RME ADI-8 DS MKIII opamp

[andow]

A few days ago I noticed that the first channel of the AD converter stopped working on my ADI-8. I narrowed the problem down to a 4580 opamp which has input signal present, but no output. I guess swapping this chip will fix the problem!
The problem is, I can't find this exact chip (see attachment) - does somebody know where I can get these? And could I also use another 4580 without this channel differing from the others?
I'm not really experienced with SMD stuff... (I will get the chip and let a colleague do the soldering.)

 

[scott2000]

Mouser has some

https://www.mouser.com/Semiconductors/Audio-ICs/Audio-Amplifiers/NJM4580-Series/_/N-4gxtf?P=1yw782n

Can't imagine there would be any differences.....

 

[Bo Deadly]

That looks like a TSSOP-8 so I don't think you're going to find a good alternative. I wouldn't use anything else anyway. The 4580 is a good OA. Mouser and Digikey have them.

The real problem is that it could be tricky to get that off without damaging the underlying traces. I would either put a ton of extra leaded solder on and move the iron tip back and forth while trying to lift that side with tweezers. Worst case scenario would be to very carefully cut the leads with a utility knife.

 

[andow]

Thanks for your help!

I guess I wasn't clear, of course I found a 4580 at Mouser. I just don't know if these are the EXACT chips that are used in the RME, and I really would like to replace it with the same one.
Can you tell me what E161F means?

@squarewave: Actually I won't replace it myself, as I have limited experience with SMD stuff. And this really looks tricky! I'll find someone who can replace the chip for me.
RME wants 250€ as a lump sum for repairs, which is a lot if it's really just one opamp...

 

[scott2000]

Can you tell me what E161F means?

It's most likely a manufacturing code.... Like lot/batch date, etc..... I'm not sure what's what in regards to this particular chip....


I've had good luck with narrow solder wick and flux on removing these types???  The wicks that have flux are pretty good....

I'm guessing you've also checked that the op amp is getting power???

 

[Bo Deadly]

RME wants 250€ as a lump sum for repairs, which is a lot if it's really just one opamp...

I don't know if I agree. Does that include shipping? I don't know what your time is worth but replacing that one part could take hours. And if the board is damaged RME will presumably replace it if they do the work. They definitely won't if you do it. And they will presumably test it to verify that it's actually working correctly. Do you have an audio analyzer?

Personally, I would probably do it myself but only because I'm impatient and a little reckless.

 

[volker]

Hours?  With the pcb in front of me, that's a five minutes job, and that includes a coffee break.


This is the correct part.

And like squarewave said, you can't be sure this is the only fault. Opamps usually don't just stop working randomly.

 

[Bo Deadly]

Hours? 

Between asking about it on some forum and then looking up the part and ordering it and then getting everything setup and then testing it and testing it again and then something isn't right and you have to think about it for a while only to realize it's not a problem and then blah, blah, blah, ... Yes, the actual desoldering, cleaning and soldering it back doesn't take long (although realistically it's more like 30 minutes not 5). But all together it adds up.

 

[andow]

I'm guessing you've also checked that the op amp is getting power???

Yes, voltages are +/- 16V.

This is the correct part.

And like squarewave said, you can't be sure this is the only fault. Opamps usually don't just stop working randomly.

Thanks!
Yeah, to be honest I still don't know if I should replace the chip myself or just send the converter to RME.... :-\
I never had a problem with the unit and after it hasn't been in use for a few weeks, the first channel suddenly is dead! How high is the probability that it's really just the chip? Why should it just conk out without any reason?

250€ for replacing a 50cent opamp is a lot, on the other hand there's still the chance that there is another problem causing this malfunction and when having RME repair the unit I can be sure that it's 100% up to specs.

Now I'm even more unsure what to do... 

 

[tony hunt]

I think 250€ is more than reasonable for a one time job which is not part of a main production process.

Hitting the machine with a hammer €1,-
Knowing where to hit the machine with a hammer €10.000,-

 

[volker]

If you don't mind sending it across the alps I'll do it for a beer next time I'm in Vienna. . If the problem persists, you can still ship it to RME then.

 

[andow]

If you don't mind sending it across the alps I'll do it for a beer next time I'm in Vienna. . If the problem persists, you can still ship it to RME then.

Thank you very much! 
I'll see what my SMD-guy says and then decide...

Das Bier bekommst du schon alleine für das Angebot! 

 

[Whoops]

250€ for replacing a 50cent opamp is a lot, on the other hand there's still the chance that there is another problem causing this malfunction and when having RME repair the unit I can be sure that it's 100% up to specs.

Like Squarewave explained, and he explained very well you don't pay 250€ to replace one chip, you pay 250€ for the service, and the service includes a lot of different stuff.
It also includes the risk of damagind the board

 

[Whoops]

Get some inspiration from Louis Rossmann, he is quite good at SMD repair:

https://www.youtube.com/watch?v=mr1UVPsExiE

 

[cyrano]

I think RME swaps the entire board for 250 € and repair happens afterwards. If I'm right (I only inquired about my FF400), you also get new connectors for that price.

Transport is not included and usually the reseller in your country will require a small handling fee too.

 

[andow]

Ok, I think you guys convinced me to send the unit to RME. 

Don't get me wrong, I think 250€, no matter what the problem is, is a very reasonable offer! And since it's a lump sum I think they will just swap the board, so I'd get new connectors too!
I guess I was just hoping to save some money and the pain of packing and shipping the unit...

Thanks for your help! 

 

[Whoops]

I don't see where you got the idea that RME would swap a complete pcb, I dont think they would do that.

I would swap that opamp in a pinch, once the pcb is in front of me on the bench it takes me less than 1 minute to replace it

 

[cyrano]

I could be wrong, but that's what I've been told about repair of my FF400, that needs a few new caps, a few jacks and one FireWire connector. It is more expensive tho...

 

[Bo Deadly]

Logically it does somewhat make sense to replace the entire board because I can imagine a lot of people have problems that are actually operator error or ultimately caused by some other external forces. So if the customer gets the repaired unit and the problem still persists, RME can just say "sorry but we replaced the entire board so it cannot be a problem with the unit itself" and then they're basically clear of further liability. If they don't do it that way, the customer could just keep claiming the unit is faulty and generally be a nuisance. Meanwhile they can also do a full quality test the returned parts and work them back into the supply chain so in the long term it's probably a net credit to their balance anyway.

Of course I have no idea what their official protocol is. But RME seems like a quality company. I own and like MOTU stuff but for reasons that I cannot explain, I doubt that their QA or support is as good as RME.

 

[Whoops]

What I was saying was just  that RME replacing the complete PCB is pure speculation.