new LM4780 layout, any comments? - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

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 23rd January 2009, 05:45 AM   #1
BrianGT is offline BrianGT  United States
diyAudio Moderator Emeritus
 
BrianGT's Avatar
 
Join Date: Jan 2002
Location: near Atlanta, GA
Send a message via AIM to BrianGT
Default new LM4780 layout, any comments?

I haven't built up a LM4780 amp for a while, so I decided to make a new layout.

Goals for layout:
- single LM4780 + PSU on a single board
- able to be used in stereo or parallel
- reasonably compact: 3" x 5.5"
- decently robust power supply
- attempt at decent separation of grounds, allowing for a star ground for the inputs, going back to the main ground, a separate ground return for the output zobel networks and also the output grounds tied back close to the main ground.

What do you guys think?
Attached Images
File Type: gif 4780-pcb.gif (46.6 KB, 2254 views)
  Reply With Quote
Old 23rd January 2009, 05:46 AM   #2
BrianGT is offline BrianGT  United States
diyAudio Moderator Emeritus
 
BrianGT's Avatar
 
Join Date: Jan 2002
Location: near Atlanta, GA
Send a message via AIM to BrianGT
schematic
Attached Files
File Type: pdf 4780-sch.pdf (17.3 KB, 608 views)
  Reply With Quote
Old 23rd January 2009, 05:53 AM   #3
BrianGT is offline BrianGT  United States
diyAudio Moderator Emeritus
 
BrianGT's Avatar
 
Join Date: Jan 2002
Location: near Atlanta, GA
Send a message via AIM to BrianGT
Here is the bottom layer shown on top of the top layer, with the bottom silk screen (OGND is shown in the wrong place currently)

Green = bottom layer
Red = top layer
Attached Images
File Type: gif 4780-pcb-bottom.gif (32.0 KB, 1946 views)
  Reply With Quote
Old 23rd January 2009, 05:20 PM   #4
ratza is offline ratza  Romania
diyAudio Member
 
ratza's Avatar
 
Join Date: Dec 2007
Location: Sibiu, Romania
Excellent. I don't think you can shorten tracks more than they are.
__________________
Any solution is a compromise.
  Reply With Quote
Old 23rd January 2009, 09:24 PM   #5
BrianGT is offline BrianGT  United States
diyAudio Moderator Emeritus
 
BrianGT's Avatar
 
Join Date: Jan 2002
Location: near Atlanta, GA
Send a message via AIM to BrianGT
My only major concern is leaving enough clearance to attach the chip to the heatsink. I believe that with the large caps pushed back, an angled screwdriver should be able to screw the board into the heatsink.

--
Brian
  Reply With Quote
Old 23rd January 2009, 09:29 PM   #6
diyAudio Member
 
Join Date: Sep 2005
Default Re: new LM4780 layout, any comments?

Quote:
Originally posted by BrianGT
attempt at decent separation of grounds

Great!

Any interest in going back and doing the same for other chips? 3886?

Also, why not make it so that the board could be cut if someone wished to do so?
  Reply With Quote
Old 23rd January 2009, 10:51 PM   #7
BrianGT is offline BrianGT  United States
diyAudio Moderator Emeritus
 
BrianGT's Avatar
 
Join Date: Jan 2002
Location: near Atlanta, GA
Send a message via AIM to BrianGT
Default Re: Re: new LM4780 layout, any comments?

Quote:
Originally posted by toolsresearch



Great!

Any interest in going back and doing the same for other chips? 3886?

Also, why not make it so that the board could be cut if someone wished to do so?
Here is a similar layout that I made for the LM3886, which I haven't finished fully yet.

The idea here is to have a narrow board, so that you can easily pop 2 aside each other for a dual mono amp and avoid having to wire up the power supply board to the amp board. (or to the same effect a 5 channel amp).

-Brian
Attached Images
File Type: gif 3886mono.gif (32.6 KB, 1824 views)
  Reply With Quote
Old 24th January 2009, 10:20 AM   #8
ratza is offline ratza  Romania
diyAudio Member
 
ratza's Avatar
 
Join Date: Dec 2007
Location: Sibiu, Romania
Quote:
Originally posted by BrianGT
My only major concern is leaving enough clearance to attach the chip to the heatsink. I believe that with the large caps pushed back, an angled screwdriver should be able to screw the board into the heatsink.

--
Brian

On my amplifiers I placed the screws behind the heatsink and the nut + washer on the chip or transistors, so this might be an option.
__________________
Any solution is a compromise.
  Reply With Quote
Old 24th January 2009, 06:58 PM   #9
diyAudio Member
 
raypalmer's Avatar
 
Join Date: Dec 2008
Location: Burlington
I love them! I hope it's ready by the time I start my monoblok project.
__________________
Wherever you go there you are.
  Reply With Quote
Old 24th January 2009, 07:44 PM   #10
Ted205 is offline Ted205  United Kingdom
diyAudio Member
 
Ted205's Avatar
 
Join Date: Jun 2008
would be a shame to have the psu connected as the only option.
  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
Crossover Layout Comments luvdunhill Multi-Way 13 4th February 2009 02:50 PM
Need comments on this P3A PCB layout goering Solid State 7 27th August 2004 06:04 AM
My new Aleph layout. Comments? louischia Pass Labs 12 18th May 2003 08:02 PM


New To Site? Need Help?

All times are GMT. The time now is 03:36 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