Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

fixed tovariable power suply
fixed tovariable power suply
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
Thread Tools Search this Thread
Old 30th November 2006, 11:52 AM   #1
salil_kamat2 is offline salil_kamat2  India
diyAudio Member
Join Date: Nov 2006
Default fixed tovariable power suply

I am a first year ELECTRONICS postgraduate student from Mumbai,INDIA. I want to know whether we can convert--dual power supply i.e. the one built using LM7805(positive voltage regulator) and LM7905(negative voltage regulator) to make a variable supply which uses LM317 (adjustable voltage regulator) ????

Basically, can we find such a circuit which establishes a relation between the two?

Hope that you will definitely help me out at your very earliest!

PLEASE HELP ME !!!!!!!!!!!!!!!!!!!
  Reply With Quote
Old 30th November 2006, 12:45 PM   #2
richie00boy is offline richie00boy  United Kingdom
Did it Himself
diyAudio Member
richie00boy's Avatar
Join Date: Nov 2003
Location: Gloucestershire, England, UK
fixed tovariable power suply
You can use the transformer and rectifier, caps etc. The max output from the unit will probably be about the same as with the fixed regulators though. Also a new board will need to be made as the pinouts are different.
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, modules and more.
  Reply With Quote
Old 8th December 2006, 01:07 PM   #3
paulb is offline paulb  Canada
diyAudio Member
Join Date: Jun 2001
Location: Calgary
The 7905 would be replaced by an LM337 (adjustable negative regulator).
  Reply With Quote
Old 8th December 2006, 01:41 PM   #4
jackinnj is online now jackinnj  United States
diyAudio Member
jackinnj's Avatar
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
fixed tovariable power suply
if you want to establish the relationship between the two, go onto National Semi's website and search under "tracking regulator" -- it's a bit more complicated than just plugging in an LM337 for an LM3905 -- but you can control the output voltage with only one potentiometer thusly:
Attached Images
File Type: gif track.gif (14.1 KB, 53 views)
  Reply With Quote


fixed tovariable power suplyHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Power suply reduction leander Solid State 2 9th September 2005 07:54 AM
variable power suply csl113 Power Supplies 7 5th February 2005 02:19 PM
power suply help needed !!!!!!! mircea Chip Amps 0 28th June 2004 03:33 PM
Aleph5 caps for power suply cducati Pass Labs 2 20th February 2003 09:16 PM
LM3886 power suply... JoeBob Solid State 31 7th January 2002 01:36 AM

New To Site? Need Help?

All times are GMT. The time now is 03:48 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio