John Curl's Blowtorch preamplifier part II - Page 3509 - diyAudio
Go Back   Home > Forums > Member Areas > The Lounge

The Lounge A place to talk about almost anything but politics and religion.

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 14th February 2013, 08:53 PM   #35081
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
Read the Solomon article and all will be revealed!
  Reply With Quote
Old 14th February 2013, 09:06 PM   #35082
diyAudio Member
 
Esperado's Avatar
 
Join Date: Jul 2011
Location: France
John, too much work to translate hundreds of pages, not responding directly to my questions, for the little i had read, even included in my question considering the all closed loop behavior.
Reformulating with an image, reducing gm of the input stage increase the efficiency of the ABS, but not the tire's grip.
__________________
Ultimate Protection and more.The Only Source of Knowledge is experience, everything else is just information” ©A. Einstein

Last edited by Esperado; 14th February 2013 at 09:16 PM.
  Reply With Quote
Old 14th February 2013, 09:23 PM   #35083
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
I'd wager "differential mode."
__________________
You might be screaming "No, no, no" and all they hear is "Who wants cake?" Let me tell you something: They all do. They all want cake.- Wilford Brimley
  Reply With Quote
Old 14th February 2013, 09:32 PM   #35084
diyAudio Member
 
Esperado's Avatar
 
Join Date: Jul 2011
Location: France
Quote:
Originally Posted by SY View Post
I'd wager "differential mode."
Witch gives some advantage to bridged amplifiers.
__________________
Ultimate Protection and more.The Only Source of Knowledge is experience, everything else is just information” ©A. Einstein
  Reply With Quote
Old 15th February 2013, 12:02 AM   #35085
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
Pages 9 and 10 Esperado. You might just learn something.
  Reply With Quote
Old 15th February 2013, 12:50 AM   #35086
diyAudio Member
 
Speedskater's Avatar
 
Join Date: Sep 2002
Location: Lakewood, Ohio
Quote:
Originally Posted by Pano View Post
I thought it was "Dr. Lube"
Maybe it should be Dr. Cremlon, as another branch (one of hundreds) of his company now markets that product.
__________________
Kevin
  Reply With Quote
Old 15th February 2013, 01:21 AM   #35087
RNMarsh is offline RNMarsh  United States
diyAudio Member
 
RNMarsh's Avatar
 
Join Date: May 2012
Location: 2457 Cascade Trail; Cool, CA. 95614
Quote:
Originally Posted by SY View Post
I'd wager "differential mode."
yes! So now with that knowledge, how do you design a power supply that minimizes diff-mode changes?
What characteristic would it have and what type of circuit has that characteristic?

-Richard
  Reply With Quote
Old 15th February 2013, 01:30 AM   #35088
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
Here is page 9 (out of 20) of probably the best app. note on amplifier design that I have ever found. The top equation (20) is the KEY EQUATION for understanding slew rate and how to improve it. The left hand term is the definition of Slew Rate, or dv/dt
is proportional to 1/Gm of the input stage. The other terms are related to the input stage operating current and the gain bandwidth of the amplifier.
Attached Images
File Type: jpg Picture 83.jpg (286.7 KB, 154 views)
  Reply With Quote
Old 15th February 2013, 01:32 AM   #35089
diyAudio Member
 
Esperado's Avatar
 
Join Date: Jul 2011
Location: France
Quote:
Originally Posted by john curl View Post
Pages 9 and 10 Esperado. You might just learn something.
The truce was short-lived.
As i said, i had read-it, ant nothing new, neither respond my question.
Yes, degeneration increase slew-rate of the input stage, thus a part of the delay. But the issue*is* the closed loop and it does the contrary of what we want : each stage faster than the previous one inside the loop.
You prefer open loop topology and you seem to allow artificial enhancement of slew rate *by the feedback* ? Seems contradictory.
CFA is a way to achieve high bandwidth of the first stage, *by design*. It does not replace having a fast power stage, where current is most demanded and load non mastered..
__________________
Ultimate Protection and more.The Only Source of Knowledge is experience, everything else is just information” ©A. Einstein

Last edited by Esperado; 15th February 2013 at 01:43 AM.
  Reply With Quote
Old 15th February 2013, 01:34 AM   #35090
diyAudio Member
 
Esperado's Avatar
 
Join Date: Jul 2011
Location: France
Quote:
Originally Posted by RNMarsh View Post
how do you design a power supply that minimizes diff-mode changes?
Virtual ground ? (Does not work so good because distortion.).
An other solution (don't know the word in English) is crossed feedback between the two sides.
__________________
Ultimate Protection and more.The Only Source of Knowledge is experience, everything else is just information” ©A. Einstein

Last edited by Esperado; 15th February 2013 at 01:53 AM.
  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



New To Site? Need Help?

All times are GMT. The time now is 11:45 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