Opamps under microscope

[bennetng]

Just found an interesting website showing a lot of hi-res die shots.
Not an audiophile website as it also shows many other kinds of chips as well.

https://zeptobars.com/en/?p=22
https://zeptobars.com/en/read/OPA627-AD744-real-vs-fake-china-ebay

 

[Vini darko]

First time I've actually seen the inside of an opamp. Thanks. I'm surprised at the amount of transistors in there.

 

[wynpalmer]

Just found an interesting website showing a lot of hi-res die shots.
Not an audiophile website as it also shows many other kinds of chips as well.

https://zeptobars.com/en/?p=22
https://zeptobars.com/en/read/OPA627-AD744-real-vs-fake-china-ebay
View attachment 71898

If you look at the ADI die, you will note the "SW". That I assume is Scott Wurcer's (the designer) initials. At one time ADI allowed us to put our initials (and sometimes other graffiti) on our designs. A real one also includes the manufacturer's symbol- e.g. ADI, the ADI triangle or BB in a "box", and the die name/revision.
Never buy any opamps from China. Never buy any "refurbished" opamps. Only buy from suppliers you trust, and if not then be diligent and test to confirm the specs- things like current consumption, offset, gain bandwidth product are relatively easy to measure and are generally sufficient to distinguish between real and fake devices. If you do find fakes then challenge the supplier and report them to Ebay. Ebay will do nothing about it, but at least you'll get your money back, and you can then safely write the vendor up in the feedback section as purveyors of fakes,

 

[bennetng]

That I assume is Scott Wurcer's (the designer) initials.

Interesting. Let's invite @scott wurcer to comment here.

 

[BostonJack]

Somewhere I have about a half boat of 4 inch wafers with various devices made by Analog Devices (they're in storage now, I think).
ADCs, DACs, analog multipliers, op amps, etc. They were pulled from scrap with the company's permission.

The cool thing about these is that the geometries are HUGE (similar to photo above). You can resolve all kinds of things and identify the multiplier core, input sections, etc. just by eye. The ADCs and DACs were usually laser trimmed, so you can see the trim tracks cut by laser as the device is tested. A simple optical microscope is all that's required.

I also have a single mask for a multi-core networking device (Cavium) which is an intricate pattern in a thick glass mount. An interesting object.
A little bit of clever illumination and this would make an object d'art.

The geometries there are more like 40 nanometer (if memory serves). Good luck imaging that!

Microelectronics is cool.

 

[scott wurcer]

Interesting. Let's invite @scott wurcer to comment here.

Yes I've seen the AD744 rebranded as an OPA627 before.

 

[Wes]

is that Tron in the left hand corner?

 

[scott wurcer]

BTW there are some wrong things on that site, for instance 2Ap is the marking on genuine BF862's they could have just looked it up. The other part could possibly simply be a second source from another manufacturer, fab, or a rebrand. You really have to verify by looking at specs.

 

[JohnYang1997]

"Never buy any opamps from China"
Hmmmm
Why do you have to do this?

 

[wynpalmer]

"Never buy any opamps from China"
Hmmmm
Why do you have to do this?

Simply put.
I have purchased "name brand" (i.e. TI/BB, ADI) opamps from China on a few occasions, and I have assessed samples that others have sent to me, and in each and every case they have been fake, including supposed "refurbished" ones.
I'm certain that there are valid resellers out there, it's just that I've not encountered any and the risk seems high- particularly if you are not willing/able to assess the validity of the device. Hence the recommendation.

 

[JohnYang1997]

Simply put.
I have purchased "name brand" (i.e. TI/BB, ADI) opamps from China on a few occasions, and I have assessed samples that others have sent to me, and in each and every case they have been fake, including supposed "refurbished" ones.
I'm certain that there are valid resellers out there, it's just that I've not encountered any and the risk seems high- particularly if you are not willing/able to assess the validity of the device. Hence the recommendation.

It would be fine if you said: Don't buy opamps from dodgy ebay sellers in China. There are reputable sources in China. If not, you can imagine the situation that all Chinese companies have to buy from Mouser/Digikeys and wait over a week.
And I know the original comment is for people outside China. Just a 'bruh' moment for me.

 

[wynpalmer]

It would be fine if you said: Don't buy opamps from dodgy ebay sellers in China. There are reputable sources in China. If not, you can imagine the situation that all Chinese companies have to buy from Mouser/Digikeys and wait over a week.
And I know the original comment is for people outside China. Just a 'bruh' moment for me.

