Single sided non inverting LM3886 PCB - Page 4 - 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 31st March 2009, 04:36 PM   #31
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Quote:
Originally posted by zinblade19
please refer to the PSU schematic too (attached here)
a centre tapped transformer must use a single bridge rectifier to create the dual polarity supply.

The dual rectifier version you have shown can only be attached to dual secondaries.

Look up National's datasheet for the Cs description.

your schematic shows 1n5F and 220pF as the RF attenuation filter after the 1k0 plus Rs from your source.
Let's assume Rs=100r.
the RF filter ~ 1k0+100r and 1n5F+220pF ~1.9us.

The normally recommended range for the RF filter at the front end of a power amp is 0.5us to 1.5us.

You need to reduce your capacitor values and check the Rs of your source.
__________________
regards Andrew T.
  Reply With Quote
Old 31st March 2009, 04:51 PM   #32
diyAudio Member
 
Join Date: May 2008
Quote:
Originally posted by zinblade19
Sorry,didn't get it........once again please.
http://www.sengpielaudio.com/calculator-RCpad.htm
__________________
If you've always done it like that, then it's probably wrong. (Henry Ford)
  Reply With Quote
Old 31st March 2009, 04:56 PM   #33
diyAudio Member
 
Join Date: Mar 2009
Hi AndrewT,
thanks for your reply.
I would be using a centre-tapped transformer,
& a single bridge rectifier..........
I just wanted to show u the filter ckt of the rectifier..

I would be using EI transformers, any major disadvantages??
(didn't see anyone using it here)

  Reply With Quote
Old 31st March 2009, 05:04 PM   #34
diyAudio Member
 
ollebolle's Avatar
 
Join Date: Feb 2008
Location: Linkoping
If you compare a 200VA toroid with a 200VA EI you will notice the toroid is smaller!
I have read that toroid's are more efficient to. Lower losses.
  Reply With Quote
Old 31st March 2009, 05:10 PM   #35
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
toroids are generally more efficient. The result is that they run cooler.
Toroids are generally lower regulation. The result is that the voltage sags less under load.
Toroids offer size and weight advantages to manufacturers of amplifiers that do not apply to us DIYers.
Toroids pass more high frequency artifacts. This results in more noise getting through the PSU to the circuit beyond.

A high quality EI designed for good regulation and low magnetic fields will perform very well, but it will weigh far more and cost far more than an equivalent high quality toroid.
__________________
regards Andrew T.
  Reply With Quote
Old 1st April 2009, 07:16 AM   #36
diyAudio Member
 
Join Date: Mar 2009
Quote:
Originally posted by AndrewT
Hi,

Mute and GND should not share a trace with Signal Ground and NFB lower leg.
(in post #29)
Hi Andrew!
in the PCB layout Mute & gnd does not share a trace with signal gnd or NFB lower leg.

Anyway, can you tell me -- what would be the result with it???
  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
lm3886 single sided pcb ryan750 Chip Amps 55 9th July 2014 06:49 PM
My tiny single sided LM3886 PCB layout. :) Russ White Chip Amps 74 14th September 2008 06:53 PM
pa100 pcb single sided layout lm3886 dgaxeman Chip Amps 6 24th May 2006 01:45 AM


New To Site? Need Help?

All times are GMT. The time now is 09:45 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