4 ms·

This sort of thing really annoys me. Part numbers are for use of engineers, not for the marketing dept. If you change the specs, change the part number.

by RachelF 4mo ago

buescher 4mo ago
It annoys me too but part numbers are not a spec but more of a strong hint. The attitude of the industry is that it’s up to you to read data sheets carefully and test. Even for a 2N2222 or whatever.
- Our_Benefactors 4mo ago
  > The attitude of the industry is that it’s up to you to read data sheets carefully and test. Is this backed up by court precedent? This seems like you could easily claim damages due to a differently speccd part. I’m not doubting that’s how the industry operates, but it seems wrong so I’m curious what is supporting such a dysfunctional form of doing business.
  - buescher 4mo ago
    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”
  - ofalkaed 4mo ago
    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.
- cryo32 4mo ago
  MPF102 is my favourite there. “It’s a JFET” is your only guarantee. Buy binned parts and design spec spread into it.
- derefr 4mo ago
  Keeping in mind, though, that this is a jellybean part. You're supposed to be able to order "a" 5532 without specifying the supplier, because many vendors produce "a" 5532, and they're all the same. 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! (And yes, until TI's recent move, that was true of the 5532. All the other vendors' 5532s had matching datasheet specs, including the 22V max input voltage. Because a design that was built for "a" 5532 was usually built to run it up to 100%; and that a vendor couldn't offer their part as a swap-in if it couldn't do that.) But now, if your purchasing department (or the supplier they purchase from) happens to order TI 5532s — or if the warehouse they're sourcing from has comingled any TI 5532s into the general 5532 stock — then your product is now broken, with no real recourse except to change your entirely supply chain to one that specifically excludes TI.
  - consp 4mo ago
    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 https://youtu.be/22ZmmZ67SMY
    - rbanffy 4mo ago
      Would be nice to call it a 5532a or something like that.
  - Throwthrowbob 4mo ago
    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 https://www.youtube.com/watch?v=1VlKoR0ldIE
  - RetroTechie 4mo ago
    > 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 #.
- CamperBob2 4mo ago
  Specs are just that... specs. A 7400 is one thing, but if you designed a circuit that barely avoids oscillating with a 10 MHz GBW, an unsolicited "upgrade" to the opamp that raises its GBW to 12 MHz may be more of a disaster than a favor. Frankly it's not OK to "upgrade" plain old TTL parts, either, since a faster 7400 might expose a race condition that never caused problems before, or cause EMI problems that didn't exist before.
rpaddock 4mo ago
I can see both sides of this. I really want different part numbers for the same reason you do. However we deal with a lot of regulated products and to just open a case at one of the Government Paper-Pusher Regulators will cost us $5,000 to just change the part number. We are a small company and $5k hurts.
- vanderZwan 4mo ago
  I'm sure it does and you have my sympathies, but your situation would not be a reason to let Texas freakin' Instruments off the hook. They're not exactly "a small company", and I wouldn't be surprised if the $5k would have been cheaper than dealing with the response to this, so this just comes across as incompetence on their end.
- deleted 4mo ago
  [deleted]
- rsynnott 4mo ago
  ... How do the "paper-pusher regulators" feel about getting a completely different part unannounced? I would guess unhappy, tbh. Like based on the thread it's not trivial changes.
  - Jalad 4mo ago
    Kind of like keeping a certain plane model number the same, and claiming that re-training isn't needed even when it clearly is
    - snypher 4mo ago
      An iPhone 17 is very different to an iPhone 3G, but we can pretend to ignore the fact one had its first flight in 1968 and the other in 2016.
rbanffy 4mo ago
Kind of. I want all 7400s to be four NAND gates, regardless of how they are implemented. As long as the results are correct, you might as well put a little ARM controller pretending to be four NAND gates. For analog parts, I agree any change to the data sheet should receive at least a different suffix letter.
- OptionOfT 4mo ago
  I disagree. At a certain moment you start to rely on behavior, knowingly or unknowingly. These kind of changes might surface bugs that you never had. https://xkcd.com/1172/ https://xkcd.com/1172/
  - rowanG077 4mo ago
    If you relied on behavior not in the spec this is on you.
    - adrian_b 4mo ago
      In these cases of the TI parts, some of their most important specifications, like maximum supply voltage, noise and slew rate, have been changed, and not by a few percent, but by even a factor close to 2. For so great changes, it is really not acceptable to use the same part number, especially when the part numbers have been in widespread use for many decades, so most users who are familiar to them will not bother to check again their latest specifications, where they could notice that they are no longer what they knew.
  - rbanffy 4mo ago
    I don’t care for bugs that never manifest themselves under intended uses.
  - sidpatil 4mo ago
    In software, this is known as Hyrum's Law: https://www.hyrumslaw.com/ https://www.hyrumslaw.com/
hulitu 4mo ago
> If you change the specs, change the part number. They took it from SW. You know this joke with "Windows is a single platform" ? Or the joke with "use rust if you can compile it" ? Or "your browser version is not supported" ? Enshitification reaches everything.

