My First LM3886 GC - 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 1st June 2008, 12:53 AM   #1
diyAudio Member
 
Join Date: Aug 2004
Location: Argentina
Default My First LM3886 GC

Hi guys, im using the Schematic that i found in the Datasheet of the LM3886, its how i draw it

http://www.proyectosdiy.com/_tmp/sch.pdf

and i draw the PCB using just one side in that way

http://www.proyectosdiy.com/_tmp/pcb.pdf


can someone please tellme some tips about the Sch and PCB?

i dont know if can add something to the schematic to get it sound better.

or if can fix something in the PCB, im now on this

Thanks in advance
  Reply With Quote
Old 1st June 2008, 01:31 AM   #2
diyAudio Member
 
Dino-Indo's Avatar
 
Join Date: Jan 2007
Hi Samsagaz,

May I propose the attached PCB Layout..
I didn't built it myself... purchased local from an Indonesian supplier here.. but probably you could try to implement it...

It sounded really good... I'm using some Riken MetalFilm 0.5 Watt resistors and some Elna RE3 blue capacitors 1000 uF/50V (for power supply smoothing caps on C 9 and C 10).

And instead of placing 0.1uF MKM poly cap on C7 and C8 also installed additional Elna RE3 blue capacitors 1000 uF/50V on C7 and C 8 position and then putting the 0.1uF cap below of the PCB at the feet of these additional 1000uF caps...

Good Luck!!
Attached Images
File Type: jpg lm3886 pcb.jpg (61.3 KB, 1620 views)
  Reply With Quote
Old 1st June 2008, 03:34 AM   #3
sneih is offline sneih  Indonesia
diyAudio Member
 
sneih's Avatar
 
Join Date: May 2008
hi dino i'm confuses about caps position on C3 at your picture attached!

that's show polar like + - - +

is it right position?
  Reply With Quote
Old 1st June 2008, 04:35 AM   #4
diyAudio Member
 
Dino-Indo's Avatar
 
Join Date: Jan 2007
Yes.. you are right..
I installed them back to back.. so it's become non polar (?)
Hehehe..
But it does sound good...
  Reply With Quote
Old 1st June 2008, 04:46 AM   #5
sneih is offline sneih  Indonesia
diyAudio Member
 
sneih's Avatar
 
Join Date: May 2008
u mean: - + , -+ ?


thx!!
  Reply With Quote
Old 1st June 2008, 05:22 AM   #6
diyAudio Member
 
Dino-Indo's Avatar
 
Join Date: Jan 2007
Nope... just follow the silk screen/top face of the PCB (the green one).. So the lay out will be + - - +

Good luck!!
  Reply With Quote
Old 1st June 2008, 06:26 AM   #7
diyAudio Member
 
neutron7's Avatar
 
Join Date: Dec 2003
Location: Toronto Canada
If you dont need the extra few watts,

if you can still get them, the Lm3875 in my OPINION has a much smoother sound than the 3886
  Reply With Quote
Old 1st June 2008, 10:12 AM   #8
sneih is offline sneih  Indonesia
diyAudio Member
 
sneih's Avatar
 
Join Date: May 2008
Quote:
Originally posted by Dino-Indo
Nope... just follow the silk screen/top face of the PCB (the green one).. So the lay out will be + - - +

Good luck!!
thx
btw i also have this pcb n still in progress

my problem:
honestly i have 3-4 part that they included but not in pcb....
n i dont know how to install them
ex:
- C4: 47pF-50pF = that seems not in the pcb..

- C5,9,10: 100uF/50V = where i install this part? replace with 1000uf?

- R4, R6: ??
  Reply With Quote
Old 1st June 2008, 12:24 PM   #9
diyAudio Member
 
Join Date: Aug 2004
Location: Argentina
i will build LM3875 too, i wanna test diferents GC.

and want to build my own PCB in all the cases.

But i just dont know if the Datasheet schematic are the best choice, ir can be improved.

Regards
  Reply With Quote
Old 1st June 2008, 12:50 PM   #10
Puffin is offline Puffin  United Kingdom
diyAudio Member
 
Join Date: Feb 2006
Location: U.K
samsagaz. Build a simple gainclone first, get to know the pin layouts intimately. Then start to experiment with different resistor feedback values, cap values etc.

I have just spent the best part of 2 days trying to make my second bridged gainclone (first was with LM3886's, this time with LM3875's). No sound, then lots of noise, then no signal input, rebuilt the thing 5 times ! Just got it working and it sounds fantastic (of course) I can go and eat now !.
  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
Psu Lm3886 Mayday Chip Amps 29 29th April 2007 06:10 PM
Lm3886 Bpa Tombson Chip Amps 99 21st August 2006 12:04 PM
Are two separate lm3886 = 2*lm3886 in parallel or bridge mode rs1026 Chip Amps 11 21st October 2004 10:24 AM
6*lm3886 Bpa Tim__x Chip Amps 1 15th August 2004 04:45 AM


New To Site? Need Help?

All times are GMT. The time now is 05:22 PM.


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