SuSy Circlotron - jFET input Buffer + OPA1632 + 2SK135

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Here it is:
thank you very much.
Where you have this discovered?
A certain similarity to the AD797 should not be overlooked (see attachement). The difference is mainly the balanced buffer driving and the absence of current mirror. Current mirror was often used for unbalanced output. But I hate current mirrors. Check out therefore this:
http://www.diyaudio.com/forums/soli...screte-clone-comparison-seven-variations.html

Now I try to create some discrete versions for such a circlotron with voltage gain
 

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> the fully differential BF862 discrete opamp

I have one in DIP12 package, and sounds better than OPA1632, but have thermal drift which is too large for my taste.
So I will not post. But as clever as you are, you will figure out from my DIP8 discrete opamp. Patrick
This OP-Amp from follow URL as fully differential opamp?
http://www.diyaudio.com/forums/pass-labs/120445-pass-discrete-opamp-dip-8-package.html
What means the term "too large" in voltage values regarded your observed thermal drift?
 
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TI had the good taste to license the patent.
:cool:

Yes, if you mean the US patent 5376899:
http://www.diyaudio.com/forums/pass-labs/77568-texas-instruments-licenses-pass-patent.html
http://www.diyaudio.com/forums/pass...m-results-pass-x-series-us-pat-5376899-a.html

Therefore a new approach was realized from you (see attachement). I strongly suspect that this is also a Circlotron, similare than the mentioned version from post #1, but a discrete version - isn't it?
(have a look also about post #2 about
http://www.diyaudio.com/forums/pass-labs/158212-mr-pass-anything-ces.html )
 

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which commercial brands uses this topology in the meantime?
http://www.diyaudio.rs/uploads/monthly_12_2009/post-20-126057485619.gif

Hello Andreas. US 5,376,899 was granted on Dec. 27, 1994 to Pass. It has expired [1994+17 years = 2011]. Mr. Pass has already profited from his invention by exclusively selling the amps it taught, and via licensing. Are you asking about power amps other than those made by Pass, or ICs [by TI or other] which are used to support the commercial practice of the patent?
 
> the fully differential BF862 discrete opamp

I have one in DIP12 package, and sounds better than OPA1632, but have thermal drift which is too large for my taste.
So I will not post. But as clever as you are, you will figure out from my DIP8 discrete opamp.

;)


Patrick

Only in cases of DC coupling this is an issue. I cases with single supply (neg polarity = GND), capacitors in the signal pad and creating a Vref node a small thermal DC drift doesn't matter.
Please let me know the URL here on diyaudio, where was upload the schematic therefore - thank you.
 
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