3

I am trying to build a raspberry pi gameboy emulator with a custom board inside of a gameboy adv sp shell. I decided to use an open-source board made by some guy on the internet and I will be modifying a few things on the board such as the power switch to an OEM power switch for authenticity.

My question is as follows: how could I change the schematic from a DPDT switch to a SPST? Images here:

Apparently the DPDT switch is connected to things like keepalive, +3v, enable, shutdown, and the rest of the connections go to other parts of the board.

OEM SWITCH

BOARD IMAGE OF SWITCH

SCHEMATIC IMAGE OF SWITCH

Vincent Pipitone
  • 41
  • 4
  • The transistor appears to be upside down or else it should be an NPN. – Transistor Mar 23 '19 at 17:56
  • the big question is .... `why?` ........ also, what is `open-source board made by some guy`? – jsotola Mar 23 '19 at 19:10
  • MMBF5460 is a P-channel JFET – Spehro Pefhany Mar 23 '19 at 19:53
  • The two switches have separate purposes, as senor Karas indicates, and the original switch could control a relay as senor Howie indicates, but if what you want is an authentic look(The device being an emulator makes inner authenticity irrelevant), as a second option other than using a DPDT relay controlled by an original switch, you could simply find a DPDT switch that performs like the original(similar dimensions and travel) so that the part exposed to the user can be more authentic. – K H Mar 23 '19 at 20:54
  • Thanks for the comments, I learned a lot and decided it would be best to keep the original power switch. – Vincent Pipitone Mar 24 '19 at 01:50

2 Answers2

4

Use the SPST switch to control a small DPDT relay.

HandyHowie
  • 4,030
  • 1
  • 15
  • 22
2

In this application there is no direct way to replace the DPDT switch with a SPST switch.

If you were clever with electronic circuits, analogue switch components and how to design with them it may be possible to replace the DPDT switch with some circuitry and a SPST switch to toggle it between two states. There is not nearly enough information provided to even be able to suggest a suitable circuit.

Michael Karas
  • 56,889
  • 3
  • 70
  • 138