Fake OpAmps from eBay, how to test OpAmps

Testing suspicious LT1006CN8 and TLE2141CP operational amplifiers from eBay. How to test the output voltage swing (low and high state output voltage) and the common mode input voltage range. These are obviously fake and both behave exactly the same, despite having a different marking and coming from different sellers. The output voltage swing is quite poor on the negative side. The common mode input voltage range doesn't cover V- as it should (they're not actually ground sense op-amps). They don't meet their datasheet specifications.
UPDATE: I got refunded for both types.
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[@VladoT]

Be thankfull that they were actually opamps with the same pinout, I have come across fakes that are completly different part resulting in a complete circuit destruction on power-up.

[@jaro6985]

Yeah though then you know right away, vs spending hours troubleshooting.

[@Mr.Leeroy]

You can clearly see the texture of packages is intact, it is not a remarked part, but specially crafted counterfeit. And the fact that two random models got exactly the same die inside tells me that seller not just resells counterfeits, but orders specific die in requested blank packages and puts markings himself (or at least buys the whole batch from someone else knowing exactly what is the cost of insides).

[@noneofyerbeeswax8194]

Yes. This is not some "Xiao Fu Qing garage" level fake, this is big business.

[@DiodeGoneWild]

yes, no sharp corners around the top, no lines from the sanding direction. It seems that they got some cheap opamps with no markings on them.

[@Mr.Leeroy]

@@DiodeGoneWild All the remarked packages I got from Ali are more often laser etched off. They are not even trying. You may clearly see a rectangle smaller that the face of package, which is different in color too as light reflection is not the same with a different size of texture grain.

[@freakyjason477]

@@DiodeGoneWild They do have a process where they'll paint them with a tar like paint. Gives the same grainy surface finish which they then laser-etch. Using some paint thinner or acetone you can sometimes get it off and see the original markings underneath.

[@iamdarkyoshi]

I wonder if you can de-cap it and see any markings on the dies as to who made it

[@RicoElectrico]

Destructive decapping could be attempted with just a small blowtorch (obviously outside). Such small die should stay intact. I did this on some old motherboard chips and most survived.

[@BrianG61UK]

@@RicoElectrico Often just a paint stripper will be hot enough to soften the plastic.

[@WagTsX]

now you have to discover which OpAmp's are the original ones behind these

[@noneofyerbeeswax8194]

741's, what else?

[@liam3284]

What kind of opamp ignores the inverting input?

[@noneofyerbeeswax8194]

@@liam3284 Lots of them. They don't "ignore" it per se, they just reverse the phase. The 311 comparators have the same problem.

[@user-dx7ti9zg8t]

@@liam3284 tl061 in my opinion

[@thisisdvd8094]

It would be cool if there was a reverse datasheet search where you could enter the characteristics of a component and it would find matching datasheets.

[@sebastian19745]

I bought TL081 from my local store. 3 pieces, two of them identical and the third one different. I tsaid that those were the last parts they had. When I tested them, each was different, each with slightly different oscilation frequency (I did a relaxation oscillator to test them) and also as comparator, they behaved differently. Needless to say, they did not worked well in the preamp that I was building. Sadly, I could not return them because the policy of the store is that once you bought any active component, you can not return it. And they were quite expensives, 2.5€ each.

[@Alexelectricalengineering]

I buy my semiconductors only from reputable sources (Conrad, TME, etc.) Nice video as always 👍😎

[@Tom-90210]

100% of the time these days.

[@LMB222]

Conrad isn't reputable - they are a rip-off. Use Reichelt.

[@edgeeffect]

If your budget allows.

[@acoustic61]

@@edgeeffect Budget has nothing to do with using counterfeit parts.

[@1pcfred]

Counterfeiting is so bad that even trusted suppliers can end up with the junk. Dave Jones did a video where he ended up with bunk parts from a big supplier. It's less common than ebay but it still happens on occasion.

[@wimwiddershins]

eBay is a great source of eWaste. 😄

[@blueduck577]

it would be interesting to see the tests repeated with legit parts.

[@pvc988]

Do a decap. Heat and pliers should do the job.

