[RetroTechie]

> 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 #.