Path: ...!Xl.tags.giganews.com!local-1.nntp.ord.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail NNTP-Posting-Date: Thu, 02 May 2024 22:56:02 +0000 From: john larkin Newsgroups: sci.electronics.design Subject: Re: Declining datasheet quality Date: Thu, 02 May 2024 15:56:02 -0700 Message-ID: References: <6j533j1rloi61f1ean3c49ar8rbp8u69up@4ax.com> User-Agent: ForteAgent/8.00.32.1272 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 55 X-Trace: sv3-XQGlJ+7Q4ebvcwE8MslTG/VtQ8XMjB/MpA1BgtqL494qgV4D8tJtG1g8817s8u26LcOstS5dkDb2V0r!hP4IZ9Q/khIs5dUTFNqjbSM38ByAxDxCVt8vFN1DTaXri2DaIoDvpCEM40Bg4EmyPqNbHGmXQkMT!nn3kKQ== X-Complaints-To: www.supernews.com/docs/abuse.html X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 3451 On Thu, 02 May 2024 11:59:38 -0700, john larkin wrote: >On Tue, 30 Apr 2024 18:20:53 -0700, John Larkin > wrote: > >>On Tue, 30 Apr 2024 17:53:18 -0700, Don Y >> 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! >>> >>>I can't seem to find any specification of Icc -- at MAX (255.255.255) >>>intensity and "dark" (0.0.0). >>> >>>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! >>> >>>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"?) >> >>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? >> >>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. >> >>I especially hate a data sheet that covers a bunch of parts and >>doesn't tell you what the difference is between them. >> >>Or covers a zillion parts and makes me build the part number, and then >>guess whether it's an available thing. >> >>This isn't really bad: >> >>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 > >Here's a good (ie, bad) data sheet example. > >https://www.rohm.com/datasheet?p=SH8JC5&dist=Digi-key&media=referral&source=digi-key.com&campaign=Digi-key > >It's not clear when they are talking about one die or two. The word >"and" is not helpful. > >It's not clear if this is one or two die, which can matter. I'll x-ray >one. https://www.dropbox.com/scl/fi/eahb9v65w2d13isrbsw5a/208-1006.jpg?rlkey=ist02aewzmdz9rjly97ie4ry4&raw=1