[@tvelektron]

Maybe there is TL071 / TL081 / TL061 chip inside, the 2v "low" output and the phase reversal thing when with common mode voltage around 0V is typical for these opamps. There are a lot more parts acting like this one - most of them as old...

[@noneofyerbeeswax8194]

That would be easy to confirm because their common mode voltage includes the positive rail. Maybe Diode will see your comment and do the test? I suspect TL0XX are still too rich for the Xiao Fu Qing production though. Might be just the 741.

[@beatrute2677]

I got stung a couple of times on ebay/aliexpress for fake parts. Never again.

[@liam3284]

I would only buy from component suppliers I know are reputable. RS, Element 14, Mouser.

[@Chupacabras222]

We all were there, I guess ;)

[@Chupacabras222]

@@keith1200RetroComputers You are right. Currently I buy majority parts from LCSC. Occasionally from TME when I need something faster or something LCSC doesn't have. I haven't bought from Mouser or DigiKey for years (it was before they changed shipping price and conditions). Truth is that LCSC has much fewer parts than Mouser or DigiKey though.

[@LabArlyn]

Also fake ic's usually stick to a magnet.

[@mrnmrn1]

But a lot o real ones, too. Texas Intruments ICs usually have steel legs. Don't know why. I especially hate the vintage TI ones which have steel legs which are silver plated. They become unsolderable due to the black silver tarnish, you have to scrape the legs before you solder them, but if you scrape too hard and remove all the silver plating, they will rust...

[@godfreypoon5148]

@@mrnmrn1 Yep, and on really old gear quite often the steel rusts and subtly cracks the package open and the humidity gets in and ruins the IC.

[@alanvandusen76]

True there are a lot of dishonest sellers on many online platforms however there are some honest ones out there as well, it’s important to do a little research, seller rating, reviews, asking questions, requesting additional photos and even then some counterfeit parts may slip past. The good news is you can leave negative feedback so we all help each other avoid them all together and also block that seller from your profile so you don’t even see their trash listings again. Also good to point out that if the deal looks to good to be true it is probably not going to be a true original part. Good video and thank you for showing us the testing methods you found successful in identifying the frauds

[@pufferfish0101]

Yep just got stung the same way on AliExpress but gate drives, from the moment i saw them in my hands, flimsy pins, clearly sanded tops, the same markings on the back as yours, let the smoke out right away when tested, yea thats the last time im going to buy bulk cheap ics, thankfully i was able to get money back after sending them back

[@VVerVVurm]

I had some OpAmps from Amazon as a set and testing against the datasheet revealed not a single one was what it claimed. For some it was as simple as looking for the input protection diodes with a multimeter..

[@japanskakaratemuva5309]

How difficult would be to de-lid the die inside and do a reverse eng of it? It's an op-amp not a intel Pentium?

[@bumbochinelo4796]

Would be interesting to see what was the original chip. @Diode if you have time you could crack it open an put the chip under a magnifying len or microscope.

[@RicoElectrico]

I wonder if to achieve such low offsets LT/TI are using some serial bus with shift register to burn fuses post-packaging. Even packaging can introduce offset.

[@vikenemesh]

Calibrate the packaging offset into the precision resistor tuning until you get good parts. It works out when you can do 200 dies on a single wafer and incorporate feedback from testing processes later in the production line

[@MegaSunRise3]

EVEN MORE differential voltage... The output is still hiiiiiiiiiigh...

[@aivansama6265]

The floor is shaking...

[@noneofyerbeeswax8194]

The breaker still hasn't tripped...

[@andymouse]

May your salt flow freely my friend !

[@staryduren]

If you have few of each, put one of both types in fire for a while, resin will burn out an there will be possibility to compare chips under microscope ( metallization layers seems to survive such rough "decaping process", strong nitro acid works way better, but is hardly available now days) Regards from Poland.

[@ancientlink0]

Very good video👍

[@batman4e]

What are you doing with the fake ones? Do you dispose them off or use them for something useful?

[@noneofyerbeeswax8194]

He adds even more salt.

[@TriodeTetrode]

30 uV typical offset isn't unbelievable. Check MAX4238/MAX4239, 0.1 uV typical offset voltage ;)

[@andymouse]

Dave Jones used these in the 'micro current gold' so I used them in my version and they are great.

