Voltage Divider question - 6 from 12 Volts - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies

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 14th August 2009, 01:30 PM   #1
Brit01 is offline Brit01  United Kingdom
diyAudio Member
 
Join Date: Jul 2008
Default Voltage Divider question - 6 from 12 Volts

Guys,

Can I use a simple voltage divider circuit to get 6 Volts out of a 12 volt transformer?
I have a secondary 12V at 4 Amps.

What would be suitable resistor values (and wattage) here to get 6 Volts at 2.5 amps min. from 12 volts? I want to supply a 6080 heater.

I found this great calculator:

http://www.educalc.net/876080.page
  Reply With Quote
Old 14th August 2009, 02:34 PM   #2
poynton is offline poynton  United Kingdom
diyAudio Member
 
poynton's Avatar
 
Join Date: Mar 2005
Location: A life on the ocean waves when I'm not at home in N. Wales (but I'm not Welsh so no sheep jokes!)
Big Resistor needed !!!!

To drop 6V at 2.5A requires 6 / 2.5 = 2.4ohms at 15watt rating


Get a 6v transformer - less heat and probably cheaper


Andy
__________________
If it ain't broke, break it !! Then fix it again. It's called DIY !
  Reply With Quote
Old 14th August 2009, 02:43 PM   #3
wwenze is offline wwenze  Singapore
diyAudio Member
 
Join Date: Mar 2008
How about changing your circuit to two 6080s with the 12V feeding their heaters in series instead?
  Reply With Quote
Old 14th August 2009, 02:44 PM   #4
Brit01 is offline Brit01  United Kingdom
diyAudio Member
 
Join Date: Jul 2008
Thks Andy.

Thought it was going to take some heat.

Although I may be able to get some 20W resistors for about 2 USD here.

Iron is not cheap here. Let me find out.
  Reply With Quote
Old 14th August 2009, 02:46 PM   #5
Brit01 is offline Brit01  United Kingdom
diyAudio Member
 
Join Date: Jul 2008
Quote:
How about changing your circuit to two 6080s with the 12V feeding their heaters in series instead?
True. The other option I thought about.

If I've got 4 amps at 12V.

Then 2 x 2.5 amp heaters would be 5 amps.

But at 6 volts this would be ok yes?
  Reply With Quote
Old 14th August 2009, 03:37 PM   #6
diyAudio Member
 
Join Date: Nov 2008
Location: Brazil
with any value of resistor, you make a divisor EX 0.5 ohms + 0.5 ohms...
More the correct you use a Zener diode (1N5340)
  Reply With Quote
Old 14th August 2009, 03:41 PM   #7
Brit01 is offline Brit01  United Kingdom
diyAudio Member
 
Join Date: Jul 2008
Quote:
More the correct you use a Zener diode (1N5340)

sorry not sure what you mean.

A zener with each resistor? Or as a substitute to create the required resistance?
  Reply With Quote
Old 14th August 2009, 04:06 PM   #8
diyAudio Member
 
Join Date: Nov 2008
Location: Brazil
Quote:
Originally posted by Brit01



sorry not sure what you mean.

A zener with each resistor? Or as a substitute to create the required resistance?
You need not resitores, only one Zener diode, above 6 v leads, so does the voltage not exceed 6 v, look fig.
-his source is not symmetric, will need only one Zener diode....
Attached Images
File Type: gif regulated.gif (17.2 KB, 114 views)
  Reply With Quote
Old 14th August 2009, 04:14 PM   #9
pjp is offline pjp  India
diyAudio Member
 
pjp's Avatar
 
Join Date: Nov 2006
Location: under the rainclouds
Rafael.luc I hope you know what you're talking about... 1N5340 is a 5W part which can pass approx. 800mA ...
  Reply With Quote
Old 14th August 2009, 04:22 PM   #10
Brit01 is offline Brit01  United Kingdom
diyAudio Member
 
Join Date: Jul 2008
Quote:
1N5340 is a 5W part which can pass approx. 800mA .
yep. I need something they will be capable of handling 5 amps at least.
  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



New To Site? Need Help?

All times are GMT. The time now is 09:55 AM.


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