Power supplies: What are you using?

[Adam Preble]

One area I've had trouble in has been the power supply. Coming from a
software background, I've been doing a lot of "copy/paste" and
experimentation in trying to put the power supply together. My design
basically uses the PinMame-HW "43Volt" design (http://www.pinmame-
hw.com/ -- site seems to be down at the moment), which is basically a
full wave rectifier. It uses a 30V toroidal transformer (Mouser
#546-182P15), bridge rectifier, and a 10,000 uf cap (for filtering/
smoothing the DC? -- Mouser #75-36DY103F050AB2A). And it works. I
get about 46VDC.

The problem is that when I hit the flippers a good bit on my test
playfield (driving them with an AC Game Systems build of the PinMame-
HW board), it seems to be dragging the voltage down below the Vmin for
the DC-DC converter powering my microcontroller, causing the system to
reboot/reset.

It's been recommended that I use a bigger transformer and shoot for
more like 80 or 90VDC, and I guess I can go there (the DC-DC converter
will handle it) but I wanted to see what other people are using and if
it's been successful for them before I plunk another $50+ down.

Here's a shot of my power supply: http://flickr.com/photos/preble/502184927/in/set-72157594144190937/

So what sort of power supply are you using?

Adam

[Eli Curtz]

It hasn't arrived yet, but I just ordered a 63v power supply from AnTek
http://www.toroid-transformer.com/
on the theory that I'll need to pick my battles and I wouldn't be
saving much building it myself.

Adam had already told me about his reset issue, so I decided to go for
something a bit beefier than his 43v supply.

The design is practically the same as the PinMame-HW one, which seems
to validate that (and suggests it's pretty standard.)
http://www.toroid-transformer.com/PS-8N63R.pdf
vs
http://membres.lycos.fr/regismalt/43volt.gif (from a French mirror of
pinmame-hw.com)

I'm also thinking of just ordering a separate pc/arcade power supply
for the 5v and 12v. They are insanely cheap, and I won't need to worry
about reseting if my solenoid voltage gets pulled down.

eli

[Adam Preble]

On Jun 10, 1:15 am, Eli Curtz <e...@nuprometheus.com> wrote:
> I'm also thinking of just ordering a separate pc/arcade power supply
> for the 5v and 12v. They are insanely cheap, and I won't need to worry
> about reseting if my solenoid voltage gets pulled down.

Are you thinking about just a brick/wall wart, or perhaps something
slightly more sophisticated? My concern (due to my own lack of
knowledge) about such a solution is how you get a common ground. Can
you just tie the negative/ground outputs of each power supply
together?

Adam

[Eli Curtz]

As should be obvious I am not an Electrical Engineer - me write code.

I was thinking a computer supply, not a wall wart
http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-
Power-Supply

I have no idea if you can actually tie the grounds together if you have
multiple transformers or not. I'll try to contact a hotshot engineer
buddy and get the scoop. All the stuff I've looked at seems to indicate
that grounding voodoo is the number one thing everybody screws up as a
beginner, so I'm probably well on my way.

eli

[Tony @ GLM]

Hi Adam,

My advice would be to make a separate power supply for your digital
hardware.
That's how they do it in pinball machines. The transformer has
multiple secondary windings. This allows them to run multiple voltage
levels, and also to keep the interaction of one set of circuits
separate from another.

For your case, just use another smaller transformer.

If I were going to do it, I might suggest buying a multiple output
switching power supply, as those can deliver insane amounts of current
in a small package. Those require a _lot_ of care in selection and
close attention to loading in order to use them efficiently.

Tony
www.greatlakesmodular.com - Re-Engineered Pinball Parts!

[Popbumper]

I know that there are many approaches to taking on the foundational
power requirements for a pinball machine. I'm curious though why no
one has mentioned using the original transformer and power supply
circuits that have been designed by the manufacturers?

I should get to start on physically building my game this year. My
plan is to use the Gottlieb System 80 power supply / transformer set
up. It's robust enough to take whatever number of coils I want to use
with it and with the reproduction power supply boards in existence, I
can be assured that it will work reliably. And you can't beat the cost
if you're already a collector with hundreds of leftover parts from
previous restoration work. There are others of course, WIlliams system
11 comes to mind. Not really interested in Bally's system since it
integrates coil drivers.

I realize I haven't *built* anything yet so take this all with a grain
of salt.

Nice idea for a group!
Rob Craig

[ge...@pipeline.com.au]

use a system 11 transformer and make your own 2 X bridge rectifier
solution, only the 50volt flipper ground should be left 'floating'
so you have br1 @ 50volts
br2 at 28vdc (other coils + lamps)
6.3 vac GI
you coulds use the 12volts tapping for feature lamps