Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Using the LM317 with higher voltages
Using the LM317 with higher voltages
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 28th October 2019, 02:25 PM   #11
carlmart is offline carlmart  Brazil
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
I'm trying to follow certain findings published in The Audio Amateur in the '90s about the impedance curve of regulators. Not many regulators publish that data, Texas does not on the 783, for instance.

Yes, many regulators, like the LT1083, do not have a negative version, so you need to have separate secondaries on the transformers, wiring them after the regulation and using the ground on one regulator as negative output.

But I would like to have an advice on how to implement my regulator with the 317 or 1083 if possible, just warning what would remain unprotected, like short-circuiting the output, which would be quite rare to happen and would allow me to use them.

My main concern is protection for what I am to power with those regulators.
  Reply With Quote
Old 29th October 2019, 01:36 PM   #12
Kay Pirinha is offline Kay Pirinha  Germany
diyAudio Member
 
Kay Pirinha's Avatar
 
Join Date: Oct 2011
Location: Somewhere in Germany
The original 1980 Maida regulator or the 21st century Maida are your solutions!
Best regards!
__________________
„The ships hung in the sky in much the same way that bricks don't.“
(Douglas Adams)
  Reply With Quote
Old 29th October 2019, 05:26 PM   #13
carlmart is offline carlmart  Brazil
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
Exxxxxxtremely complicated!!! I want something simpler but high quality, preferably with a proven regulator like the 317/337.

If I wanted something like the Maida I would go with a Sulzer or Jung high voltage regulator. It would be just a question of finding a high voltage IC, and that would be hard to beat.

Those are proven designs, both technically and audio wise.
  Reply With Quote
Old 29th October 2019, 06:45 PM   #14
rsavas is online now rsavas  Canada
diyAudio Member
 
Join Date: Aug 2012
Location: Ontario
You can't have it both ways.
I do not know why you want to complicate the issue with wanting 'impedance curve of regulators" If you want them, measure them yourself.
Quote:
My main concern is protection for what I am to power with those regulators.
What kind of protection?
OVP, use a SCR crowbar.
OCP use a fusible R or an actual fuse in front of or use a current limiting circuit in front of the reg.
  Reply With Quote
Old 30th October 2019, 12:49 PM   #15
carlmart is offline carlmart  Brazil
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
The protection I mean is for overvoltage at the output.

Which high voltage IC would anyone suggest to use on a HV Jung/Didden regulator?

Some time ago one was suggested to me, but I forgot which it was.
  Reply With Quote
Old 30th October 2019, 12:55 PM   #16
carlmart is offline carlmart  Brazil
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
The only I could find googling was this one:

http://www.ti.com/product/OPA454

But current is too low to be used on a power amp, even in the low current stages.

Neither if it would be a good choice for superregulator.
  Reply With Quote
Old 30th October 2019, 12:56 PM   #17
rsavas is online now rsavas  Canada
diyAudio Member
 
Join Date: Aug 2012
Location: Ontario
Quote:
The protection I mean is for overvoltage at the output.
OVP, use a SCR crowbar.
Show me a " HV Jung/Didden regulator" schematic
I found this HV dual tracker from Pioneer a while ago.
Attached Images
File Type: png Pioneer_M-Z1 tracking regulator.png (450.8 KB, 329 views)

Last edited by rsavas; 30th October 2019 at 01:05 PM.
  Reply With Quote
Old 30th October 2019, 02:51 PM   #18
sgrossklass is offline sgrossklass  Germany
diyAudio Member
 
Join Date: Nov 2004
Location: Germany
Quote:
Originally Posted by rsavas View Post
I found this HV dual tracker from Pioneer a while ago.
These used to be quite common at the time. This one would seem to be high performance (thumbs up for the current source and AC unity gain) but has a few quirks:
1. I wonder why they used a CFP for a pass transistor when there was ample voltage headroom?
2. Also, why this peculiar voltage adjustment setup with one resistor chain for both and an extra pot for symmetry? Most looked more like this (from a Sansui AU-717):
Click the image to open in full size.
I.e. the the -reg is basically an inverting amplifier with a DC gain of roughly -1 (allowing for a -0.6 V offset, occasionally also provided by a diode so they could use equal resistor values - it's not like utmost precision is required here), based on the +reg doing its own thing.
  Reply With Quote
Old 30th October 2019, 05:44 PM   #19
rsavas is online now rsavas  Canada
diyAudio Member
 
Join Date: Aug 2012
Location: Ontario
The Pioneer design was out of the norm for sure, that is why I posted it because I saw it was different and from one of their TOTL models at the time, M-Z1.
I can not answer your ?'s as to why it was done that way, only speculation. Would need to simulate to figure out performance but I will leave that to the op.
This Sansui design was more common for sure. No protection other than fuses. The tracking saved them a zener.
  Reply With Quote
Old 1st November 2019, 05:30 PM   #20
carlmart is offline carlmart  Brazil
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
OK, I don't have here the high voltage regulators suggested in The Audio Amateur, as I am not at home.

The ones I was referring to, based on the 3X7 regulators, were used for an Erno Borbely 60W amp mod, and also for a Hafler DH220. Perhaps someone might remember them.

But I was thinking of a different, more sophisticated and more expensive approach: a high current Jung/Didden superregulator.

Some time ago I had also asked here about such a regulator, and Jan Didden had suggested a high voltage opamp that I can't remember which it was.

Looking around for high voltage suitable opamps, the only one I could find was this one:

OPA552PA Texas Instruments | Integrated Circuits (ICs) | DigiKey

Unfortunately I would need a higher voltage chip, as the amp I would use it for would need +/-67v. The OPA552 can only go up to +/-30v, that means +60v should be the maximum input voltage, which would mean less than 55v DC for the output. Am I correct?

It's a pity I never saw a voltage regulators comparison that included the Kit Ryan's regulator used for the Adcom GFA555. Here it's the high current version they used for it, but Nelson Pass used it to regulate the low current stages on his A75 power amp.
Attached Images
File Type: gif Kit Ryan power supply.gif (20.3 KB, 207 views)
  Reply With Quote

Reply


Using the LM317 with higher voltagesHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Advantage in designing an amplifier to except higher than average input voltages? shredhead Solid State 10 2nd March 2015 03:26 PM
Is it true that the higher the BL of a subwoofer, the higher its lowest playable... 454Casull Subwoofers 16 19th March 2004 05:28 PM
BOZ off higher voltages? JoeBob Solid State 5 16th December 2002 05:58 AM
BOZ at higher voltages+funky PS anyone? chiggy Pass Labs 3 10th September 2002 02:24 AM
Super-power amps - higher current better than higher voltage Circlotron Solid State 34 28th June 2002 05:01 AM


New To Site? Need Help?

All times are GMT. The time now is 12:30 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki