diyAudio (
-   Power Supplies (
-   -   +/- dc power supply (

NeilParbrook 2nd February 2013 09:16 AM

+/- dc power supply
Hi there

I am wanting to build a new psu for 2 class d amps that I have to get rid of the bricks that I am currently using.

I have seen on eBay and other sites a number of circuits for this purpose that would allow me to mask use of some toroidal transformers I have from older projects.

My questions are as follows...

Can I plug one amp into the +dc and the other into the - dc?

How can I get only + dc out of one of these boards?

Is there a better option?

Look forward to hearing from you.


sofaspud 2nd February 2013 11:12 AM

You'll need to provide more information to get the help you seek. What are the outputs of the bricks you're using, and what are the transformers you have?

Can I plug one amp into the +dc and the other into the - dc?
Probably not a good idea.

NeilParbrook 2nd February 2013 01:58 PM

The amps are able to take between 10 and 30 volts dc.
The bricks are 12v 5amp Dc.

I have two toroidal transformers available one at 18volts and one at 24volts off the secondaries.

NeilParbrook 2nd February 2013 03:24 PM

So, please correct me if I am wrong...

I parallel up the secondary's to give me a higher current output

Run it through a rectifier to give me dc voltage.

Stick a nice fat smoothing cap across the dc and that's about it.

Is that right?

sofaspud 2nd February 2013 05:50 PM

That's basically it.
You need to keep in mind things like phase when paralleling secondaries, and peak voltage and ripple voltage when smoothing the dc.

NeilParbrook 2nd February 2013 06:09 PM

Great thanks sofaspud.

Ill keep an eye on the phases but the data sheet has that in.

I have 4 rubicon 10000uF 50v caps kicking around. Do you think they'll do for smoothing?

sofaspud 2nd February 2013 06:21 PM

Yes. But be aware that the 24V transformer will likely be over 30V after rectification and smoothing.

NeilParbrook 2nd February 2013 06:23 PM

That's great, I'll run with the 18volt transformer to be on the safe side.

Thanks for you help.

NeilParbrook 2nd February 2013 07:00 PM

1 Attachment(s)
Like This?

sofaspud 2nd February 2013 07:19 PM

Yes. Not sure you need 0.04F for your supply. Am sure you need a fuse on the unshown primary.

All times are GMT. The time now is 02:45 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio