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Harblar
05-14-2015, 01:50 PM
Hey all. Question for all the electronics gurus out there. I'm working on a new saber idea and I need a little help on the potential wiring end of things.

What I want to do is (using a PC 3.5) use the aux accent pads as triggers for driving a full Power Cree (powered off from the bottom mounted pex's as described in the psuedo color mixing section of the manual). My thought was initially wiring a relay between the aux pads, the onboard pex pads, and the cree, but I'm pretty beginner level on the electronic end of things. I can solder and wire parts in the right place as described on a diagram or calculate needed resistors in a basic circuit, but when it comes to finding the right specialty parts for more advanced things I'm a little lost. Maybe I'm just not looking for the right component or I'm misreading the specs, but my concern is finding a relay that can be effectively triggered and maintained by the power provided by the aux pads.

In the process of trying to find my own solution I happened to take another look at the PEX board (typically used for flash on clash) and noticed the trigger could potentially be switched by the aux pads.

So here's a basic diagram I drew up of how this would work, though I'm not 100% on whether it's right or not. Am I on the right track?

https://lh5.googleusercontent.com/-H4LBMXfEadQ/VVUIIzKPNUI/AAAAAAAANNc/P4Sm6zvIpQk/w1152-h477-no/PEX%2Bwiring%2BDiagram.jpg

Now... I know the first thing you're probably all going to ask is, "Why?"

I assure you, there is a method to my madness. With out going to much into detail on it, one reason is that it allows for one to use the animated (programmable aspect) ability of the aux pads and apply it to a fully driven cree.

So... Possible?

JakeSoft
05-14-2015, 06:44 PM
It seems like what you are proposing should be possible. The PEX boards are basically convenience boards that break out a small FET into a nice easy-to-use package. Assuming the output from the accent pin on the PC 3.5 is adequate and that you include the proper resistor for your LED, it would probably work. I've never done a build with a PC 3.5 (and I'm too lazy to read the manual ;) ), so somebody else will have to confirm your wiring diagram connections to the board, but your wiring from the LED to the PEX looks right.

cvsickle
05-15-2015, 09:30 AM
Possible? Yes. Practical, maybe.

Doing this would only allow the LED to be on when your accent signal was on, but when it IS on, it will be subject to the flicker parameters for your main led. If that's what you want, fine.

Rather than wiring it to the PEX on the bottom of the board, you can just wire it to the main board's negative pad. That will apply the battery voltage, but will be consistently and fully on when your accent signal is on. Obviously, you need to use the correct resistor.

Make sense?

Harblar
05-15-2015, 01:59 PM
It seems like what you are proposing should be possible. The PEX boards are basically convenience boards that break out a small FET into a nice easy-to-use package. Assuming the output from the accent pin on the PC 3.5 is adequate and that you include the proper resistor for your LED, it would probably work. I've never done a build with a PC 3.5 (and I'm too lazy to read the manual ;) ), so somebody else will have to confirm your wiring diagram connections to the board, but your wiring from the LED to the PEX looks right.

The Aux pads are rated to output upto 3.3V @ 18ma and the PEX switches at 3.3v, so it should work.


Possible? Yes. Practical, maybe.

Doing this would only allow the LED to be on when your accent signal was on, but when it IS on, it will be subject to the flicker parameters for your main led. If that's what you want, fine.


Yep... That's exactly what I'm shooting for. :-)


Rather than wiring it to the PEX on the bottom of the board, you can just wire it to the main board's negative pad. That will apply the battery voltage, but will be consistently and fully on when your accent signal is on. Obviously, you need to use the correct resistor.

Make sense?

Yep. Just didn't bother to throw the resistor into the diagram. Aside from that, though, the wiring looks like it will work?

Can't wait to get my parts together and get this working! Should be cool.

Thanks! :D

cvsickle
05-15-2015, 02:04 PM
I don't see why it wouldn't work, but you may want to wait to hear from an expert before you try it.

Harblar
05-15-2015, 02:47 PM
Will do. Probably going to be a week or so before I get the parts together and give it a try.

Thanks for at least confirming that I'm on the right path! :-)