A "bruh" moment? Really? Presumably you expect an apology from me for vexing you?
And how does one know that they're "dodgy Ebay sellers" and not "non-dodgy Ebay sellers"?
And, yes, this comment was obviously intended for non Chinese purchasers- which merits a "duh" moment from me. I would expect purchasers within China have reliable means of obtaining devices and presumably also have means for redress if they they are "conned".
However, if US and European residents (yes, purchasers have sent me opamps from Europe for evaluation of their validity) buy such goods then it's definitely a case of caveat emptor.
Yes, I do prefer to use Latin rather than street slang...

 

[JohnYang1997]

A "bruh" moment? Really? Presumably you expect an apology from me for vexing you?
And how does one know that they're "dodgy Ebay sellers" and not "non-dodgy Ebay sellers"?
And, yes, this comment was obviously intended for non Chinese purchasers- which merits a "duh" moment from me. I would expect purchasers within China have reliable means of obtaining devices and presumably also have means for redress if they they are "conned".
However, if a US and European residents (yes, purchasers have sent me opamps from Europe for evaluation of their validity) buy such goods then it's definitely a case of caveat emptor.
Yes, I do prefer to use Latin rather than street slang...

I wasn't very serious on this. Now, there you go.
https://lcsc.com/en
Say no more.

 

[BostonJack]

I wasn't very serious on this. Now, there you go.
https://lcsc.com/en
Say no more.

I have a somewhat off topic observation about buying things from China: [I have had only good experiences just using common sense on who is likely to be a reliable seller]. I want to buy an altitude simulation device, which is essentially an appliance that produces a stream of air with reduced O2 content that is settable to specific altitude-equivalents (i.e. 8,000 feet, 12,000 feet, etc.) with a tent supplied, such that the subject can sleep at simulated altitude. This is to stimulate my body to acclimate to altitude, mainly by producing more red blood cells.

Cost from China: $700. Cost from U.S. vendor: $3500.

So this is a piece of equipment that could kill or damage me if it hard-failed. It has detectors and fail-safe mechanisms. I would add a
tertiary fail-safe using a pulse-ox detector and an alarm and separate ventilator for the tent.

Many 100's of millions of people fly/train/ride in elevators, trust medical equipment etc., etc. every day on Chinese designed and built equipment.
I believe that it is a mistake to not examine these cases on best available evidence rather than broad generalizations.

My company's safety director suggested that I date a nurse to reduce the chances of a night time O2 mishap. An ER nurse might be into it.

 

[scott wurcer]

Simply put.
I have purchased "name brand" (i.e. TI/BB, ADI) opamps from China on a few occasions, and I have assessed samples that others have sent to me, and in each and every case they have been fake, including supposed "refurbished" ones.

There are several levels of "fake", have you come across any op-amps or old multi-bit DAC's where a Chinese manufacturer has used bootleg masks and actually fabricated fake parts? I have not, virtually everything I have seen has been rebranded wrong or lower grade parts sometimes even power FET's where the pins are not even in the same order.

 

[wynpalmer]

I wasn't very serious on this. Now, there you go.
https://lcsc.com/en
Say no more.

There are several levels of "fake", have you come across any op-amps or old multi-bit DAC's where a Chinese manufacturer has used bootleg masks and actually fabricated fake parts? I have not, virtually everything I have seen has been rebranded wrong or lower grade parts sometimes even power FET's where the pins are not even in the same order.

No Scott, I have only seen rebranded parts. In all cases the parts were significantly different in specification from the devices they purported to be.

 

[RayDunzl]

I don't see any little triangles in it.

Maybe it is a fake.

 

[RayDunzl]

There are reputable sources in China.

Maybe, but you might admit there's a lot of bad reputation to overcome.

Little Woman bought a can of Wild Alaskan Salmon from the Dollar Store yesterday (she likes to do dumb stuff like that).

Guess where it was canned?

I won't eat it.

 

[RayDunzl]

Just a 'bruh' moment for me.

I wouldn't worry, you have plenty of market penetration as it is.

I went to the new IKEA soon after it opened here in Tampa.

Figured I'd check out the Swedish quality and all that stuff, maybe things from other parts of Europe.

Nope.

 

[JohnYang1997]

Maybe, but you might admit there's a lot of bad reputation to overcome.

Little Woman bought a can of Wild Alaskan Salmon from the Dollar Store yesterday (she likes to do dumb stuff like that).

Guess where it was canned?

I won't eat it.

https://lcsc.com/en
Not good enough still?

If there's one known reputable source, you can consistently get good stuff, no?