Switching power supply? YEAH!

Started by Zero the hero, June 14, 2007, 06:26:10 PM

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Zero the hero

I uploaded a new page about my new power supply.
Everyone seems to be scared from switching unit because of noise and ripple, but I decided to test by myself how useless could be those units and it happened to become my primary power supply for gigging...
I had a laptop 19V 4.95A supply unit and I built a small circuit for correctly driving up-to ten SMD 7809 voltage regulators (yes, I filled all the pads with 10 regulators). Each channel is filtered and separated from each other.

It has been successfully tested with 6 pedals at the same time and two different amps, with no problem, noise or whatsoever, even with high-gain pedals.
Any impression?
Here's the link... (copy paste into a new window)
http://topopiccione.atspace.com/PJ25TPCMedusa.html

chunks717

I was thinking about doing this......glad it worked out.........

widdly

Do the regulators get very hot?  Regulating down from 19v to 9v, I would have though they would be cooking.

Zero the hero

Quote from: widdly on June 14, 2007, 09:49:12 PM
Do the regulators get very hot?  Regulating down from 19v to 9v, I would have though they would be cooking.

It was something I was afraid of too, but apparently with such small loads this is not really an issue: after 2 hours of playing, the enclosure (which acts like an heatsink) was still cold.

soulsonic

Nice job! This proves a theory that I was working up that switching supplies could work well if given the proper regulation. This is good news!

I think the reason switchers have gotten a bad reputation is because most of the ones being sold for fx pedals nowadays are cheap off-the-shelf generic units made for powering things like cell phone chargers or clocks or laptops or whatever and aren't designed properly for low noise. In fact, there's loads of poorly designed, cheap switchers out on the market. Desktop computer supplies are an excellent example; nowadays I see these things burn up all the time, but several years ago, I almost never saw them burn up. Switchers are a simple solution for some complex problems, but designers don't seem to be taking into account how crucial the design has to be for it to work reliably.

I'm going to try this myself - I've been trying to get together a design for a very small supply that can be hidden easily, but linear supplies are just too bulky. Now it seems a switcher can be a good option to try.
Check out my NEW DIY site - http://solgrind.wordpress.com

widdly

Sticking a rectifier on the layout might be handy idea too.  Then you could use just about any supply >= 12v.