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From: Don Y <blockedofcourse@foo.invalid>
Newsgroups: sci.electronics.design
Subject: Re: Operating temperature derating
Date: Thu, 13 Jun 2024 18:13:01 -0700
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On 6/13/2024 4:51 AM, legg wrote:

>>> What's your actual problem?
>>
>> If I have a device that claims an operating (or storage) temperature range
>> of [X,Y] what is the ACTUAL operating range LIKELY *designed* into the device.

> I think, at this stage, you're just being fractious.

And I think you're just unable to answer the question.  Don't feel bad;
I've asked this in two other places and have been met with similar
<mumbly> answers.  No one seems to design "consumer kit" so there are no
REAL processes to describe.  Commercial and Industrial designs are
handled much differently and more formally.

But, what the question HAS done is piqued interest in the *specifics*
of various bits of consumer kit; so, lots of examples of specific devices
with:
- UNspecified operating limits
- "fantasy" operating limits,
- limits that obviously have HUGE margins (e.g., the phone examples)
- *seemingly* well thought out limits (inferred by the wider range of
   operating conditions that obviously exceed the sorts of conditions
   they would likely experience... "temperatures never encountered on earth").

It seems like folks have suddenly become aware that they *don't* know
what the bits of kit that they've purchased CAN do and are now taking an
active interest in those figures.

It's educational to see which types of devices fit in each category as well
as which manufacturers.

But, still doesn't answer the question posed (as none of the designers
of these items are apparently available to shed specific light on their
design process/criteria)

> I'm out of here.