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Post the worst datasheet lies you've caught
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berke:

--- Quote from: joeqsmith on January 02, 2024, 05:27:07 pm ---From my experience, the story normally goes something like, I find a problem.  Contact company.  Company states I am an idiot and they can't replicate....

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--- Quote from: srb1954 on January 03, 2024, 01:35:42 am ---They refunded our money for the bad chips but we were still out of pocket for the engineering time lost investigating their bad chips.

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--- Quote from: David Hess on January 03, 2024, 03:26:03 am ---So we designed and built new boards with this improved converter and ... it still reported positive and negative zero.  We contacted Texas Instruments and confirmed our results, but as far as I know, they never changed the datasheets and never advertised the problem.

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A pattern seems to be emerging.

1. Find issue
2. Triple-confirm, have someone else look over it and prepare nice write-up with data
3. Send mini-report to manufacturer.  To customers this kind of report would be sent with a five-digit invoice, but for the gods of big IC this is an offering.  Secretly expect a handwritten thanks note from the CTO and a box of Champagne within a week.
4. Instead, quickly get a very short response from illiterate tech support with the equivalent of "Have you tried turning it on and off?".
5. Manage to write a polite response, include supplementary material.
6. Level 1 support recognizes a difficult customer and transfers the request to a less incompetent team.
7. Get response from higher-level tech support team, asking for clarifications (which of course were already included in the first two exchanges)
8. Re-send data highlighting the relevant parts, include cartoonish drawing making situation clear to even 5 year olds ("Bob is a transistor.  Where does it hurt, Bob?  Bob: I'm too hot.  Daddy said my collector can take lots of electricity.")
9. Two months pass.
10. "After totally unprompted investigations which are a regular part of our ISO9001 quality assurance program, our engineering team has determined that some batches of product XYZ were found to exhibit slightly degraded performance characteristics under very particular circumstances where no customers are likely to try to use them, and if they do they're probably of the annoying kind and they won't be getting free samples anymore."
11. Datasheet revision B, footnote 7. "Performance not guaranteed if device operated beyond typical parameters."
SeanB:

--- Quote from: joeqsmith on January 03, 2024, 06:02:23 am ---
--- Quote from: vk6zgo on January 02, 2024, 11:38:30 pm ---I've moaned on this forum before about the 4000 series monostables we used at my old work in ...

It's too long ago to remember the exact type number, but we used the devices to provide a quite long time delay,...

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Funny, we also used some of these old 4000 series CMOS parts for timers as well in the minute range.   buffered, unbuffered, brand, all made a difference for leakage.  We were pretty limited what we could use.  Seems like we found Motorola UBCP worked well.   We didn't want to pay extra for the higher temp parts and qualified with the cheapest.   Most parameters we didn't care about.   The caps were also a problem.    Cheap, crap design but worked alright.     

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And I would bet the manufacturer was unconcerned, as they all were within the maximum leakage range, just that none would ever be in the "typical" part of the range at all. Those all were pulled off for the industrial part line, not the commercial line.
Siwastaja:

--- Quote from: tom66 on January 02, 2024, 03:05:12 pm ---In the errata, there was this gem:
"Revision A1, A2.  Due to a silicon design error, SPI3 does not function.  Workaround: none."

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Sounds like ST ;D. Their process in general is hilarious: documentation is written before the product exist, describing their internal hopes of how it would function. When the device is finally actually designed (at HDL level, or even manufactured), the documentation is not updated to reflect the actual behavior. Instead, they make a mental diff, list of differences during design, and then roll dice on each difference. If five or six, they add the diff on a separate "errata" document. The thing is never fixed for any silicon revision so they don't consider them errors, "errata" for them just means "the actual documentation". If they throw 1-4, they just leave it out because the errata would be too long.

I'm quite positive they only hire sadists, because any normal human being would just modify the original documentation - much faster to do anyway!
PwrElectronics:
A  ::) for me was those International Rectifier power Fet datasheets.

TO-220 or D2PAK device, maybe others.  The front page says it can do 300A (!!!!!).

Fine print and a few calculations later...  One learns that that figure assumes somehow you keep the case at 25C and the die junction is at 175C max spec.  Elsewhere one learns that the pins on those packages are only rated for 75A anyway (also at 25C).
Psi:

--- Quote from: PwrElectronics on January 03, 2024, 11:12:25 pm ---A  ::) for me was those International Rectifier power Fet datasheets.

TO-220 or D2PAK device, maybe others.  The front page says it can do 300A (!!!!!).

Fine print and a few calculations later...  One learns that that figure assumes somehow you keep the case at 25C and the die junction is at 175C max spec.  Elsewhere one learns that the pins on those packages are only rated for 75A anyway (also at 25C).

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Did it say 300A continuous though? 
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