LM4651/LM4652 class D amps - 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 7th June 2005, 04:56 PM   #1
diyAudio Member
 
lawbadman's Avatar
 
Join Date: Mar 2003
Location: St. Catherine, Jamaica
Default LM4651/LM4652 class D amps

Hello all,

It seems that these chips have been mentioned a few times but topics came to no real conclusion, so now I will have a go at it.

I want to build a few LM4651/LM4652 class D amps based on the audio application diagram in the datasheet (page 24 and 25). Can someone make the PCBs for me, or know were I can get PCBs made in the US for a good price, and done within a week or so?

Also I was thinking that I could just use perf board since the circuit is not very complicated, but I am a bit worried since high frequency is involved. So is it ok to use perf board or not?

Any suggestion is welcome.

http://www.national.com/pf/LM/LM4651.html
http://www.national.com/appinfo/audi...19,968,00.html


Thanks
Lawrence
__________________
<a href="http://www.danasoft.com"><img src="http://www.danasoft.com/sig/lawbadman.jpg" border="0"></a><div style="font-family:arial,sans-serif;font-size:11px;"><p>Sign by Danasoft - <a href="http://www.danasoft.com">For Backgrounds and Layouts</a></p></div>
  Reply With Quote
Old 8th June 2005, 01:07 AM   #2
SSassen is offline SSassen  Netherlands
diyAudio Member
 
SSassen's Avatar
 
Join Date: Mar 2005
Location: Edam, The Netherlands
Wouldn't it be much simpeler to use the Philips TDA8920? It is also available in a 23-pin, single row DIP style packaging and requires very little external components. Furthermore the BTL configuration will deliver up to 150-watts, enough for most applications I'd say. Oh, and in the spirit of DIY I suggest you also attempt designing a PCB yourself, else you're really taking the Y out of DIY.

Best regards,

Sander Sassen
http://www.hardwareanalysis.com
  Reply With Quote
Old 8th June 2005, 03:00 AM   #3
diyAudio Member
 
lawbadman's Avatar
 
Join Date: Mar 2003
Location: St. Catherine, Jamaica
Hi SSassen,

The TDA8920 was at the top of my list of amp to choose from, but I cant find any online store that sells it. If you know of any let me know.

My problem is that I need PCBs by next week and I have no experience with PCB design, plus the amp is class D with crazy high frequencies so it might be a bit difficult for my first try, and I have no scope.

But if you know of any other good high power (very important), inexpensive class D amps let me know.

I was thinking about just going with a regular LM4780 but I really dont want to be bothered with getting rid of all the heat it produces, since I would use 4 chips (parallel each chip), for PA and subwoofer use, thats why I want class D.



Thanks
Lawrence
__________________
<a href="http://www.danasoft.com"><img src="http://www.danasoft.com/sig/lawbadman.jpg" border="0"></a><div style="font-family:arial,sans-serif;font-size:11px;"><p>Sign by Danasoft - <a href="http://www.danasoft.com">For Backgrounds and Layouts</a></p></div>
  Reply With Quote
Old 9th June 2005, 06:27 AM   #4
diyAudio Member
 
thomas997's Avatar
 
Join Date: Feb 2004
Location: Vancouver
Use the example PCB from the datasheet.

It works nicely if you have access to a laser printer, or some other DIY method. I just did it a couple weeks ago.

Only thing you have to worry about is connecting the top and bottom layers. I soldered all components on both sides of the board, and used copper wire where there is no component lead.

Im still working on a power supply and pre-amp for it, so I cant tell you the final result.

So far it works, little hiss noise from the speaker. I could drop the output cutoff to take care of that.
  Reply With Quote
Old 24th June 2005, 07:51 PM   #5
diyAudio Member
 
Join Date: Apr 2005
Location: In the Wild, Wild West
The gerber files and all the info you would need to have someone make boards for you is found here: http://www.national.com/appinfo/audi...19,968,00.html

These chips can be difficult to work so be warned. You might want to go to this page: http://www.national.com/appinfo/audio/ and try out the Class D Design Guide to see if what you want is even possible. The Overture Design guide will help you with that LM4780.

The LM46521/52 full range design is only really good for about 100W. If you have a very stiff power supply you might be able to run higher. The biggest weakness of the LM4651/52 chipset is that it only has an abs max of 44V (+/-22V).

-SL
  Reply With Quote
Old 25th June 2005, 01:11 AM   #6
Jorge is offline Jorge  Brazil
diyAudio Member
 
Join Date: Apr 2001
Location: Brazil
Have you considered some of the Tripath based 41Hz Audio kits?

http://www.41hz.com/
  Reply With Quote
Old 10th August 2005, 07:39 AM   #7
diyAudio Member
 
Join Date: Jan 2005
Location: hk
Default pcb for LM4651 and LM4652

I have made some boards from the Gebber files from National semi condutor from PCB company. I may be able to offer one or two boards. It is professional quality and of 2 oz copper.
  Reply With Quote
Old 24th August 2005, 03:45 PM   #8
crissty is offline crissty  Greenland
diyAudio Member
 
Join Date: May 2005
Location: Greenland
Can somebody post PCB layout for 2 Paralleled LM4652 for 250W subwoofer application
  Reply With Quote
Old 24th August 2005, 03:51 PM   #9
Account Disabled
 
Join Date: Feb 2004
Send a message via AIM to classd4sure Send a message via MSN to classd4sure
I think you want the DIFM (Do It For Me) website
  Reply With Quote
Old 24th August 2005, 03:58 PM   #10
crissty is offline crissty  Greenland
diyAudio Member
 
Join Date: May 2005
Location: Greenland
Please dont get wild,

In class D Amps PCB Design is very critical, A novice as me will not be able to do that, and i wanted to know if anybody has tried & tested with 2 paralled LM4652 for increased output.
  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
LM4651/LM4652 replacement rtarbell Class D 5 15th May 2006 01:40 AM
Lm4651, Lm4652 spudspud Chip Amps 20 29th March 2005 12:41 PM
lm4651/2 power supply amps abreo27 Solid State 0 13th July 2004 05:00 PM
PCB for LM4651/LM4652 soundNERD Chip Amps 4 29th May 2004 06:54 PM
LM4651/ LM4652 power supply audioaction Chip Amps 0 17th October 2003 02:55 AM


New To Site? Need Help?

All times are GMT. The time now is 02:34 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