Regulated power supply - 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 23rd August 2005, 07:46 AM   #1
crissty is offline crissty  Greenland
diyAudio Member
 
Join Date: May 2005
Location: Greenland
Default Regulated power supply

I have made and tested chip amp from 3886 by National Semi, and tested it with 20V-0-20V 100Va transformer.

Actually now i got a transformer rated @35V-0-35V rail, but after bridge i get 50V DC rails.

How can i use a regulator for getting 35v. I dont wanna go in for linear regulator design as it will have quite high losses & heat dissipation.

I need a schematic design of SMPS, using 3525/3524 and mosfets, to get regulated +-35V 4-5Amps
  Reply With Quote
Old 23rd August 2005, 09:10 PM   #2
mateo88 is offline mateo88  United States
diyAudio Member
 
Join Date: May 2004
Location: Argyle, Texas
An lm338 or lt1084 are surprisingly efficient and don't require a big heatsink, either. I would reccomend giving one of those a shot, since the circuit will be very simple and very cheap (and very good, too!).
  Reply With Quote
Old 23rd August 2005, 09:19 PM   #3
diyAudio Member
 
Join Date: Apr 2003
Location: New York
I think the LM338 can get hot. I have them
regulating 38V down to 29V. I've attached
them to a 2" heatsink. You can touch the
heatsink but not too long.

Harry
  Reply With Quote
Old 23rd August 2005, 10:18 PM   #4
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
Quote:
Originally posted by h_andree
I think the LM338 can get hot. I have them
regulating 38V down to 29V. I've attached
them to a 2" heatsink. You can touch the
heatsink but not too long.
If you can't keep your hand on the heatsink then you need more heatsink or a fan.

A hand's touch is usually a good judge when a part is being stressed by heat.

If you don't pay attention to that, the part may have quite a short life.


Carlos
  Reply With Quote
Old 24th August 2005, 02:08 AM   #5
mateo88 is offline mateo88  United States
diyAudio Member
 
Join Date: May 2004
Location: Argyle, Texas
Hmmm, that's odd. My lm338's don't get hot at all, and really are barely even warm on 1.5" x 1/4" pieces of aluminum. They're regulating 35v to 26v.
  Reply With Quote
Old 24th August 2005, 04:57 AM   #6
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
Quote:
Originally posted by mateo88
An lm338 or lt1084 are surprisingly efficient and don't require a big heatsink, either. I would reccomend giving one of those a shot, since the circuit will be very simple and very cheap (and very good, too!).
This type of regulator is UNEFFECIENT by nature and can go down to almost 0% effeciency. How much heat you must burn away has to do with the load and how much voltage drop you have.
__________________
/Per-Anders (my first name) or P-A as my friends call me
Super Regulator SSR03 Group buy. Still time for signing up.
  Reply With Quote
Old 24th August 2005, 02:17 PM   #7
crissty is offline crissty  Greenland
diyAudio Member
 
Join Date: May 2005
Location: Greenland
Please..... I need schem for SMPS type.
  Reply With Quote
Old 24th August 2005, 03:14 PM   #8
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally posted by carlmart


If you can't keep your hand on the heatsink then you need more heatsink or a fan.

A hand's touch is usually a good judge when a part is being stressed by heat.

If you don't pay attention to that, the part may have quite a short life.


Carlos

Calos,

I you can touch it but not hold it, it is probably close to 50 degrees Celcius. Nothing to worry about!

Jan Didden
__________________
If you don't change your beliefs, your life will be like this forever. Is that good news? - W. S. Maugham
Check out Linear Audio!
  Reply With Quote
Old 24th August 2005, 03:16 PM   #9
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally posted by peranders

This type of regulator is UNEFFECIENT by nature and can go down to almost 0% effeciency. How much heat you must burn away has to do with the load and how much voltage drop you have.

Corretc. The dissipation in Watts depends on the product of voltage the regulator has to drop times the current it is passing. Different implementations have different dissipation requirements. One man's cool chip can become another man's burning hell

Jan Didden
__________________
If you don't change your beliefs, your life will be like this forever. Is that good news? - W. S. Maugham
Check out Linear Audio!
  Reply With Quote
Old 24th August 2005, 06:46 PM   #10
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
Quote:
Originally posted by janneman

I you can touch it but not hold it, it is probably close to 50 degrees Celcius. Nothing to worry about!

You are certainly right. I am probably exaggerating in my heat concern on electronic parts.

Some say a bit of temperature is good for the sound.

Bottom line: it's important to see if the heatsink metal close to the part is about the same temperature as the part itself, to see if the heat transfer is being properly done.


Carlos
  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
Regulated power supply meanman1964 Everything Else 13 9th April 2007 02:50 AM
Regulated DC power supply Panicos K Power Supplies 11 21st October 2006 12:32 AM
regulated power supply yugaaa Solid State 17 28th January 2003 02:39 PM
Using regulated power supply for A3 kirc Pass Labs 4 25th October 2002 12:09 PM
regulated power supply yugaaa Solid State 3 17th June 2002 06:22 PM


New To Site? Need Help?

All times are GMT. The time now is 10:59 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