Self Powerered Neo Bitz and Common Ground.

I need to self power a Neobitz encoder off of my Neo Geo Four Slot.

How should I incorporate the second PSU?

I have to hook the Second PSU into the ground of the first one right?



Any help from you geniouses is apreaciated.

I don't want to blow anything up.

Any reason why you are using a second psu?

Why not just grab the +5 and ground from the 4 slot or current psu?

I am having a hard time getting video output from the AD725 circuit.\
The component Circuit works great.

I am nearly certain that the PSU cannot supply enough power.

norton9478 said:

I am having a hard time getting video output from the AD725 circuit.\
The component Circuit works great.

I am nearly certain that the PSU cannot supply enough power.

Click to expand...

What psu are using to power the 4 slot?

I didn't think the Neobitz drew that much current.

GiLL said:

What psu are using to power the 4 slot?

I didn't think the Neobitz drew that much current.

Click to expand...

I use an Sc200...

IT powers the board and the component stage of the neobitz......

But the voltage drops pretty low.

I know that the ad725 chip is very voltage sensitive.

Have you tried cracking open your sc200 and turning the current up?

Otherwise, if you want to put in a second psu, just wire +5, gnd, what-have-you to the encoder board. No need to connect the grounds or anything between psu's.

I'd think it would be better to just replace the sc200 with a more capable psu instead of having two psu's when you could easily have one.

cheers,
-DT

I'm pretty sure your problem wouldn't be that the SC200 isn't quite gutsy enough to power both the MV-4x and the Neobitz board, rather there’s some sort of wiring issue. The AD72x chips have really low current draw and as far as voltage sensitivity, they readily and safely accept from 4.75 - 5.25v to power up the chip. As far as the Datasheet goes, the current draw is around 30 mA (milliamps), which compared to say 4 full Amps for the 4 slotter, it’s pretty much negligible. I would suggest checking your connections on the Composite and S-Video outputs and failing that get onto JMKurtz for a little after-sales assistance. Good luck with that!!

It still very well could be the sc200 (although it sounds as if moving the neobitz to another psu may not be enough), because others have reported the 4 slot not working properly with the sc200. K'Dash said in another thread that he was able to open his sc200, and adjust the current with some sort of pot inside.

Hopefully you're lack of responses norton means that you've got it fixed by now. Let us know.

cheers again!
-DT

I jacked both the Sc200 and the othe Alut Counterpart.

No Dice.

So to answer my Question,

If I use as second PSU, SHould I ground them both together?

No I believe it would be better to have the grounds isolated. Although you could connect them. I am thinking about in the event of power failure, psu failure, spikes etc. Having the grounds seperate will give some measure of modularity and possibly circuit protection. There is no real reason to connect them.

Think of an arcade cab, in that cab your neobitz is the equivalent of the monitor, and a monitor in a cab has a completely separate psu. They will be grounded together to some extent anyway through the RGB video ground.

So I would just wire the second psu to the neobitz.

cheers,
-DT

Ok, I'll wait and see if any other guru's chime in.

I just thought that without a common ground, Electricty could build up on the neobitz and finnaly discharge through the RGBSync Lines.