Help on LM3886 PCB Routing - Page 9 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 28th September 2012, 10:38 AM   #81
diyAudio Member
 
sachu888's Avatar
 
Join Date: Jul 2010
Location: India
Default PCB

Hi,
I am going to order few PCbs for this amp.Please let me know if anyone wants a PCB.


Regards,
Sachin
  Reply With Quote
Old 28th September 2012, 04:42 PM   #82
diyAudio Member
 
Join Date: Apr 2007
Well guys, i just tested the boards on a stereo setup and work like charm, rly quiet and no distortion or hummmm sound.

Ty guys for help me to make this pcb.

Cheers
  Reply With Quote
Old 28th September 2012, 06:14 PM   #83
diyAudio Member
 
Join Date: Oct 2007
necrofago, hope you noticed that your latest files had an error - the polarity of C1 was
wrong. I fixed it and make some minor cosmetic improvements.
Attached Images
File Type: png lm3886-fix.png (34.0 KB, 353 views)
File Type: png lm3886-fix-sch.png (12.6 KB, 350 views)
Attached Files
File Type: zip lm3886-fix.zip (66.9 KB, 82 views)
  Reply With Quote
Old 28th September 2012, 07:19 PM   #84
diyAudio Member
 
Join Date: Apr 2007
Ty quadtech i didint saw it, i just build the amp from memory. Ty for the advice.
  Reply With Quote
Old 6th October 2012, 06:51 PM   #85
vilts is offline vilts  Estonia
diyAudio Member
 
Join Date: Jan 2005
Location: Estonia
Send a message via Skype™ to vilts
I downloaded the Eagle files from quadtech post #83, but for some reason I can't see the ground plane. Any ideas of what I might be doing wrong in Eagle?
Attached Images
File Type: gif lm3886.gif (28.0 KB, 291 views)
__________________
A Thing Of Beauty is A Joy For Ever (J. Keats)
--- Knives and Engraving ---
  Reply With Quote
Old 6th October 2012, 07:29 PM   #86
KSTR is offline KSTR  Germany
diyAudio Member
 
KSTR's Avatar
 
Join Date: Jul 2007
Location: Central Berlin, Germany
Use the "ratsnest" button, or simply type "r" (then return) in Eagle's command line.

You can specify if ratsnest processes polygons or not :
"set poly on"
"set poly off"
in the commandline, again (and without ")

Once a polygon have been rendered, there is no easy way to turn it off again, but there are workarounds :
a) drag one edge a bit away, then back again, then refresh display (zoom out, etc).
c) close the .BRD only and the open it again from the schematic editor. DO save changes if prompted so, otherwise board and schematic will be inconsistent and will stop being updated synchronuously (the so-called back-annotation).
  Reply With Quote
Old 8th October 2012, 08:40 PM   #87
vilts is offline vilts  Estonia
diyAudio Member
 
Join Date: Jan 2005
Location: Estonia
Send a message via Skype™ to vilts
Thanks, 'ratsnest' command did the trick.
__________________
A Thing Of Beauty is A Joy For Ever (J. Keats)
--- Knives and Engraving ---
  Reply With Quote
Old 26th September 2015, 06:52 PM   #88
diyAudio Member
 
Join Date: Sep 2015
Sorry to revive a dead thread but the title is just fitting and I used one of the layouts posted here as reference.

I took the necrofago's layout (the one edited by quadtech) and tried my little best to modify it into a version without SMDs.

This is the result - any comments?
Attached Images
File Type: png LM3886.png (41.0 KB, 145 views)
File Type: png LM3886_S.png (32.6 KB, 143 views)
  Reply With Quote
Old 27th September 2015, 09:26 AM   #89
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
R3 is too far away from R1 and R2. = too big a loop area in the input wiring.
The trace from input terminal pin2 to C1 should be UNDER C1 to minimise loop area.
Can you locate c5,6,10& 11 much closer to power pins. At least one cap at each power pin.
I don't know what type of current pulses flow into pin5, but hardly anyone adds HF decoupling to this pin
Why does it get ignored?
Do they know something about the pin5 current flow that I have not seen reported?
I don't like C2 tied into pin9.
Read about stability and decide whether a Pin9 capacitor will help or hinder stability.
Instead I tie C2 to Signal Return alongside R2.
C3 and Cz are too low value.

Redraw your sch input with real traces joining all the Signal Grounds, move C3 to tie into the bottom of R2. Then your input looks more like what it is, a differential input stage.
__________________
regards Andrew T.
Sent from my desktop computer using a keyboard

Last edited by AndrewT; 27th September 2015 at 09:29 AM.
  Reply With Quote
Old 16th November 2015, 11:43 AM   #90
diyAudio Member
 
Join Date: Dec 2012
Location: Malaysia
Hi all.

How do you connect the power ground to signal input ground? 1ohm resistor?

Thanks
  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
PCB routing for audioamps SM2GXN Solid State 38 4th May 2012 04:28 AM
PCB placing and routing akis Parts 9 7th January 2012 08:48 AM
Any tips for routing heaters on a PCB KX36 Tubes / Valves 10 14th August 2011 02:26 AM
PCB Routing Mark245 Parts 15 27th May 2009 07:54 PM


New To Site? Need Help?

All times are GMT. The time now is 10:55 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright ©1999-2016 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki