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Shelf life of assembled electronics

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Siwastaja:
For example, a cheap commodity microcontroller from ST, is guaranteed:
Data retention: 1 kcycle (2) at TA = 85 °C: 30 years
(https://www.st.com/resource/en/datasheet/stm32f401re.pdf page 87)

And if they guarantee the parts for 30 years at +85, it is obvious to the designer a shelf-life will never be a problem, actual problems start appearing long after 50 years, unless ST produces crap.

You get similar guarantees for all flash based microcontrollers. No one would buy a microcontroller if the flash was rated for 15 years at 25 degC.

harerod:

--- Quote from: AndyC_772 on December 01, 2022, 12:18:19 pm ---...
I've just been through, let's call it, a relevant experience. I decided to get back into photography after a few years' hiatus.
...

--- End quote ---

What a sobering report. Thanks for the heads-up. I wouldn't have expect this from Canon.
While everybody with enough dough goes mirrorless, I expected to use my DSLR gear for the next decade or so. 5DmkIV, 6DmkI, 700D, 600D, same 100-400mm as you, gave away an inexplicably broken 70-200mm F/4 (aha!). My better lenses are Tamron these days (among others, a 150-600mm G2, for the birds).
Have you checked the situation with independent repair shops? Can they get hold of, for lack of a better term, Chinese replacement parts?
Canon maintenance has always been expensive and Tamron Germany won't even touch my lenses, because I had the audacity to buy them (new) in Japan.

At any rate, your report should prove that investing in a mint condition camera equipment collection may have its hazards. :(

Kasper:
Siwastaja, you called bs on a comment about FW retention of 30-50 years.

Then you linked an MCU that is rated for 30 years.  Does that mean Berni's comment was not bs?  Or are you saying anyone that uses that is a "total moron"?

You originally said at least 50 years at elevated temp or you're a total moron.  I guess what you meant was "about" 50 years? 

You've used a comment about cycle life related to streaming video to support your argument.  Does FW typically get rewritten hundreds of times? 




Siwastaja:

--- Quote from: Kasper on December 01, 2022, 06:39:49 pm ---Siwastaja, you called bs on a comment about FW retention of 30-50 years.

--- End quote ---

Sorry for failing to quote the exact part - the claim that flash is becoming more and more unreliable and embedded devices "mask" this unreliability by ECC is BS - unless the designer puts the firmware on some random cheap SD card or similar unsuitable flash technology, which is, I think, moronic and a mistake.

The 30-50 year part of the comment is not BS IMHO.


--- Quote ---I guess what you meant was "about" 50 years?
--- End quote ---

Yes, thank you.


--- Quote ---You've used a comment about cycle life related to streaming video to support your argument.  Does FW typically get rewritten hundreds of times?

--- End quote ---

I commented about the attitude of ignoring such obvious issues, even when pointed out to the designer. It doesn't matter if the exact mechanisms is wear out by too many erase-write cycles (the video time shift example), or due to aging by choosing completely inappropriate flash technology when the right technology is right in the front of their eyes - in either case, designer failed to do their job. And for the firmware part, it's not rocket science, choosing a normal microcontroller gets you into the guaranteed 30-50 years retention. And now this is relevant to the OP - if the flash is guaranteed to 30 years at +85 degC and being written 1K times, actual retention at +25degC and 1 write (at production) is going to be significantly more, possibly 100 years.

Sorry for lowish-quality post which was argumentative for no reason. I really just wanted to comment about the ECC part since the higher-end MCUs which have the ECC at all, this ECC can be configured to generate a failure interrupt, where the failure can be logged and handled - quite the opposite of masking the "increasing unreliability" of flash.

Kasper:
Siwastaja, thank you for clarifying.  When you try to discredit people's posts, it's good to include a clear explanation. 

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