Amplifier PCB Layout Guidelines? - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

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 18th December 2005, 01:19 AM   #1
diyAudio Member
 
ron.eddy's Avatar
 
Join Date: Nov 2005
Location: Iron Range - Minnesota, USA
Send a message via ICQ to ron.eddy Send a message via MSN to ron.eddy
Question Amplifier PCB Layout Guidelines?

I was attempting to make a few circuit boards in Eagle the other day and after spending hours and hours trying to make the components fit while keeping signals in order I gave up. I did eventually make a "complete" layout for the circuit I was working on (See pics below) but I am not sure it is a good way to go. It is just a simple circuit for a Randy Slone headphone amp and I just wanted to practice laying out components using it. But I just am not happy with it at all. It seems like it got put together only through luck, and not skill at all!

So my question is: Are there any general guidelines you pros could give a newbie like me in laying out a circuit, especially when it has multiple pin devices in it such as ICs or chip amp transistors like the LM3886? I mean, with what components should I start? What are some things to keep in mind as far as certain signals being next to certain components? Etc. From what I gather all this comes with experience, but I would like to speed that up a bit, since experience could take a while (I never was all that patient ).

Any tips would help a great deal, I just don't have a very creative brain as far as improvising things like layouts, so any kind of structure to this process will help me and any other like minded DIYer out there.

Thanks!

- Ron

Click the image to open in full size.

Click the image to open in full size.
  Reply With Quote
Old 18th December 2005, 01:25 AM   #2
Leolabs is offline Leolabs  Malaysia
diyAudio Member
 
Leolabs's Avatar
 
Join Date: Dec 2004
Location: Bukit Mertajam
Send a message via MSN to Leolabs
try to search on the forum,with the term"circuit board design".
  Reply With Quote
Old 18th December 2005, 01:40 AM   #3
diyAudio Member
 
ron.eddy's Avatar
 
Join Date: Nov 2005
Location: Iron Range - Minnesota, USA
Send a message via ICQ to ron.eddy Send a message via MSN to ron.eddy
Searching this forum didn't yield very many direct responses to this sort of question, but going into each project and reading the tips on those specific circuits does help. Thanks for the advice. I just wish there was a more centralized place to learn.

I should note that I have already read the PCB design guide here and am actually asking in this forum for any little tips or advice you all could give for audio specific circuits, as I said especially when IC's/multiple pin chips are involved.

Ron
  Reply With Quote
Old 18th December 2005, 01:44 AM   #4
poobah is offline poobah  United States
diyAudio Member
 
poobah's Avatar
 
Join Date: Nov 2005
Looks fine dude ... and it ain't easy... takes lot of practice to do it fast.

If Eagle lets you do 45's, replace all those 90 deg turns with 2 45's.

If you want it smaller... that just takes work and patience.

As far as the "black magic" is concerned. just keep your outputs away from your inputs... audio is pretty forgiving as far PCB's go.

  Reply With Quote
Old 18th December 2005, 01:47 AM   #5
poobah is offline poobah  United States
diyAudio Member
 
poobah's Avatar
 
Join Date: Nov 2005
Is this going to be a single or double sided board???? LOOKS like single...
  Reply With Quote
Old 18th December 2005, 02:12 AM   #6
diyAudio Member
 
ron.eddy's Avatar
 
Join Date: Nov 2005
Location: Iron Range - Minnesota, USA
Send a message via ICQ to ron.eddy Send a message via MSN to ron.eddy
Yes, it is a single side, however there is one component on the top side (the 1206 SMT capacitor) but that will actually be going on the bottom side, I just couldn't figure out how to make eagle put it down there so I just left it as is, figuring if I ever made the board I can make it go on the bottom, real close to the two pins it is connected to.

Anyway, what you say about audio circuits is exactly what I thought too (I figured at these low frequencies there shouldn't be anything to worry about) but I think some may disagree on this forum about the audio being pretty forgiving. In fact, this is what most of my confusion rises from. When I go to look at other's projects on this forum and they ask for advice on their PCB layout, usually they get a TON of responses telling them to keep signal A away from those caps, or make sure those traces are short or whatnot. So seeing all of that frustrates me, since I know there are so many suggestions out there and it isn't possible to remember them all.

In any case, I guess a good question I could ask is, how long does it take one of you more experienced DIYers to layout a simple circuit such as the one I have done? This one took me 14 hours and I just never could get into any sort of rhyme or rythm with it.
  Reply With Quote
Old 18th December 2005, 02:27 AM   #7
diyAudio Member
 
Join Date: Sep 2004
Location: Elk River MN
Practice, practice, practice.
  Reply With Quote
Old 18th December 2005, 02:28 AM   #8
poobah is offline poobah  United States
diyAudio Member
 
poobah's Avatar
 
Join Date: Nov 2005
Check you email -
  Reply With Quote
Old 18th December 2005, 02:37 AM   #9
mzzj is offline mzzj  Finland
diyAudio Member
 
Join Date: Jul 2005
Location: 65N 25E
Quote:
Originally posted by ron.eddy

Anyway, what you say about audio circuits is exactly what I thought too (I figured at these low frequencies there shouldn't be anything to worry about) but I think some may disagree on this forum about the audio being pretty forgiving.
It depends where you compare it.
Try fitting SMPS and a mic preamp on same board if you like challenges

Where you are going to connect those bypass cap gounds together? AD797 is usually tought as tricky nut to bypass compared to any other audio-opamp. Aim to keep total trace+component lenght minimal between supply pins, bypass caps and ground.

I usually start with bypass cap placement, then feedback resistors and after that rest of the stuff where it fits. Dont be shamed to use jump wires on 1-side board, its way more better to use couple of jumps than run signals around the board in loops trying to not use jumper wires. Some people seem to rate pcb layout by amount of jumpers used, thinking that less is better.
  Reply With Quote
Old 18th December 2005, 02:37 AM   #10
diyAudio Member
 
ron.eddy's Avatar
 
Join Date: Nov 2005
Location: Iron Range - Minnesota, USA
Send a message via ICQ to ron.eddy Send a message via MSN to ron.eddy
Quote:
Originally posted by Mike Gergen
Practice, practice, practice.
Yea, good plan. It is fun, in an odd sort of way.
  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
Amplifier Layout - Help & advice needed andrew_whitham Tubes / Valves 5 8th May 2007 08:49 PM
New amplifier project -my layout Curly Woods Tubes / Valves 7 11th January 2007 06:15 PM
swr amplifier schematics and pc board layout charonodaemon Parts 0 22nd July 2006 08:51 PM
SJS SE108Mk2 Amplifier layout. DVDHack Tubes / Valves 13 11th February 2004 07:44 AM


New To Site? Need Help?

All times are GMT. The time now is 05:38 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