DreamPSU

Ted, does your board have inputs for a soft power on/power off? I've been tossing around some stuff for a Dreamcast wireless controller, and it'd be cool to be able to turn on the Dreamcast using said controller. I suppose I could use a relay in-place of the power switch, but it seems like overkill. Also, are your 3.3v and 5v outputs always on, or only on when the outputs to the Dreamcast are on?

 

good idea and it will be an option you can't have with pico psu. If it's possible.

 

Soft power on is possible and fairly easy to implement with a PicoPSU. The PicoPSU has a always on 5v feed that can be used as a power source for a microcontroller. The microcontroller can pull the enable pin low/high to turn on the PicoPSU and the system will turn on. It's pretty much how computers handle turning on and off.

 

I am just the messenger, this is not my work so unable to pass comment...

Ted.

 

Whoops, sorry! =)

That was one of my thoughts too. I toyed around with designing a PCB similar in size to the DreamPSU, but with an ATX header on it that you'd plug a PicoPSU into. Based on some other reports, it might need some filtering on the 12V line, since people seem to have issues with PicoPSU setups at times. Aside from that, it'd basically be a carrier board. My concern with such a board would be the mounting of it, since the PicoPSU doesn't have any mounting points. Leaving it secured only by the ATX connector might put a lot of strain on the carrier board's ATX connector.

 

Thats exactly how its intended to be mounted though. I also started on exactly this project as well, before deciding to just go from scratch.

 

You could make the PCB long enough to engage the stand off and middle clip the original psu used. It would add cost the the board but it would give a much more stability to the board.

I looked into making a drop in replacement that had the ac to DC converter inside the system.
I was having problems sourcing the ICE C7 connector in the polarized variant the Dreamcast uses. I did find a nice prefab 85-240vac to 12vdc 30w board mount stepdown unit that was a perfect size for my project. I was going to go with a Texas Instruments solution for power to the system. I planned on using the same cable solution I used for my PicoPSU mount to interface with the system. I just didn't have the time or cash to drop into the project so I shelved it to come back to later.

 

Indeed; a common ATX connector (on the motherboard side) would be vertical (or perpendicular to the motherboard), so I assume you get additional support from the plastic housing touching the board. For the DC though, I was planning to use a right-angle ATX connector (I assume you were thinking the same thing). Since the only support on a right-angle connector would be the solder joints, the PicoPSU would need to be mounted somewhere so that the solder joints on the carrier board don't incur stress. A 3D printed mounting plate would probably suffice; in fact, Collingall already designed one (which looks awesome, BTW): https://www.thingiverse.com/thing:2308511

Edit: Collingall posted at the same time! =) I'd thought about doing a total redesign of the power supply as well; however, I don't have enough electrical engineering knowledge to design one properly.

 

Thanks I don't know that.

 

This one looks like it might work: https://www.digikey.com/product-detail/en/switchcraft-inc/RAPC322X/SC1597-ND/1832420
There's another here that looks closer to the one the DC uses, but has a 17-week lead time: https://www.digikey.com/product-detail/en/qualtek/770W-X2-10/Q273-ND/299900

At any rate, I'm glad others (that are more capable EEs than I am) are thinking about this as well.

 

Thanks for taking a look. Those ones are my backups, they are the non-polarized standard ones. My goal is that you would be able to use your original power cable with the square on one side. I found one on mouser, I believe, but it was wasn't a 90° mount.

Thanks for the compliment on my mount I wanted it to be clean and require no system modification to install.

 

Do you know how where I can find an "ATX connector" for dreamcast like the original psu in order to connect connect the 12V/5V/",3V and ground to the dreamcast. I used a standard ATX connector for pc mother board but there is probably better things to do.

 

Its a Molex Mini Fit JR connector - http://www.molex.com/molex/products/datasheet.jsp?part=active/0050361667_CRIMP_HOUSINGS.xml

So look at mating products for the above link.

 

This is the wire mount connector I used to interface with the Dreamcast power connector.
https://www.digikey.com/products/en?keywords=A1953-ND

 

Ah, I think I misunderstood what he was saying as he said an ATX connector.

 

The atx thing threw me for a loop too.

 

Sorry my asked wasn't obvious. But I didn't know the name of the connector.
Thanks for the link.

 

The proper connector is the Molex KK series, with a pitch of 3.96mm, as the original on the board is also a molex part.

But the TE one will work fine.

 

I believe the stock Dreamcast power supply uses this connector to interface with the pins on the mainboard:
Mouser Link: http://www.mouser.com/Search/Produc...066virtualkey53810000virtualkey538-09-52-1066
Datasheet: http://www.mouser.com/ds/2/276/0009521066_PCB_RECEPTACLES-156638.pdf

 

Looks about right, but dosent that one have 90 degrees bent pins. Wouldnt the pins have to be straight, like on this old pinnball connector? http://www.marcospecialties.com/pinball-parts/CFREH10