AD Vs BD Modulation in Class-D - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

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 4th February 2006, 04:51 AM   #11
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Hi Andy,

Then Stay Tuned..........

K a n w a r
  Reply With Quote
Old 24th November 2007, 11:43 AM   #12
Account Disabled
 
Join Date: Apr 2007
@Workhorse

I think Ecler is making Class-BD amps.....

www.ecler.com
  Reply With Quote
Old 25th November 2007, 03:27 AM   #13
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Quote:
Originally posted by Iyremenko
@Workhorse

I think Ecler is making Class-BD amps.....

www.ecler.com
Thanks for the link i have just read there white paper on Tri-level amazing facts.....
  Reply With Quote
Old 17th May 2010, 08:59 AM   #14
ravaz is offline ravaz  Malaysia
diyAudio Member
 
Join Date: Jun 2009
This document may helps you:

http://focus.ti.com/lit/an/sloa119a/sloa119a.pdf

As for my understanding BD requires smaller components and has better EMI, having the only drawback of being more dificult to calculate.




Regards,

Ravaz
  Reply With Quote
Old 17th May 2010, 02:12 PM   #15
savu is offline savu  Romania
diyAudio Member
 
savu's Avatar
 
Join Date: Feb 2007
Location: Cluj - Napoca
Send a message via MSN to savu Send a message via Yahoo to savu
to Ravaz:

Thanks a milion for sloa199a

best regards,
__________________
1'st rule of chess:
The only way to get smarter is by playing a smarter opponent.
  Reply With Quote
Old 18th May 2010, 04:53 AM   #16
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Quote:
Originally Posted by ravaz View Post
This document may helps you:

http://focus.ti.com/lit/an/sloa119a/sloa119a.pdf

As for my understanding BD requires smaller components and has better EMI, having the only drawback of being more dificult to calculate.




Regards,

Ravaz

BD requires more components than AD modulation.
  Reply With Quote
Old 18th May 2010, 09:32 AM   #17
81bas is offline 81bas  Germany
diyAudio Member
 
Join Date: Jan 2006
Location: Kiel
About EMI and AB/AD modulation:
http://www.hypex.nl/docs/AES124_Masterclass_Putzeys.pdf, pages 81, 82, 83
  Reply With Quote
Old 18th May 2010, 12:56 PM   #18
Eva is offline Eva  Spain
diyAudio Member
 
Eva's Avatar
 
Join Date: Oct 2003
Location: Near the sea
Send a message via MSN to Eva
Who would trade overall EMI performance for eliminating carrier residual only when there is no signal?

Carrier residual applied to speakers is completely harmless. EMI can potentially disturb any piece of electronics around.

Class BD means "wrong design goals". Low EMI should be the first goal.
__________________
I use to feel like the small child in The Emperor's New Clothes tale
  Reply With Quote
Old 18th May 2010, 02:23 PM   #19
diyAudio Member
 
Join Date: May 2010
Default BD modulation

The reason people are interested in BD comes from Delta-Sigma convertors. If you can use a three level output you can decrease quantization noise by 6dB. You also get to utilize the dead time instead of it being your enemy. One problem with BD though is that you lose the inherent linearity of a two level system. The distance between high and low level in a two level is what it is but in a three level the distance (magnitude) from "zero" to high level will be different than from "zero" to low level or negative. This introduces nonlinearity. Otherwise, the BD is kinda neat when you are trying to do a more advanced noise shaped amp, especially if it's a true digital amp.

Cheers
  Reply With Quote
Old 19th May 2010, 10:26 AM   #20
diyAudio Member
 
Join Date: May 2002
Location: Switzerland
I think Kanwar is talking about what is described in Bruno's paper (which was mentioned some posts before) and not some three-state amp that is using an "open" state.

This has one advantage: The apparent switching frequency and also the actual sampling frequency is twice as high for a given carrier frequency when you use a carrier-based amp. Therefore you can use more loop gain.

Regards

Charles
  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
Flux modulation 454Casull Multi-Way 71 2nd November 2011 11:21 PM
How many modulation methods in Class D amplifier ? xuhaoz Class D 20 5th December 2006 04:15 AM
Alternative modulation schemes for class d amps Nirav Desai Class D 6 10th January 2005 09:26 AM
Class D Modulation Scheme pokka Class D 7 15th December 2004 07:33 PM
new class D modulation method? sfx Class D 12 6th October 2004 07:02 AM


New To Site? Need Help?

All times are GMT. The time now is 05:06 AM.


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