[@TriodeTetrode]

@@andymouse Yes I'm aware of that, that's where I also found them first ;) I also like a lot his potential replacement opa189 ;) I often need wider supply voltage that's where MAX4238/MAX4239 fails for me.

[@andymouse]

@@TriodeTetrode :)

[@abeleski]

Ewaste mostly contains genuine parts so I dont agree. Thats my usual source of parts.

[@edgeeffect]

And E. waste that you find dumped in other people's rubbish is even cheaper than E. Bay. ;)

[@DadofScience]

I wonder if this is why some of my circuits using opamps as a low side voltage comparator just don't work at

[@romancharak3675]

And thank you @DiodeGoneWild for the neat testing lessons.

[@jp040759]

VERY INTERESTING

[@KrotowX]

Counterfeit prouct market is ages old thing. Unfortunately it thrives on regular hobyists who don't want to buy chips for platinum price too. Send these fake opamps to someone who can open them without destroying internals. I'm sure both will be the same chips.

[@jendak7921]

It's not what they claim it is but otherwise you can be happy you got some unknown opamps not just blank package with wire going nowhere as they also sells.

[@n-steam]

Both equally useless.

[@jaakkolehto1487]

Here’s a tip completely unrelated to the video: If you want to open glued plastic enclosures fast, an upholstery stapler without the staples works great. You can open a power supply in a literal second with this method.

[@SilvaD702]

I miss the days when they'd sell you used parts as new, as opposed the totally fake crap these days

[@artbeautyandmadness3091]

At the end of the video I would take all the fake op-amps and wire the V+ and V- in parallel with each other and connect them directly to 230VAC. problem solved.

[@c.schandra2134]

Ca3140 can it be used because it's been used in welding machine???

[@DiodeGoneWild]

It could. Just the high state output voltage is a bit low. You have to use a very sensitive gate MOSFET (like PSMN2R0-30PL) or power this opamp using the voltage before the 7805.

[@fasted8468]

Hey do you know sferal hes saying you ought to talk to bob greenyer

[@daveamerion8177]

Look like both of them are old 741's, that have been remarked! 😆

[@user-tz3fd8hm4q]

That's why I always buy components from trusted suppliers. And I've never encountered any fake components there.

[@d.k.9406]

Danke! Thanks!

[@williefleete]

I wonder, if these are single op-amps they may be 741’s and possibly not even real ones, they all have similar pinouts etc

[@noneofyerbeeswax8194]

Yep!

[@barrymayson2492]

Been fighting fake chips for a long time after got scammed back in 2005. I try and use reclaimed parts as they are cheaper and are more likely to be genuine. Or failing that use large suppliers, more expensive but mostly genuine, and you have some recourse.

[@andymouse]

It's like getting Table when you paid for Kosher......cheers.

[@TheEmbeddedHobbyist]

Eek it's Mr mouse

[@2arc.]

I bought some AD01 10V REF on Aliexpress. Crap. Only gives 7V out. Thing to compare it is price. At mouse or lcsc price is 10x more freight but yeah, learned the lesson lol

[@whynot6795]

Very charmingly, the Chinese cross the branch on which they sit

[@ahmedbashar8571]

Remember to subscribe to his channel

[@godfreypoon5148]

They relabelled Microchip parts!

[@tiagoferreira086]

I heard if you connect them directly to the ac mains supply they work as intended 🤣

[@keithking1985]

Dodgy components... NEVER 😅😅😅😅 would love to see inside them. . 😊

[@yummyklown9226]

Dracula knows electronics?

[@romancharak3675]

I got burned once many years ago, buying ICs from ebay. Since then I will happily pay the higher price from the trusted Supply Houses. And I have never been disappointed.

[@claessjoblom9910]

The orginal have Steel pin very simple.

[@viperwizard491]

expensive version of 741

[@rc-fannl7364]

So much trash/fake electronics components going around these days.

[@fakduken9775]

Check their slew rate

[@KeritechElectronics]

Super dodgyyyyyyy!

[@godfreypoon5148]

Those DIP-8 packages look like feces.

[@LawpickingLocksmith]

Thanks for the hard work. It confirms what we now call ebay fakebay in Australia. Too many bad sheep doing the wrong thing.

