SSLTech Power Supply

[Sender]

Real quick question.

My friend just needs to a phantom supply and I was going to use Keith's design. If I'm not mistaken, I can simply just negate the +/- 18 side and just run the 48V side, right?

 

[Svart]

yep.

 

[mnats]

You can leave out the isolating caps before the bridge too if you're never going to use the +/-18 side.

 

[SSLtech]

Yep. lose the caps and DON'T make the ±18V's ground connection: You're left with a simple 48V PSU with even improved ripple performance.

Keith

 

[Sender]

[quote author="SSLtech"]Yep. lose the caps and DON'T make the ±18V's ground connection: You're left with a simple 48V PSU with even improved ripple performance.

Keith[/quote]

Straight from the horses mouth, thanks Keith.

So like this, pardon my sloppy penmanship.....

 

[Sender]

sorry guys, I just would like for someone with a little more knowledge then me to check this so I don't blow up!!!

Can someone weigh in?

 

[shabtek]

looks like you got it...straight from keef's scheem
edit:not implying to have mo' knowlaedge tho

 

[SSLtech]

Won't blow up. SHould give about 48V.

For better noise performance, try 10µF to ground at the ref pin of the 317, and a diode back to the output.

-See the "48V noise issues" thread that I ran some time ago. -I made my supply MUCH quieter when I did that.

Keith

 

[Svart]

http://www.theopiumdenproductions.com/PSUschemo.pdf

dug that one out of the past!

Take the phantom power section from the rectifier on and you'll be good to go.

I never did test this design though, but it simulated very well..

 

[burdij]

On your pencil sketch you show a connection from the negative terminal of the bridge rectifier to the tranformer center tap. Don't connect this that way. Connect the negative terminal of the bridge only to ground (negative side of your filter caps).

 

[SSLtech]

Ah yes... didn't see that line continuing leftwards, burdij is right... do NOT connect the center tap, as I mentioned two posts ago I think...

Keith

 

[Sender]

Hey Guys,

Let me further explain, sorry.

I'm going to powering this off a 20-0-20 transformer that is powering a Aphex lunch box. So I made the changes that were talked about in the noisy phantom thread.

I'm leaving the isolation caps (100uf/100V) in, just like in the original. So I should be able to just build this circuit and tie it right off of the transformer, right?

 

[SSLtech]

Ah yes indeed.

Basically, if you are going ANYWHERE with the center tap (be that a ±18V SSLtech regulator, or an Aphex regulator) then you MUST use the 100µF/100V caps in place. You can go bigger in value if you want to pull more current.

Keef

 

[Sender]

[quote author="SSLtech"]Ah yes indeed.

Basically, if you are going ANYWHERE with the center tap (be that a ±18V SSLtech regulator, or an Aphex regulator) then you MUST use the 100µF/100V caps in place. You can go bigger in value if you want to pull more current.

Keef[/quote]

Cool, about how much current can the 100u handle?

Also, is the placement of the 100nf and that second diode correct? Zener or just a 1N4003.

Also, how do you get that cool little 'mu' symbol.

 

[CJ]

Can we afford a measly 0.1 uf on the output?
We could let the 317 become a cap, their good at that, hey, how fast is a reg compared to a cap?
Firszt correct answer gets a slap on the ******.

never mind, i see that the 100 nf goes to minus.
please stack filter caps vertically you guys.

 

[Svart]

Firszt correct answer gets a slap on the ******.

OMG CJ

you are cracking up!

 

[CJ]

I'm not on crack.
Or crank.
But it does start with a C.

Get the fizz out of the zero crossing yet?
try 10.3 pf on the emitter of Q3.
Works for me.