Re: Declining datasheet quality

On Tue, 30 Apr 2024 18:20:53 -0700, John Larkin
<jjSNIPlarkin@highNONOlandtechnology.com> wrote:
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On Tue, 30 Apr 2024 17:53:18 -0700, Don Y
<blockedofcourse@foo.invalid> wrote:
>

A colleague teaching a STEM course asked me for some details on WS2812's.
Digging through the datasheets I've been able to find seems like they
are sold only to hobbyists -- or, at least not to folks who have to
*design* with them!
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I can't seem to find any specification of Icc -- at MAX (255.255.255)
intensity and "dark" (0.0.0).
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Nor anything giving thermal characteristics of the package beyond
ambient (70C) and max junction temperature (80C) -- I suspect it
wouldn't be hard to melt the things if they dissipate any
appreciable amount of power!
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Is this the "typ" trend taken to its logical extreme (where we
don't really care how it MIGHT work in a given environment, beyond
"try it and see"?)

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Data sheets are increasingly awful. Some don't even say what the part
does. Some mechanical drawings have missing dims. And where is pin 1?
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People randomly distribute abs max, pin function tables, equivalent
schematics, electrical characteristics, whatever. Often there is no
date or version number. File names are bizarre, unrelated to the part
number.
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I especially hate a data sheet that covers a bunch of parts and
doesn't tell you what the difference is between them.
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Or covers a zillion parts and makes me build the part number, and then
guess whether it's an available thing.
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This isn't really bad:
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https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://cdn-shop.adafruit.com/datasheets/WS2812.pdf&ved=2ahUKEwi9sYqdpOuFAxV6IDQIHX-dCJ0QFnoECB0QAQ&usg=AOvVaw2wZFi_i6GR7eWbT12yqVZd

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Here's a good (ie, bad) data sheet example.
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https://www.rohm.com/datasheet?p=SH8JC5&dist=Digi-key&media=referral&source=digi-key.com&campaign=Digi-key
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It's not clear when they are talking about one die or two. The word
"and" is not helpful.
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It's not clear if this is one or two die, which can matter. I'll x-ray
one.