Regulated +80V Supply .... - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies

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 19th July 2012, 04:33 AM   #1
diyAudio Member
 
Join Date: Apr 2012
Location: Germany, Ruhr Area
Default Regulated +80V Supply ....

Gentlemen,

For my Project I Need a 80v regulated Supply. I have a double rail +80V/0V PSU.

I'm only a mechanical engineer and Need a prinicipal Sketch how it Looks like ...

See also here: DIY Project - Nytech CPA602 today ...

Thanks for your help ...
  Reply With Quote
Old 19th July 2012, 06:29 AM   #2
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Looking at your other thread I'm assuming the 80 volts regulated is at very low current ?

If so a simple zener regulator is ideal (3 series connected 27 volts zeners) fed via a resistor. A small cap is placed across the three zeners to maintain a low impedance clean supply. The resistor value is calculated by knowing the voltage feeding the chain (which has to be higher than 80 volts) and the max current the regulator has to supply.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 19th July 2012, 07:42 AM   #3
diyAudio Member
 
Join Date: Apr 2012
Location: Germany, Ruhr Area
Quote:
Originally Posted by Mooly View Post
Looking at your other thread I'm assuming the 80 volts regulated is at very low current ?

If so a simple zener regulator is ideal (3 series connected 27 volts zeners) fed via a resistor. A small cap is placed across the three zeners to maintain a low impedance clean supply. The resistor value is calculated by knowing the voltage feeding the chain (which has to be higher than 80 volts) and the max current the regulator has to supply.
Yes I think so, it's at ver low current as it is to supply the VAS. Can I found somewhere a principal schematic?

Or does it makes sense to use a regulater like the LM317 ...?
  Reply With Quote
Old 19th July 2012, 07:47 AM   #4
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
I'll draw it... give me a few minutes.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 19th July 2012, 07:54 AM   #5
diyAudio Member
 
KatieandDad's Avatar
 
Join Date: Nov 2011
Location: UK
Quote:
Originally Posted by NRWler04 View Post
Yes I think so, it's at ver low current as it is to supply the VAS. Can I found somewhere a principal schematic?

Or does it makes sense to use a regulater like the LM317 ...?
You can use an LM317 with GREAT CARE. The max In-Out voltage is only 40V.

The zener chain as suggested above will do the job in this case.
  Reply With Quote
Old 19th July 2012, 07:58 AM   #6
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Like this. Resistor is calculated with ohms law to allow a few millamps to flow in the zeners.

eg, 100 volt unregulated. R=V/I so R=(100-81)/0.01 which is 1900 ohms. Use 1800 ohms as preferred value.

So that allows 10ma to flow in the zeners. The load (the amp) draws from that 10ma. If the load were 5ma then the zener current would reduce to 5ma with the above values. Always allow at least around 5 ma to flow in the zeners at all times.
Attached Images
File Type: png PSU.png (25.6 KB, 496 views)
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 19th July 2012, 08:51 AM   #7
diyAudio Member
 
Join Date: Apr 2012
Location: Germany, Ruhr Area
Wonderful :-) I'll setup a schematic for the modified PSU today evening and will post the schematics.

There are also regulators available with higher voltage .... e.g. TL783 from Texas Instruments ....
  Reply With Quote
Old 19th July 2012, 11:16 AM   #8
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
The zener type shunt regulator takes some beating with its low output impedance. I think they will give the cleanest possible supply.

The TL783 is an interesting choice but not without precautions. This type of regulator needs a minimum load applied at all times in the region of 15 ma (absolute minimum) so that could make it more inefficient than the zeners.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 19th July 2012, 12:03 PM   #9
diyAudio Member
 
Join Date: Apr 2012
Location: Germany, Ruhr Area
I'll do it with the zener shunt regulator .... And again I learned something :-)
  Reply With Quote
Old 19th July 2012, 12:09 PM   #10
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
I was just looking at the circuit for the Nytech.

There's nothing to stop you using a "double" zener regulator. Use an 80 volt one as mentioned and add a 50 volt one for the bias network fed from the 80 volt one.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote

Reply


Hide 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
3 Pin regulated supply VS zener based supply KevinLee Solid State 3 15th September 2008 02:40 PM
Best regulated power supply. JC951t Digital Source 20 14th November 2007 09:04 PM
Nakamichi PA-7E/ 80V DC Voltage of main Supply deq2496 Solid State 9 12th January 2007 02:50 PM
Regulated power supply akunec Chip Amps 3 5th November 2006 10:27 AM
Class D Amplifier Power Supply Design -> 12,5 A @ +/-80V = 1000W selfservice Class D 22 1st September 2006 01:20 PM


New To Site? Need Help?

All times are GMT. The time now is 04:49 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2