This OPA161 with Extended 200mA Current Class A Output Single OP Amp Module comes from a Chinese seller on eBay.
Does anyone have experience with these op amps?
Does anyone have experience with these op amps?
From a non trusted source don't touch them.
It is an OPA1611. All you need to know about them. https://www.ti.com/product/OPA1611
Available through many trusted suppliers; Mouser, Farnell etc https://www.mouser.co.uk/ProductDetail/Texas-Instruments/OPA1611AID?qs=6805eV47HhZR18c7%2BQxbeA==&srsltid=AfmBOoqtb_LMwzaiJAUFJlreYVwstCQ5GZmhxrDQtfOk5S6encAzG1qt
They are over priced op amps but whatever floats your boat.
Buying from China .. it could be anything.
It is an OPA1611. All you need to know about them. https://www.ti.com/product/OPA1611
Available through many trusted suppliers; Mouser, Farnell etc https://www.mouser.co.uk/ProductDetail/Texas-Instruments/OPA1611AID?qs=6805eV47HhZR18c7%2BQxbeA==&srsltid=AfmBOoqtb_LMwzaiJAUFJlreYVwstCQ5GZmhxrDQtfOk5S6encAzG1qt
They are over priced op amps but whatever floats your boat.
Buying from China .. it could be anything.
€6.90 isn't overpriced, and the op-amp looks authentic. Yes, I know there are counterfeits everywhere, but counterfeiting a €3 op-amp and then adding a Class-A output stage to it would be stupid.
uA741 op amps are old school op amps for sale via Farnell for £0.22 each for genuine op amps. The same look a like op amp on ebay for £0.12 and they are fakes.
A fellow engineer bought a batch of them as they were cheap and sent me some as a sample to evaluate. They run hot, are very noisy and have a terrible slew rate.
Even 1N60p (SMD Germanium diodes) turned out to be standard Shottky diodes, not Ge at all! After replying to the supplier, the description changed; https://www.ebay.co.uk/itm/39656015...h6OKRQNyZ96GQDwfzr4VoZUw==|tkp:Bk9SR7yrzffTZQ
I will never trust fleabay as a supplier unless dealing with a trusted known, traceable supplier with a 100% track record.
A fellow engineer bought a batch of them as they were cheap and sent me some as a sample to evaluate. They run hot, are very noisy and have a terrible slew rate.
Even 1N60p (SMD Germanium diodes) turned out to be standard Shottky diodes, not Ge at all! After replying to the supplier, the description changed; https://www.ebay.co.uk/itm/39656015...h6OKRQNyZ96GQDwfzr4VoZUw==|tkp:Bk9SR7yrzffTZQ
I will never trust fleabay as a supplier unless dealing with a trusted known, traceable supplier with a 100% track record.
The first dead giveaway is that the TI logo is missing. These are pretty obvious fakes.
The soldering is amateurish at best. So why waste your money?
Tom
The soldering is amateurish at best. So why waste your money?
Tom
Not so. OPA1611 & OPA1612 don't have TI logos. I have plenty from Mouser & Digikey and none have logos.
That's odd. You're right, though. I just pulled one out. It doesn't have a TI logo either. That surprises me.
The one shown below came from TI. Pardon the crappy image quality. The production code format is different from the ones shown in the eBay picture, so unless you can find one with a similar format as in the eBay picture (two digits + three letters), I still wouldn't trust them. I also wouldn't buy because the assembly quality is pretty shoddy. They could at least have cleaned the flux off.
Tom
The one shown below came from TI. Pardon the crappy image quality. The production code format is different from the ones shown in the eBay picture, so unless you can find one with a similar format as in the eBay picture (two digits + three letters), I still wouldn't trust them. I also wouldn't buy because the assembly quality is pretty shoddy. They could at least have cleaned the flux off.
Tom
Why do people buy semiconductors off eBay when you can get the genuine articles from Mouser, RS or Reichelt?
Clearly the SMT components have been hand-soldered on those boards - big red flag there to start with, and there is too much solder on everything anyway. 200mA with so little heatsinking too? Nothing looks good about these.
I put the odds of genuine silicon below 5% these days, most/all the reputable sellers shut up shop on eBay a long time ago as they were undercut by all the fakers.
I put the odds of genuine silicon below 5% these days, most/all the reputable sellers shut up shop on eBay a long time ago as they were undercut by all the fakers.
I soldered them onto new sockets and inserted them into a TDA7293 composite feedback amplifier.
It used an original Mouser OPA1655. The sound is really good, better than with the OPA1655 or any other op amp. That's really a surprise!
https://www.facebook.com/share/p/19L8Y8is76/
It used an original Mouser OPA1655. The sound is really good, better than with the OPA1655 or any other op amp. That's really a surprise!
https://www.facebook.com/share/p/19L8Y8is76/
These two additional SOT-23 look like emitter-followers to boost output current.
Look at the pcb traces and you will confirm my assumption.
Without any biasing working in class-C.
A classic crossover distortion generator.
Real great design to fool the stupid long-noses.
But hey, if that sounds fabulous
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It may sound better (subjectively) than the OPA1611 itself. I've been adding a pair of BJTs (BD139/140, BD235/236) or single ended mosfet (IRF510) to the opamp output with a quiescent current of 30-100mA and it really sounds better. I'm currently using a Whammy headamp as a line preamp, and it's good, it sounds more powerful than just an opamp. I think Burson has something similar on offer, the V5i.
There's just no way that the quiescent current is set to 200mA on this Chinese one. That's 3W of dissipation per each output transistor at +/15V. This requires rather large coolers. With such a small cooling surface, even 30mA is questionable.
There's just no way that the quiescent current is set to 200mA on this Chinese one. That's 3W of dissipation per each output transistor at +/15V. This requires rather large coolers. With such a small cooling surface, even 30mA is questionable.
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I liked my cheap opamps from China, I have the original and the old stock counterfeit.
I replaced them with newer opamps, it give better specifications, but sound? to me it is all the same... I am testing this with my pcm58 China made, I am super happy! I have the genuine 1611 which are supposed to be the real deal on specifications...
They're only available in SMD here in Canada.
Mine are very different but close to the genuine image. (sorry but my version is better looking haha)
What will tell you is to remove them and look under them. They have a surprise!
The packaging from Digikey is impressive. There is a humidity indicator , came with 10% reading, and a desiccant into a sealed static proof and emi envelope, and they are inside a texas ins. original tube. Mine are the AID version.
I haven't had time to solder them to adapters yet.
I replaced them with newer opamps, it give better specifications, but sound? to me it is all the same... I am testing this with my pcm58 China made, I am super happy! I have the genuine 1611 which are supposed to be the real deal on specifications...
They're only available in SMD here in Canada.
Mine are very different but close to the genuine image. (sorry but my version is better looking haha)
What will tell you is to remove them and look under them. They have a surprise!
The packaging from Digikey is impressive. There is a humidity indicator , came with 10% reading, and a desiccant into a sealed static proof and emi envelope, and they are inside a texas ins. original tube. Mine are the AID version.
I haven't had time to solder them to adapters yet.
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There's no such thing as an "AID version". The device is marked OPA1611A, so it's possible that A denotes a revision number. That's somewhat unlikely but not impossible. D is the package option (SOIC). There's also a DRG package (SON) for the OPA1612. You can get them either in tubes with loose ICs inside (AID) or on reels with 2500 parts on tape (AIDR). It's the exact same chip just in different package options. It's all in the first page of the data sheet addendum:
Tom