Power handling: the AC to DC power supply
Early on I decided it would be neat to keep all the power handling inside the case. The original Playstation uses what looks like figure 8 connector for power, and this connector is directly soldered onto the power board.
So in order to replace this thing, I needed a proper figure 8 connector, and the cable that came with it. The original connector was a bit rusty and I decided to get this build brand new components.
These components were bought from element14, for respectively S$3.88 and S$0.95. I’ve included the full manufacturer’s reference if you’re looking for them.
Getting AC power into the case is of course completely useless as we have to supply 5V DC to the Pi. And not only that, the Raspberry Pi 3 is now a diva that requires 2.5 amps power supply. At full load, and with USB gamepads connected to them, you need quite a beefy 5V unit. There are a lot of power supplies out there but honestly on this type of thing you cannot buy cheap. Some Chinese made 5V 3A AC/DC power supplies bought from eBay or Aliexpress probably cannot deliver this power rating at all, and you’ll be stuck with voltage drops and system instabilities. For this build, I went all out and got this very neat 5V / 3A enclosed power supply unit from Tracopower.
At S$31.71 a pop it is definitely not cheap -in fact it’s the most expensive component in there-, but I am buying peace of mind that I will not burn the house down with a power supply that can barely keep up.
Finally, I tried mounting the connector on a laser cut acrylic shaped like the original Playstation power board PCB, and measured that the power supply properly output 5V. The voltage can be adjusted but since the unit was pushing 5.04V out of the box I left it as is.
Power button: ATXRaspi
While you could technically connect the 5V output of the power supply directly onto the 5V rail of the Raspberry Pi, that would be a terrible idea. As soon as the power would be disconnected, the Pi would die in an unknown state. This generally leads to corrupted SD cards and honestly the last thing you want after spending 10h+ on Castlevania (or anything else), is a completely lost and unrecoverable save game. So you need a little power board that will shut off the power to the Pi only when the board has properly shut down. There are quite a few boards that can do that but I chose the ATXRaspi for two main reasons:
- It can power off or reset the Pi through a pushbutton.
- It can be connected to a power LED.
With international shipping, the board came out at US$29.90.
The button and LED were mounted where the original components were. I could not reuse the original Playstation power button because it is a latch button. ATXRaspi will only work with a push button. Both components were bought from a local electronic shop, and came in under S$3.
January 2017 update: Starting from the revision 2.7 of the ATXRaspi, the board fully supports reset and power latch buttons. Check them out!
Putting it all back together, unit tested with the Raspberry Pi in there: all is fine and working!