Genuine Or Fake Burr Brown OPAMP???

[bluebunny]

If true, then my 2134 shown above is fake. I got it from Tayda - do we know whether or not Tayda sells fakes?

I've bought 2134s from Tayda in the past.  While I couldn't say for sure whether they were genuine or not, they were certainly functional, and not noisy or anything like that.

[mickeybellinello]

Try measuring the offset voltage.

https://www.vintage-radio.net/forum/showthread.php?t=93127

Interesting, I'll take a look!

No notch between pin 1 and 8 and shallow pin 1 indent = Fake:

https://www.stereo.net.au/forums/topic/289098-fake-opa2134s/

I tought the same when I received it

[GGBB]

I've bought 2134s from Tayda in the past.  While I couldn't say for sure whether they were genuine or not, they were certainly functional, and not noisy or anything like that.

That's been my experience with the ones I bought as well. I have a-b compared them with TL072 in a couple of circuits and didn't notice any difference, but I'm not sure I should since TL072 is quite decent as well.

[iainpunk]

what is so special in the Burr Brown opamps?

are they so much better? i never heared the diference between an LM308 and a Ua741, why is it such a big deal?
most schematics seem to work with every opamp and good circuit design is more important than mojo parts anyways.

[EBK]

what is so special in the Burr Brown opamps?

are they so much better? i never heared the diference between an LM308 and a Ua741, why is it such a big deal?
most schematics seem to work with every opamp and good circuit design is more important than mojo parts anyways.

I'll provide a somewhat unsatisfying answer. 

Sometimes we pick an op amp with better performance characteristics precisely because we want it to impart less mojo. Depending on the application, we could be after lower noise, higher current capability, better slew rate for high gain circuits, better offset voltage. 

[ElectricDruid]

At the end of the day people are still buying stuff off of ebay because it's cheap.
<snip>
So it's really boils down to buying from known and trusted suppliers.

I think this hits the nail on the head. If Analog Devices won't sell you the chip on their own site for less than $5, how is some dude on eBay offering it for $2.50? Be afraid, be very afraid!
The 'known and trusted' suppliers all have prices that make sense when compared to manufacturer's own prices. Anyone who doesn't isn't to be trusted.

Of course, for stuff that's out of production, this gets more complicated. At that point, rarity starts to be a big issue and guaranteeing that something is what it claims to be is more difficult. If someone offered me (for example) 50 x SSM2040 chips for a decent price, how would I know they were not fakes? There's no way beyond getting a few and testing them, and then checking that any subsequent chips are the same as those ones.

[GGBB]

If Analog Devices won't sell you the chip on their own site for less than $5, how is some dude on eBay offering it for $2.50? Be afraid, be very afraid!

Great point. TI will sell you the OPA2134 PDIP for $2.05 if you buy 1000 (http://www.ti.com/product/OPA2134/samplebuy). I paid $2.45 for mine from Tayda (6 years ago - I keep old email), and I think they would probably buy in bulk so maybe mine are okay. Do you remember what you paid mickeybellinello?