The EEVBlog[1] video about this has a nice example of only a single chinese manufacturer offering the same stuff as TI now does, even with the same PNP instead of NPN topology. All the others are comparable to the original.

1: https://youtu.be/22ZmmZ67SMY

> Different vendors' 5532s are supposed to be able to be treated as the same SKU — literally dumped into co-mingled stock in warehouses — with no ill consequence!

That may be true for a small webshop or a brick-and-mortar electronics store (what few of those still exist). Or be true for end users / manufacturers of equipment that includes such a part.

But (afaik) that's not how it works for large reputable distributors like Mouser, Digikey & co. You don't order a generic "5532" there, you order a 5532 from <specified manucturer> there. Part from manufacturer A may, or may not be interchangeable with same-numbered part from manufacturer B. There's even some parts that have same # but very different function between manufacturers. In other words: buyers, designers do your homework.

Likewise in a design, if you specify "5532" that should read as "any manufacturer's 5532 should do". If not (or unsure / untested), one should specify the part including its manufacturer. Or a list of acceptable manufacturer/part# combo's.

Ofcourse changing the spec significantly for a jellybean part like discussed here (and one with many 2nd sources), that's just evil. Change a part like that, give it its own part #.

Dave Jones also did some videos on the LMV321 used in his uCurrent Gold project. The AS5X variant caused issues while others worked fine.

Looking now, a document source suggests the AS5X variant in the parts list... but it's explained in the video around 19:30

https://www.youtube.com/watch?v=1VlKoR0ldIE

>You're supposed to be able to order "a" 5532 without specifying the supplier

This is not true.

>because many vendors produce "a" 5532

This is true, in the sense of a "5532-type part". But you will note that all the 5532 variants have different manufacturer's part numbers (prefixes and suffixes) to prevent this confusion. They don't just do that for branding.

>and they're all the same.

This is emphatically and trivially not true, and it tells me you haven't done the work of carefully comparing data sheet specs across suppliers. Try it, you'll learn something.

>Different vendors' 5532s are supposed to be able to be treated as the same SKU — literally dumped into co-mingled stock in warehouses — with no ill consequence!

That might happen somewhere, but authorized distributors do not do this and volume manufacturers do not do this. You might have an internal part number with an authorized suppliers list that includes more than one variant of 5532 that has been vetted for production.

>And yes, until TI's recent move, that was true of the 5532. All the other vendors' 5532s had matching datasheet specs

Again, emphatically and trivially not true. Take a careful look at the NJM and On Semi data sheets. Spec by spec. Do the work and be amazed.

>the warehouse they're sourcing from has comingled any TI 5532s into the general 5532 stock

Authorized distributors do not do this. It gets hairy when you're sourcing NOS from grey market dealers for old designs or in severe part crunches like 2020-2022 era, but that's a different story.

>no real recourse except to change your entirely supply chain to one that specifically excludes TI

This concept is backwards. You would have an internal part number for 5532-type op amp, and it would have an authorized vendors list that would only include vetted parts. "Any 5532 but TI" is asking for trouble from someone else.

And parts do change or get updated and if you are buying from authorized distributors for production you and your supply chain and quality people will get product change notices. At that point it's your job (or the component engineer's, if you're fortunate enough to have one) to validate the new version or find a suitable alternate.

It has worked this way since the days of the vacuum tube, so there probably is some legal precedence somewhere. I think part of this with the NE5532 is just that these days most EEs spend most of their time with digital where the data sheet and its spec is absolute; in the linear world the spec sheet is an ideal and an average because the parts themselves are an ideal and the real world never lines up with the math. Back when the NE5532 came out it was still common to see power supplies that were unregulated or barely regulated or cheap regulators with poor tolerance that would vary a fair amount with wall voltage and massive tolerances on passives, data sheets and EEs took this into account, most parts would survive max voltage but there would be a higher failure rate, so run at 70% or 80% and you don't have to worry about it.

In these days of cheap SMPS and EEs that are trained with a strong lean towards digital and much improved IC fab, the max seems to be treated as the max safe voltage for good reliability and life, and you don't have to worry much about the tolerances of everything else so much. Back in the 90s when I was learning this stuff, the old EEs scolded me when ever I ran at max voltage and would patiently explain it all to me and that even if it can operate at that voltage, you can't be certain your PS will still be putting out that voltage in a year, parts drift as they age and accidents happen and the world is not ideal. They were right.

They’re just not really standardized at all, especially semiconductors. Not in the sense you’d expect naively. Some were a long time ago, and supposedly the old Japanese sc parts were, down to die geometry and process. But otherwise, the part number means “this is like the part with a similar number first made by someone else”, not “this is an exact replacement in every way”