Need help wiring up LED's in my DDR pad

[UG0TB4NN3D]

Hi,

I recently made a DDR pad for use with my computer, and I was planning on putting LED's in the arrow wells for  step-on-light-up effect. My first thought was to just put the ground straight to the LED and then run the + wire straight through the contacts that signal the controller. However, that would be putting 12v through the controller as well. Would there be any way I could perhaps put a resistor on it, or something else (I'm not too electric savvy), to keep that 12v from running to the controller?

A drawing of an arrow well will be attached, and I will explain the LED route I was thinking about taking.

The 12v + wire would be running through the + arrow well wire, leaving the - arrow well wire for the LED, and the 12v - wire would be connected straight to the LED, once the arrow was stepped on, it would connect the + and - arrow well wire, completing the circuit for the LED and controller.

If there is any way I can do this without running 12v into the controller, I would love for someone to explain it.


Thanks.

 

[pseudolobster]

you say you made this?

what kind of switches did you use for the pads?

a lot of pushbuttons will be double pole, ie they can switch two independent circuits at a time... so you can just run a separate 12v line to the led's without touching the controller circuit.

this pic for example is a double throw double pole pushbutton with six pins:

it switches two independent circuits and has positions for both open and closed, so you could even do like a dual colored thing... blue pads that when you step on them turn red or whatnot.

 

[UG0TB4NN3D]

The switch design was 16 screws, 8 + and 8 -, there are 4 screws on each side, 2 + and 2 -.

 

[UG0TB4NN3D]

Here's a picture of the real arrow well. I couldn't figure out how to modify the first post and keep both images, so here's the real arrow.

 

[pseudolobster]

oh, I see...

I take it there's some kind of metal plate on the bottom of the pad that makes contacts between the screws?

just drill two more screws in, and use those.. just don't connect them to the rest of the circuit.

 

[UG0TB4NN3D]

There's a steel plate on the bottom of the arrow that connects those screws together, yes, but that would still be sending the 12v through the controller.

Would you happen to know the formula to calculate what resistor I would need to bring 12v down to 0.5v?