The NE5532P are from Farnell, i expect they are not fake.
Don't have many time to see the frequency, the temperature raise too fast Here is the output buffer entry after this Opamp.
They will be fine if from Farnell. So you need to do some basic tests. If its getting really warm then check the current consumption... 5532's do get a little warm. And you really need to use an oscilloscope to see what is actually happing.
If the chip is really hot within seconds then something drastic is occurring.
The output buffer is shown as inverting... so the + input needs to be ground referenced.
The first diagram looks OK but as a test, if you isolated the four caps then it should 100% be stable. If it still got hot and didn't work then you have to suspect the opamp.
If the chip is really hot within seconds then something drastic is occurring.
The output buffer is shown as inverting... so the + input needs to be ground referenced.
The first diagram looks OK but as a test, if you isolated the four caps then it should 100% be stable. If it still got hot and didn't work then you have to suspect the opamp.
Oups
sorry, here is the good sheme of my output buffer.
I will make some measurements soon but the thermal runaway is fast... i must physically prepare myself to be fast
The scope is flat on the entry 
and the decoupling caps are Kemet R82 0.1µF MKT on each rail.
http://www.kemet.com/Lists/ProductCatalog/Attachments/532/KEM_F3101_R82.pdf
Here is the scope capture
(at the NE5532P pin)
Amplitude : 5V
Time : 2µS
...
and the decoupling caps are Kemet R82 0.1µF MKT on each rail.http://www.kemet.com/Lists/ProductCatalog/Attachments/532/KEM_F3101_R82.pdf
Here is the scope capture
(at the NE5532P pin)
Amplitude : 5V
Time : 2µS
...
Yes,
Phase reversal due to the input capacitance
i've tried 100pF... don't work
... Another 100pF
fixed with 200pF 
Thx.
i've tried 100pF... don't work
... Another 100pF
Thx.
So are we done then ?
Yes.
We don't often write how it can be fun to make circuits and experimentations
and it is fun really sometimes
the circuit is stable and the gain is ok ! (was not with the TL072) with a 220pF styrofex cap soldered directly on PCB tracks and very close to the chip.
now the ASP board is equipped with MKS, MKP, MKT, NPO and Electrolytic caps
I've forget Tantalum
We don't often write how it can be fun to make circuits and experimentations
and it is fun really sometimes the circuit is stable and the gain is ok ! (was not with the TL072) with a 220pF styrofex cap soldered directly on PCB tracks and very close to the chip.
now the ASP board is equipped with MKS, MKP, MKT, NPO and Electrolytic capsI've forget Tantalum
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