Super Regulator, collecting the facts

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Well, here's a much soldered over proto-type -- this one omits the clamp diodes on the AD825's -- I did get a wonky LM329DZ which wouldn't allow the SMT version to start-up -- replaced it and now works fine. The positive regulator has the LM317 pre-regulator, while I took the negative pre out for testing purposes. In the final version I think that I can save about 33% of the real estate by scrunching things up.

This one uses R1206 1K resistors for the error sense -- in the next go around they will be R2010.

Three are no bypass caps in either of these, no oscillation problems at all. I do use 499R to decouple the inverting input of the opamp.

Oh, and you can see where there was an error on the PCB -- had to patch up with some wire-wrap wire.

Edit -- the high current traces pass along the edges of the board. The grounds all intersect in the center.

An externally hosted image should be here but it was not working when we last tested it.
 
Here's a comparison of the straight AD797AN SuperRegulator with a Pre-Regulated Version -- using an LM337 -- I guess it's pretty convincing -- I still want to do this with the HP3403C for 10Hz to 100kHz. FWIW when I repeated the AD797 tests the values still come up the same so there isn't some environmental wonkiness going on.

An externally hosted image should be here but it was not working when we last tested it.
 
Jack, some time has gone now, any conclusions? Does the board work alright?

My all SMD regulator works pretty good. The difference is that I used a 1 A SOT223 transistor.

jsr02r0_overview.jpg
 
Khron said:
Mr jackinnj , would you mind if I asked you to post/attach the schematic / PCB / silkscreen for the through-hole version of the super-reg?

(For DIY purposes - powering some active crossovers)

The boards are available from AudioXpress' webstore -- Old Colony Sound -- for $24.95. Here's a link: http://www.audioxpress.com/bksprods/PCBCTB.htm
For the noise testing I used the Old Colony boards and through-hole parts.

PA -- looks good -- I found that the R2010 resistors were best for the error sense circuit -- I had used R0805 originally. Why not solder in an AD797AR and see how it compares with the AD825 -- and in spite of admonitions against, I found that the LT11115 worked quite well on the Old Colony board.

My smt board works very well -- it incorporates the LM317 pre-regulation -- I have it working in the modded Crown IC150a preamp.
 
Well, with all due respect, unless you have some sort of financial aggreement with AudioXpress, i'd much rather etch and drill the pcb's myself :)

Plus, that's quite pricey for a few sq.in of circuit board, at least for my pocket...

PS: regarding the opamps used, apart from the GBW, low noise, low offset, what other minimum requirements would there be? (like slew rate etc)
 
peranders said:

Somewhere between 500-1000 mW. Since I have a groundplane I'll get cooling also. I haven't tested the absolute limit.

Mine dissipates about 800 mW -- the D-Pak is about 50% more efficient than the SO-223 package and is a pretty close analog to the D44 and D45 used by WJ and JD in their designs -- but in both cases the required surface area under the chip is pretty small -- at least according to National Semi AN-1028.
 
Sing The Glory of AD797 - One of the best Op-Amps ever designed

ALW said:
The AD797 is a remarkable chip,
but not in this reg.
---
Not one of my AD825-based units has ever oscillated


ALW
I agree with first part of yur statement - because it is for me TRUE!

jackinnj
great work and excellent investigations.


I also can tell, for anyone not knowing already, there is not many that have succh nice test-gears, (some of it he has built himself) as jackinnj.
Me lineup has not!
... but I many times can recoginze a good circuit, by the sight of it.
AD797 is such a circuit.
Anyone that has followed my works and postings here, would know about my likings of AD797.

:) Do a forum search: lineup AD797



An externally hosted image should be here but it was not working when we last tested it.


In this special Super Regulator application
it looks like AD825 does well,
but both AD797 and LT1055 does better, by one level.



May I also remind of one Topic I started, where I published a discrete Clone of AD797.
Those who can understand what is a good Amplifier
has already downloaded my schematics ;)

the AD797 chip, has got it's limitations:
mainly:
- Supply Voltage upper limit
- Ouput Drive Current limit, comes from how much heat a DIL8 can take

... :cool: while my Clone and any customly design AD797-Clone does not need to have
such restricted performance.
-------------------------------------------------------------------------


;) Keep on this Super Regulator work boys and girls!
( I see jackinnj is most probably a dear Lady )
and .... peranders is a very good man in Low Noise Extreme apps.
( See for example peranders Extreme Low Noise RIAA Amp )


Couldnt be a better Team here,
for making The Ultimate Best Regulator ... ever


Regards
lineup
:)
...................................................................

APPENDIX A.
Amplifiers >Solid State > AD797 Clone people! Who can make a better one.

http://www.diyaudio.com/forums/showthread.php?threadid=92094


lineup said:
12th December 2006
Everything tells me, that AD797 is not only a very good operational amplifier
The topology used has got to be something extremely good!
----
A few details from me, for those who want to try to make a better AD797 Clone.
... but I am not sure anyone could do this better than myself
... maybe get some similar results, but not better, I doubt.
----
My circuit is in attachment and follows the AD797 schematic
 
Re: Re: Sing The Glory of AD797 - One of the best Op-Amps ever designed

jackinnj said:

No, it's just that Carol Beer is my favorite actrix.

There has been 'a pair of boys' on our TV up here.
It is two crazy english boys, and they dresses in Womans clothes.
Often also one of them is sitting in a wheel chair.

I wonder, maybe 'Carol' is in that English TV-serie?
Anyway, it is almost as fun & good as 'Monty Python's Flying Circus'
... another totally absurd English invention.


Regards
lineup - not english, - but I fancy them Crazy English :clown:
like: John Cleese - my good what Childish Man ;D
 
peranders said:
A tube based sort of super regulator, an article by Mr. Bob Pease.

http://www.elecdesign.com/Articles/Index.cfm?ArticleID=1509

I think it look like an super regulator if the basic concept is considered as an voltage reference powered from the output and an error amp also powered from the output.
What do you say guys, tube dudes? Can this circuit be labeled as "super regulator"?
 
If anyone already has any scope photos (or just data) of transient testing with a dynamic load, such as when drawing fast-edged current steps that rise from near minimum to near maximum and fall from near maximum to near minimum, or whatever else you might have, perhaps something that might be a more-appropriate transient test, I would be interested in seeing them.
 
gootee said:
If anyone already has any scope photos (or just data) of transient testing with a dynamic load, such as when drawing fast-edged current steps that rise from near minimum to near maximum and fall from near maximum to near minimum, or whatever else you might have, perhaps something that might be a more-appropriate transient test, I would be interested in seeing them.

I don't have scope, but I do have a friend owning one, so if you explane me step by step how and what I need beside scope, maybe I can performe same testing in future (emphasize on maybe and future), cos I've never deal with scope and stuff beffore.

AndrewT said:
Hi Aparatus,
give us more, I'm banging the spoon.;)

Will do I hope, but what exatly you want Andrew?

...and my apologize to Mr. Walt Jung 'cos I put his name on thing which he has no involvement in. Anyway, I will remove his name if I ever produce some more PCBs, 'cos I have deep respect for him (thx Per-Anders;) )
 
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