Buildind switched power supply for amp - 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 27th November 2003, 02:49 PM   #1
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Default Buildind switched power supply for amp

I need to build a power supply that can power 2 LM3886 at full power, no matter in normal mode, or bridged mode. I just can't afford that large of a transformer, so thought about designing a switching power supply. I have never worked off the ac line before, so that worries me a bit, but I am sure it would be fine. I have a old Dell PS from a computer, which after tearing it apart thinking it was broken, I found the fuse. So I should be able to get parts for it. Can anybody help me design this? I need 48VCT @ about 10A.

Thanks, Mike
  Reply With Quote
Old 27th November 2003, 03:41 PM   #2
diyAudio Member
 
Join Date: May 2003
Location: USA
I had the same idea a while back you might want to check out this link.

http://diyaudio.com/forums/showthrea...055&highlight=
  Reply With Quote
Old 27th November 2003, 07:38 PM   #3
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
I didn't exactly mean that. I meant that i have a source of parts to do this, and want to build my own
  Reply With Quote
Old 27th November 2003, 08:34 PM   #4
diyAudio Member
 
Hi Speed's Avatar
 
Join Date: Sep 2002
Location: PR
Hi all

Find in this post

http://diyaudio.com/forums/showthrea...threadid=21110

http://diyaudio.com/forums/showthrea...threadid=22352
__________________
Hi Speed
Thanks
  Reply With Quote
Old 28th November 2003, 01:58 AM   #5
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Hi speed,

The posts you sent me to was about 12VDC operated switching supplies.

My application is in a subwoofer, so I need 120VAC operation.

The following is a list of parts I tore out of the PC supply, exactly what the chips say:

1. ST 9448
Malaysia
P3N90

2. CTB34D
-|>|--|<|- (two diodes)
40 28

3. C92W
-|>|--|<|- (two diodes)
82

4. 37-C5151103
9422C

5. 42-M52211P02 HP OK
LITEON 9452 JC

6. 42-M51511P03 HP OK
LITEON 9504 JC

7 and 8. L7905CV
W991J9427
MALAYSIA
ST

9. LT KBJ406G

10. a coil wound around a metal circle with 12 pins
labeled 37-C5151102
9422C
and on the plastic bottom, BASE-07-1

Hopefully these parts are useful, and hopefully i didn't just waste 5 minutes entering them in.

1-3 are transistors
4-6 are transformers
7-8 are transistors (possibly 7805 regulators?)
9 is a bridge rectifier

Thanks for the help
  Reply With Quote
Old 28th November 2003, 02:13 AM   #6
Banned
 
Join Date: Nov 2002
Location: Adelaide, Australia
Send a message via MSN to SkinnyBoy
just go and buy a transformer.....

I dunno where from....

I can get an 18volt CT 250VA transformer for $25 from a surplus place.... use a voltage multiplier thingo, and you have +-25 volt rails and enough current to run the amps to their fullest output..

don't even consider switchmode...
  Reply With Quote
Old 28th November 2003, 02:32 AM   #7
diyAudio Member
 
li_gangyi's Avatar
 
Join Date: Jun 2003
Location: Woodlands Circle
yeah...I'll bet after u built the SMPSU and got it to work...it will exceed the price of a full trafo with caps...plus the SMPSU will give a lot of interference due to the switching involved...wouldn't really recommend it...but if you wanna do it for fun...by all means go ahead...I've seen some SMPSUs (they are not for PCs) that have a +/-24V output after tweaking...check out this site here for a bit of info (though he used them for a Laser supply) I think it's pretty cool.
http://www.electricstuff.co.uk/argonlaser.html
__________________
Kids in the back seat cause accidents...Accidents in the back seat cause kids...
  Reply With Quote
Old 28th November 2003, 03:31 AM   #8
diyAudio Member
 
uvodee's Avatar
 
Join Date: Aug 2002
Location: Washington
Default don't forget

to consult www.mpja.com

sometimes interesting deals.... but you need to be fast, they are always running out of stuff faster than you can think

besides apexjr.com ...

J-P
  Reply With Quote
Old 28th November 2003, 03:39 AM   #9
diyAudio Member
 
uvodee's Avatar
 
Join Date: Aug 2002
Location: Washington
Default I bought a

Toroid 44 - 0 - 44 volt 8 A

first thought it would be too much but the specs from nat semi told me it would be OK , the DC is about 62 volts
The amp never runs out of power


I bought 3 of them at All Electronics, they were dirt cheap and had been removed from existing merchandise. At $22 a piece they are really a good deal.

I was wondering if your solution could be connecting 2 transfo's to jack up the voltage upto a descent #
like
12 v / 0 + 12 v / 0 v
in this case ou would get 24 volts ....... just be sure you have enough A.
  Reply With Quote
Old 28th November 2003, 03:45 AM   #10
Banned
 
Join Date: Nov 2002
Location: Adelaide, Australia
Send a message via MSN to SkinnyBoy
umm.. thats WAY too high.. :S

Max I would ever even CONSIDER using would be +-48 volts...
  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
Switched Power Supply Design Course gala Power Supplies 1 21st January 2006 10:19 AM
PFC Switched-Mode Power Supply N-Channel Power Supplies 57 13th June 2005 07:56 PM
Switched mode power supply MMicke Car Audio 3 19th February 2005 10:42 AM
Switched power supply? Johan_Ch Tubes / Valves 38 31st January 2004 11:53 AM
Switched Mode vs Linear Power Supply royalmp2001 Solid State 4 12th July 2002 08:04 PM


New To Site? Need Help?

All times are GMT. The time now is 03:31 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