This sort of thing really annoys me. Part numbers are for use of engineers, not for the marketing dept. If you change the specs, change the part number.

by RachelF 4mo ago

This sort of thing really annoys me. Part numbers are for use of engineers, not for the marketing dept. If you change the specs, change the part number.

buescher 4mo ago

It annoys me too but part numbers are not a spec but more of a strong hint. The attitude of the industry is that it’s up to you to read data sheets carefully and test. Even for a 2N2222 or whatever.

Our_Benefactors 4mo ago
> The attitude of the industry is that it’s up to you to read data sheets carefully and test. Is this backed up by court precedent? This seems like you could easily claim damages due to a differently speccd part. I’m not doubting that’s how the industry operates, but it seems wrong so I’m curious what is supporting such a dysfunctional form of doing business.
- buescher 4mo ago
  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”
- ofalkaed 4mo ago
  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.
cryo32 4mo ago
MPF102 is my favourite there. “It’s a JFET” is your only guarantee. Buy binned parts and design spec spread into it.
derefr 4mo ago
Keeping in mind, though, that this is a jellybean part. You're supposed to be able to order "a" 5532 without specifying the supplier, because many vendors produce "a" 5532, and they're all the same. 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! (And yes, until TI's recent move, that was true of the 5532. All the other vendors' 5532s had matching datasheet specs, including the 22V max input voltage. Because a design that was built for "a" 5532 was usually built to run it up to 100%; and that a vendor couldn't offer their part as a swap-in if it couldn't do that.) But now, if your purchasing department (or the supplier they purchase from) happens to order TI 5532s — or if the warehouse they're sourcing from has comingled any TI 5532s into the general 5532 stock — then your product is now broken, with no real recourse except to change your entirely supply chain to one that specifically excludes TI.
- consp 4mo ago
  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 https://youtu.be/22ZmmZ67SMY
  - rbanffy 4mo ago
    Would be nice to call it a 5532a or something like that.
- Throwthrowbob 4mo ago
  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 https://www.youtube.com/watch?v=1VlKoR0ldIE
- RetroTechie 4mo ago
  > 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 #.
CamperBob2 4mo ago
Specs are just that... specs. A 7400 is one thing, but if you designed a circuit that barely avoids oscillating with a 10 MHz GBW, an unsolicited "upgrade" to the opamp that raises its GBW to 12 MHz may be more of a disaster than a favor. Frankly it's not OK to "upgrade" plain old TTL parts, either, since a faster 7400 might expose a race condition that never caused problems before, or cause EMI problems that didn't exist before.

rpaddock 4mo ago

I can see both sides of this. I really want different part numbers for the same reason you do. However we deal with a lot of regulated products and to just open a case at one of the Government Paper-Pusher Regulators will cost us $5,000 to just change the part number. We are a small company and $5k hurts.

vanderZwan 4mo ago
I'm sure it does and you have my sympathies, but your situation would not be a reason to let Texas freakin' Instruments off the hook. They're not exactly "a small company", and I wouldn't be surprised if the $5k would have been cheaper than dealing with the response to this, so this just comes across as incompetence on their end.
deleted 4mo ago
[deleted]
rsynnott 4mo ago
... How do the "paper-pusher regulators" feel about getting a completely different part unannounced? I would guess unhappy, tbh. Like based on the thread it's not trivial changes.
- Jalad 4mo ago
  Kind of like keeping a certain plane model number the same, and claiming that re-training isn't needed even when it clearly is
  - snypher 4mo ago
    An iPhone 17 is very different to an iPhone 3G, but we can pretend to ignore the fact one had its first flight in 1968 and the other in 2016.

rbanffy 4mo ago

Kind of. I want all 7400s to be four NAND gates, regardless of how they are implemented. As long as the results are correct, you might as well put a little ARM controller pretending to be four NAND gates. For analog parts, I agree any change to the data sheet should receive at least a different suffix letter.

OptionOfT 4mo ago
I disagree. At a certain moment you start to rely on behavior, knowingly or unknowingly. These kind of changes might surface bugs that you never had. https://xkcd.com/1172/ https://xkcd.com/1172/
- rowanG077 4mo ago
  If you relied on behavior not in the spec this is on you.
  - adrian_b 4mo ago
    In these cases of the TI parts, some of their most important specifications, like maximum supply voltage, noise and slew rate, have been changed, and not by a few percent, but by even a factor close to 2. For so great changes, it is really not acceptable to use the same part number, especially when the part numbers have been in widespread use for many decades, so most users who are familiar to them will not bother to check again their latest specifications, where they could notice that they are no longer what they knew.
- rbanffy 4mo ago
  I don’t care for bugs that never manifest themselves under intended uses.
- sidpatil 4mo ago
  In software, this is known as Hyrum's Law: https://www.hyrumslaw.com/ https://www.hyrumslaw.com/

hulitu 4mo ago

> If you change the specs, change the part number. They took it from SW. You know this joke with "Windows is a single platform" ? Or the joke with "use rust if you can compile it" ? Or "your browser version is not supported" ? Enshitification reaches everything.