Unity gain solid state buffer - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 27th December 2012, 10:04 PM   #1
diyAudio Member
 
Piercarlo's Avatar
 
Join Date: Nov 2006
Default Unity gain solid state buffer

Hi!

In these relatively quiet days around xmas. I've conceived the unity gain buffer depicted here below.

Click the image to open in full size.

Questions is: have you yet seen some similar circuit in the past? (also not in the audio electronic field). If the answer is "yes" can you tell me vhere you seen it and from what author?

Thanks in advance
Piercarlo
  Reply With Quote
Old 1st January 2013, 03:40 PM   #2
diyAudio Member
 
Piercarlo's Avatar
 
Join Date: Nov 2006
For who want to try out the schematic proposed above here below will find a track layout for build it on a small PCB, or better again, on a breadboard. BF245A (or BF245B with an Idss below 3 mA) may be replaced with any similar N channel device with an Idss comprised between 1 to 3 mA, The JFET is used in layout with swapped source and drain (operation possible with the most of general purpose JFETs) just because more straightforward to accomodate.

Click the image to open in full size.

Happy New Year! .

Piercarlo

Last edited by Piercarlo; 1st January 2013 at 03:43 PM.
  Reply With Quote
Old 2nd January 2013, 11:32 AM   #3
diyAudio Member
 
Piercarlo's Avatar
 
Join Date: Nov 2006
Revised - Suppression of a ground loop.

Click the image to open in full size.

Happy New Year - Again! .

Piercarlo
  Reply With Quote
Old 2nd January 2013, 09:46 PM   #4
AKSA is offline AKSA  Australia
diyAudio Member
 
Join Date: Sep 2001
Location: Melbourne, Australia
I've never seen this, it is unique, congratulations!

Hugh
__________________
Aspen Amplifiers P/L (Australia)
www.aksaonline.com
  Reply With Quote
Old 3rd January 2013, 10:55 AM   #5
diyAudio Member
 
Piercarlo's Avatar
 
Join Date: Nov 2006
Quote:
Originally Posted by AKSA View Post
I've never seen this, it is unique, congratulations!

Hugh
Thanks! :-) In the next days I'll mount a pair of them for practical testing and for my use (I'm building a small integrated for headphone, in pair with a class A power amplifier derived from JLH 1969, that i named "JLH2012"). Stay tuned! ;-)

Piercarlo
  Reply With Quote
Old 3rd January 2013, 11:09 AM   #6
diyAudio Member
 
tiefbassuebertr's Avatar
 
Join Date: Jul 2005
Location: D-55629 Schwarzerden
This topology could be a good upgrade (front-end) for Andrea Cioffoli's Power Follower 99 - go to
http://www.audiodesignguide.com/my/Follower_99c.gif
Power Follower 99 sound impressions?
Power follower 99c Vs Zen
  Reply With Quote
Old 3rd January 2013, 11:23 AM   #7
Account disabled at member's request
 
Join Date: May 2006
Whats is good or special or different with regard to the performance to warrant so much complexity for just a buffer ?? It must have THD 120db below on heavy loads , extreme speed or PSRR ??.... when we can come close to that performance by using just 4 transitors and less than 1/3 the passives. Coupling caps are not well regarded in audio world either.
  Reply With Quote
Old 3rd January 2013, 12:03 PM   #8
diyAudio Member
 
Piercarlo's Avatar
 
Join Date: Nov 2006
Quote:
Originally Posted by homemodder View Post
Whats is good or special or different with regard to the performance to warrant so much complexity for just a buffer ?? It must have THD 120db below on heavy loads , extreme speed or PSRR ??.... when we can come close to that performance by using just 4 transitors and less than 1/3 the passives. Coupling caps are not well regarded in audio world either.
Who's care of these "questions"? If I wish i can replace all just with a single op-amp connected as voltage follower... If I don't try so is because i wan't try something of different. I CAN do it and I DO it! :-)

Piercarlo
  Reply With Quote
Old 3rd January 2013, 12:23 PM   #9
diyAudio Member
 
payloadde's Avatar
 
Join Date: Mar 2008
Your circuit looks similar to Maxim's BB3553 or LH0063 (used to be Burr Brown before).
http://www.datasheetcatalog.org/data.../493512_DS.pdf
These are not monolithic IC but thickfilm hybrid inside.
__________________
Judge: This court appreciates that you invented physics, Mr.Newton, but unfortunately you can't have a patent on it.
  Reply With Quote
Old 3rd January 2013, 12:39 PM   #10
Mike H is offline Mike H  United Kingdom
diyAudio Member
 
Mike H's Avatar
 
Join Date: Jul 2010
Location: East Anglia
Before getting too involved with PCB design etc., have you made a lash-up prototype of this to make sure it all works as expected? I only mention it because spice simulations normally assume that all transistors are perfectly matched clones of one another and are closely thermally linked. In fact that all components are 'perfect'. Unless you deliberately put in variations that are more like real world scenarios. (?)

Just a thought....
  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
solid state, unity gain preamp lordearl Solid State 5 29th May 2010 07:10 AM
Unity gain buffer in front of or behind TVC? KT Chip Amps 9 26th March 2006 09:02 PM
Unity gain NFB speaker-buffer Skorpio Solid State 11 30th October 2005 09:28 AM
Unity Gain Tube Buffer AKSA Tubes / Valves 41 2nd January 2004 10:11 AM
Opamp + buffer, how to bypass buffer at HF for unity gain? Christer Solid State 10 29th October 2003 06:50 AM


New To Site? Need Help?

All times are GMT. The time now is 11:29 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