Was I sent fake op amps?
Jul 21, 2010 at 9:15 PM Thread Starter Post #1 of 8

stew1234

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I purchased some OPA627AP op-amps from a seller in China on ebay and received these. They don't have the trademark sign next to the BB logo or the notch in the side every OPA627 I could find online does. Could these be fake? They weren't particularly cheap so I have no reason to think they're fake other than I can't find any online that look like the ones I received. I wont have an amp to plug them into for a while (I have to finish building it) so I don't really have a way of testing for the time being.   
 
And looking here http://focus.ti.com/general/docs/product/topsidemarking.tsp?part=OPA627AP&pkg=P&pin=8&actionPerformed=viewTopsideMarking#33
 
I do not see any from TI that match their markings...
 

 
Jul 21, 2010 at 11:00 PM Post #3 of 8

rawrster

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Unless you have a way of testing it the best you can do is hope they are real. There definitely are fake opamps especially the more popular ones such as an opa627. High price also does not automatically mean it is real.
 
Jul 21, 2010 at 11:59 PM Post #4 of 8

stew1234

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There's a 7 day full refund policy so there isn't too much of a risk - the only answer is I haven't been burned yet on ebay... that being said I know it's not the most secure. I've asked TI about then and will wait and see. 
 
Jul 22, 2010 at 3:36 AM Post #5 of 8

krmathis

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They sure can be, as they make pirate copies of almost anything in China.
 
Jul 22, 2010 at 11:09 AM Post #6 of 8

vixr

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So, the op amps would most likely be a lesser quality device with similar performance specs with the 627 silkscreen on them? How messed up is that? All the OPA627s I bought have white lettering on them (from Mouser)
 
Jul 22, 2010 at 2:14 PM Post #7 of 8

Yoga Flame

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This might help. But it's from 2008, so I wouldn't be surprised if counterfeiters have adapted by now.
 
From: http://www.head-fi.org/forum/thread/316937/fake-opa627-s-in-the-wild/60#post_4243931
Quote:
Just take out your opa627 from the socket and measure the resistance between pin 1 and pin 5 using a multimeter. Try red on pin 1 and black on pin 5, then black on pin 1 and red on pin 5, both measure should read 45-55K. 
 

 
Jul 27, 2010 at 4:32 PM Post #8 of 8

Mad Max

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If you want to buy opamps from eBay, you probably want to stick with US sellers with plenty of feedback, but in that case you may as well just order from Digikey and save a little or order smaples from BB, ADI, LT, and Intersil if you can.
 

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