New face in op amp industry

[EERecordist]

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Thanks @IVX for the die photos.

There are many foundries, contract fabs, who can manufacture analog chips like these. Mask designs, the geometry of each layer of the chip, usually would be copyright, so hopefully the new company has sought a license from the original company.

It is a lot of work to go from the original company fab process to a different company fab process. And it is a lot of work to set up testing.

One of my early jobs was as the product engineer for chips and friends still currently work on all the details of foundries.

 

[Jimster480]

So they copied ricore?

 

[EERecordist]

So they copied ricore?

I do not know.

 

[IVX]

Finally, I found a hidden tiny mark identical on both chips, whatever RT or SG, and the marking is "SGMICRO". Conclusion: the "New face in op amp industry" doesn't actually exist but SG Micro.

 

[Veri]

Finally, I found a hidden tiny mark identical on both chips, whatever RT or SG, and the marking is "SGMICRO". Conclusion: the "New face in op amp industry" doesn't actually exist but SG Micro.
View attachment 378598


View attachment 378617

Solid detective work, IVX!

 

[Count Arthur]

like that:
View attachment 223720
that pic I've got from one discord member but I saw the same if not even worse at real headphones. These pare of clicks on the top of the wave is very clearly noticeable in any music.

Just me?

 

[Jimster480]

Honestly I am not surprised. Just straight purchasing designs from other companies has become the norm today.

 

[Njoy]

Finally, I found a hidden tiny mark identical on both chips, whatever RT or SG, and the marking is "SGMICRO". Conclusion: the "New face in op amp industry" doesn't actually exist but SG Micro.
View attachment 378598


View attachment 378617

Have they copied or based their design on already existing TI chip?

 

[IVX]

It looks like a student's project, I guess, not a copy of Ti or AD. So ugly clipping behavior isn't possible for AD, Ti, ST etc, as well as the fact that >7V voltage(at +/-15V rails) may kill the input. It is an amateur work as I feel.

 

[mc.god]

Well it's not a secret that sgm8262 is made by SGMicro
https://www.sg-micro.com/products/audio-op-amps

 

[IVX]

Well, OPA1612 is made by Ti so what? Who said it is a secret? The topic is about who are Richtek, Ricore, Semiteh, and other nonames "New faces in op amp industry".

 

[mc.god]

Well, OPA1612 is made by Ti so what? Who said it is a secret? The topic is about who are Richtek, Ricore, Semiteh, and other nonames "New faces in op amp industry".

I was reading during my commuting to office and kind of lost the focus on the thread topic

 

[Jimster480]

Well, OPA1612 is made by Ti so what? Who said it is a secret? The topic is about who are Richtek, Ricore, Semiteh, and other nonames "New faces in op amp industry".

IT seems that most of these are all clones of the same project which was likely made by a small team.
At the end of the day, if it works and it is halfway decent then it doesn't matter I guess..

 

[IVX]

It works but if you are smart enough, you should avoid using that as:
1) A headphone amp due to ugly clipping. Any circuits allowing clipping are not recommended but you'll find this opamp in 99% of chi-fi HP outputs.
2) As an input stage because >7v may burn this opamp input stage, as it said me "ricore" staff.
3) An unusually low phase margin doesn't let use that chip in a composite config.
Of course, the price is 1/3 of OPA1612 gives it some chance.

 

[Jimster480]

It works but if you are smart enough, you should avoid using that as:
1) A headphone amp due to ugly clipping. Any circuits allowing clipping are not recommended but you'll find this opamp in 99% of chi-fi HP outputs.
2) As an input stage because >7v may burn this opamp input stage, as it said me "ricore" staff.
3) An unusually low phase margin doesn't let use that chip in a composite config.
Of course, the price is 1/3 of OPA1612 gives it some chance.

But if the performance is good in the desired output amounts, then it's not really a problem.

 

[Jean-Paul Petrosyan]

I'm sorry to poke a dead thread, but does anyone know, by any chance, if SGM8262 are OK or best to be avoided as well? I was looking at the upcoming FiiO M21 DAP but after stumbling upon this thread I've become somewhat apprehensive... It's supposed to use "an op-amp combo of OPA1692 + SGM8262-2".

 

[IVX]

combo of OPA1692 + SGM8262-2

that combo looks like a mistake because OPA1692 has >8db, 2.625X times, higher voltage noise. What is the reason for putting a low noise opamp after the noisy one?

 

[solderdude]

What is the reason for putting a low noise opamp after the noisy one?

So that the 'audiophile noise/sound quality contribution' of the 'noisier op-amp' is faithfully amplified/buffered by the less noisy one ?

I'll let myself out ..

 

[Jean-Paul Petrosyan]

that combo looks like a mistake because OPA1692 has >8db, 2.625X times, higher voltage noise. What is the reason for putting a low noise opamp after the noisy one?

Ugh... The dark genius of Hi-Fi deeply imbued with the true spirit of audiophilia might be the reason, I guess.

Though maybe the wording choice was random and they're not implemented in this particular order. Would you say that it should be fine if that's the case, or are there's still grounds to be concerned about the SGM8262-2 possibly having the same clipping issues mentioned in this thread?

Thank you so very much for your answer!

 

[IVX]

Oh, it seems I mixed up SGM8262-2 vs SGM8261-2, I didn't try SGM8262-2.