none the experience or the patience (or the
business case) to try and qualify a 300C product with
years of service@temp reilability. Hell, 300C sockets are
hen's teeth, and accelerated testing needs higher....

Anyway it's highly likely that you've looked at some parts
which are indeed capable, but the mfr will not make that
claim because backing it up costs money and holds risk.

Proving lot-level reliability in production for 200C or 250C
is doable. As the only customer you'd be asked to pay
the whole NRE and wait a good long while. You might
end up getting a shorter lifetime guarantee (if you call
such forward looking statements, backed by an experiment
done years or decades ago, as guarantees) than you had
hoped. Science does what science does.

You might find HiTEC (High Temperature Electronics
Conference) publications which let slip, that kind of info.
Last one I went to was back in '93 I think but it's still
going on, annual or biennial, I believe. Even seeing who
is bothering to show up, might give you some leads who
you could hit up on LinkedIn or through author contact
info on the papers.

I wasn't aware that there are automotive grade microcontrollers suited for operation temperature above 150oC. Anyay, according to the datasheet of one I came across more than a decade ago (whose manufacturer even no longer exist), although it was characterized to operate at 200oC, its MTBF chart showed a derate of downto 1/10 of its estimated 20 years lifespan operating at 25oC, so there is no free lunch. Thank you all for the inputs, I will consider chosing an automotive one, instead of military.

If the customer is a US-domestic entity then you can get
the parts by just filling out a little paperwork, saying who
(and they sign up to be good little ITAR-complying boys
themselves).

Outside US shipments, those forms get to go to Commerce
or State, depending on product attributes. Anyone selling
rad hard or sole-purpose MIL parts will know the drill and
walk you through it in the interests of making the sale.

I'd stick with "dual use" and "space environment" parts.
You don't want the baggage of anything hard core,
like anything that's nuclear event survivable or operate-
through. But not to worry, if you found anything like that
you wouldn't want to pay the jacked-up unit price anyhow.
The meat of the market is in space anyway, as are all but
an infinitesmal fraction of RH product developments (major
military programs, on their own dime, at onshore foundries).

It's really pretty sad, it's well known how to make a decent
microcontroller for 250C on commercial foundry flows
(SOI) and there remain some SOI technologies / foundries
that would be perfectly suitable. And there are open sourced
8051 designs I believe (determining which, if any, are
"production grade" and "101% development system
compatible", would be on you).