[@MlokKarel]

Have you tried contacting the seller and confronting him with your measurements? 😀

[@WagTsX]

from my experience, they'll just tell you that you don't know what you are doing, and that the parts are fine, and other mumbo jumbo. It's like trying to evaporate a river using a hairdryer.

[@worroSfOretsevraH]

@@WagTsX That obviously won't work, because you don't have a long enough extension cord.

[@noneofyerbeeswax8194]

“Friend, chips fine. You doink it vronk. No mooney.”

[@inse001]

I successfully got my money back after complaining about counterfeit current mode OPAMPs. Had collected some evidence: manufacturer logo distorted, bandwidth not as stated in the datasheet. I also remember a “Rulycon“ capacitor that had failed in a PC power supply.

[@Thilina.channel]

👍👍👍👍

[@gfr2023]

the only thing I buy outside trusted electronics component vendors are crocodile clips pcb boards and things like that... I have wasted enought time on those fakes

[@DiodeGoneWild]

Boards are the number 1 thing that has to be a good quality. I don't want to put all the time and effort soldering components to a board that falls apart! Plus the components are lost in such case, if you don't want to put effort into desoldering and trippling the risk of heat damage... On the other hand, with a component in a socket, you can experiment ;)

[@Gooberslot]

I only use ebay for components that are old and and I can't get anywhere else.

[@poptartmcjelly7054]

Most likely a low-tier clone of the LM358 remarked as whatever else is pin-compatible

[@DiodeGoneWild]

LM358 is dual. But maybe something like 741...

[@tw11tube]

LM321 is the single op-amp chip that is similar to the LM358/LM324 chips. Nevertheless, the LM321/LM358/LM324 amplifiers are specifically designed to be used in single-supply applications, as input common mode range includes ground, also output voltage should go way below 1V. The chips in this video are *not* single-supply op-amps.

[@VEC7ORlt]

Opamps and ebay - sounds like a self inflicted injury...

[@fumthings]

you could even say... SUPER DODGY!!!

[@cjdelphi]

I have so many fake ics, but they all work lol

[@liam3284]

I suppose you can characterize them yourself and redesign?

[@cjdelphi]

@@liam3284 i simply work around the constraints i don't usually have a problem

[@menotyou8369]

"Don't always trust components from eBay" Don't EVER trust components from eBay. Although you can decrease the likelihood of buying counterfeits on eBay if you know what you're doing, you can never be 100% sure.

[@snipersquad100]

FakeBay you mean...

[@HPD1171]

wow you got scammed! so expensive and yet its fake. you paid even more then what a real one should cost.

[@gordonwedman3179]

Hopefully the Russians will buy these to use in their rockets. Money is probably getting tight there...

[@FaysalKhalashi]

😂😂😂

[@adaniel69]

no cat or fire extinguisher????????????????????????????????????????????????????????????????????????????????????????????????

[@tonywalton1464]

4:27. That's a cat.

[@adaniel69]

@@tonywalton1464 oops.... i guess the video was too boring and i missed that one...thanks!

[@tonywalton1464]

​@@adaniel69Always keep your eye out for the cat.

[@RaptorRotorHead]

You got burned hard dude

[@papanyanz]

Doddgyyy

[@1pcfred]

Super dodgy

[@AdamV20]

Now sandpaper the thermoplastic and show the dies

[@ChipGuy]

Never trust components from Ebay or Aliexpress.

[@pauldery7875]

Don't buy parts from Ebay, PERIOD!

[@captiveimage]

It's such a no brainer. If a chip from eBay is a fraction of the price of the same chip from a reputable retailer, its clearly a rip-off.

[@liam3284]

argh, fake parts!

[@UpLateGeek]

I hope you got a refund for those op amps! It really isn't worth buying op amps off Aliexpress or eBay.

[@DiodeGoneWild]

I'm trying to get a refund. It's not that much, but for the principle...

[@randomrandomizer]

Never buy components from eBay, specially if the seller is in China.

[@action4free369]

In german we can only buy at mouser, ebay,ali are alle fake. Transistor, diode, mosfet, all fake. Like the yx fakes 😂😂😂