Super Regulator

Switches things on and off again
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Andrew,
Editors note: correction 2 posts down...
Both the A and B versions can be used with no impact on performance. If you have to buy them, buy the A version because you'll probably use some of them in other projects, and why not go for the highest beta.

As you probably read in the article you need to use another ref anyway for output voltages below 6.9V. The LM-4040 series offers all kinds of voltages and are a good choice. But undoubtedly there are others.
The spec to look for is low noise, rather than accuracy. The output voltage accuracy really is almost of no consequence here.

Jan
 
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By using different opamps, can the available voltage range be extended higher? Some possiblities were mentioned in the Linear Audio thread, I believe.

The opamp is supplied from the output voltage so there's your limit as far as output voltage is concerned. I think max 44V (+/-22V) is the limit for available opamps, in that case you don't want to go higher than 40V or so.

Apart from the obvious voltage rating for the capacitors, you should change D2/D7 to get the opamp output back to half the Vout for best performance, as well as change the D5/D10 series resistor to get the current through them back to about 1.5 to 2 mA.

Jan
 
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Thank you. Looking for about 35-36V

Yes that should be no problem, but you need a higher voltage opamp, a regular one with max +/-18V supply is cutting it a bit close for my taste.
IIRC the NE5534 can handle 44V total and would work well here.

Edit: the NE5534 is spec'd for 40V total supply max, should be OK.

Jan
 
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it is confusing
please correct

do you mean ... if buying, get B or C if possible, but A would be ok too, in one side ?

A would be OK in either side. It's just what I had, the performance is only very weakly depending on that, it's not measurable.
But I will change the schematic and the BoM.

Edit: Done.

Jan
 
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Correct. Please re-read post #3 & #5.

Jan
Jan,
the sch shows a grade A and yet in post5 you correct what you said in post3 where you said C is better than B, even though you had B fitted in both locations in your own build.

Why show A when you tell us that A is the least preferred of the three grades.

Either, the sch should not show any grade and builders will use what they can find, or the sch shows alternatives (i.e. grades A and B) without comment.
Or, the pdf explains that there is a preferred and that all grades are acceptable.

As is, the sch is confusing, because it appears one must be B grade and the other must be A grade.
 
No the max per regulator is somewhere below 40V (depending on the opamp).
With a pos and a neg reg (there's one pos and one neg reg on one PCB) you can go up to +/-36~38V.

Jan

But in post #7 you said,

"The opamp is supplied from the output voltage so there's your limit as far as output voltage is concerned. I think max 44V (+/-22V) is the limit for available opamps, in that case you don't want to go higher than 40V or so."