How to measure if the BB opa627 is real

[daniloreyes]

Hi,

Many people are counterfeiting the Burr Brown TI opa627.

Anyone knows how to measure if the BB opa627 is real?


Any ideas?

I know that many buy it and then when instaling say it has to be real because the sound improved a lt, but that is not a way because they are replacing a really cheap part, and if the one being installed is better .

On the same line,
Is there a way to see which is better the opa627A or the opa627B ?

Thanks

[analog_sa]

Easy Just measure noise and slew rate. Providing you are lacking the equipment but possess the ears, you can always compare the potential fakes to a proven "real" chip. And if you cannot hear a difference, does it really matter fake or real?

[jitter]

Originally Posted by daniloreyes

Hi,

Many people are counterfeiting the Burr Brown TI opa627.

Anyone knows how to measure if the BB opa627 is real?


Any ideas?

I know that many buy it and then when instaling say it has to be real because the sound improved a lt, but that is not a way because they are replacing a really cheap part, and if the one being installed is better .

On the same line,
Is there a way to see which is better the opa627A or the opa627B ?

Thanks

Most of us would lack the equipment to do that (I do). But if you had a function generator and an oscilloscope that exceed the bandwidth of the OPA627 (at gain 1, that's "only" 16 MHz), you could measure the large and small signal responses and compare them with those in the datasheet. The circuits needed are also in there.
I don't think you could do noise measurements at home.

About differences between the A and B-versions: I know that in the A-version a certain instrument the company I work for assembles and tests (I won't be more specific), during a noise measurement there would be far more drift of that noise-floor than with the B version (caused by offset voltage drift which is much better in the B-versions).
But "far more" would only be in the range of nanoAmps into a 1k load, so I seriously doubt that would be audible especially since there is no difference in frequency response between A and B-versions.