powering the naomi and the i/o board with different psu's

[edwin128]

Hello.

I was wondering if there would any issue if I provided power to the naomi and the sega i/o with two different supplies.

Cheers,

 

[twistedsymphony]

no problem, but you must tie the grounds together or at least ensure that the ground on the JVS port makes a solid connection on the NAOMI main board.

 

[edwin128]

no problem, but you must tie the grounds together or at least ensure that the ground on the JVS port makes a solid connection on the NAOMI main board.

ok. thx. what is in your opinion to do it? is it joining the two grounds cables enough?

 

[twistedsymphony]

they just need to have a common reference point for the logic/communication to work properly.

 

[RealMFnG]

they just need to have a common reference point for the logic/communication to work properly.

So expanding from that, will it work if the common ground/reference point is at the power distribution block? Given that the power distribution block is situated right after AC Line-in and between the Standard Arcade Switching PSU?

 

[twistedsymphony]

Earth ground isn't necessarily the same ground as the output from your PSU. In some devices there is potential between then and mixing them can be dangerous.

 

[RealMFnG]

I am onboard with you on using the separate 3.3v PSU. It is probably the cheapest alternative for supplying power to the NAOMI. So how do we make this work?

Do we tie the grounds coming off the standard arcade switching PSU to the ground coming off the 3.3v PSU with say a power barrier or distribution block. Then from there, we run ground to the JAMMA harness, lights, controllers, NAOMI, etc?

 

[twistedsymphony]

the ground pins on the JVS connector are already all tied together on the filter board so really you don't need to do anything special aside from making sure you run ground wires from both PSUs to the JVS connectors.

 

[Gakman]

I've already used 2 different PSU, with no link. Cabinet PSU for I/O and sound amp and another PSU for mainboard, and no problem (Lindbergh PSU for a Lindbergh board for exemple). Is there a risk?

 

[twistedsymphony]

I've already used 2 different PSU, with no link. Cabinet PSU for I/O and sound amp and another PSU for mainboard, and no problem

Technically speaking the ground wire on the the JVS (usb) cable should make the ground link between the game PCB and the I/O PCB. In my experience however this connection is sometimes flakey which is why I recommended using a meter to test that there is good ground connectivity before relying on this.

Audio boards generally isolate the audio grounds from power grounds anyway and they typically use separate power supplies. so this isn't a big deal. and if the audio grounds aren't isolated, well then they're providing the ground link so you're all set there.