Fake OpAmps from eBay, how to test OpAmps 

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.

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

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).

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

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

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.

eBay is a great source of eWaste. 😄

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

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

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

Also fake ic's usually stick to a magnet.

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...

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

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

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..

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.

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.

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

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.

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

And thank you @DiodeGoneWild for the neat testing lessons.

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.

Very good video👍

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

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?

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

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.

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.

VERY INTERESTING

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

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

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.

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

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.

Danke! Thanks!

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

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

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

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

Dracula knows electronics?

Remember to subscribe to his channel

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.

They relabelled Microchip parts!

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

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

The orginal have Steel pin very simple.

expensive version of 741

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

Those DIP-8 packages look like feces.

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

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

Check their slew rate

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

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

👍👍👍👍

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

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

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

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

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

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

Super dodgyyyyyyy!

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

FakeBay you mean...

Doddgyyy

"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.

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

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

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

Don't buy parts from Ebay, PERIOD!

You got burned hard dude

argh, fake parts!

Now sandpaper the thermoplastic and show the dies

Never trust components from Ebay or Aliexpress.

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

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

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