Petit Crouton v3 with 10w led engine color mixing.

[RavenXp]

Hi guys. I'm jumping into building a saber with both feet, and a have a couple of questions. One, with a 7.4v Li-ion 2600mAh 18650 power source, and using the color extender board for the petit crouton, will I need resistors for the LED? What is the default output voltage on the main LED channels on the petit crouton?(So I can find the correct resistors) And does anyone have a map of which pads correspond to which color on the LED?

Thank you in advance.

[Forgetful Jedi Knight]

First, Welcome to the Forums.

No, the PC and the CeX will handle the voltage regulation for you. The voltages are auto sensed by the boards.

You would have to test the individual LED's to figure out which is which. if you have a bench PSU, it's easy enough to do. If you don't, get a 2 AA battery holder and put in 2 AA batteries (not rechargeable) and then test out each set of pads. Touching the wires for a second will help you figure out which LED is which.

[TrypWyr]

No resistors needed, all three channels have voltage regulators. You will need to set the current in the config file or in RICE, but voltage is chosen by the regulators. (This only applies to the main high-power LED dice, not the accent LEDS... they will still need a resistor.) As for the color channel pads, I believe you can set them in the config/RICE to whichever order you wire them (i.e. RGB, RBG, BRG, BGR, GRB, or GBR). Check out pages 30 and 42 in the PC3 manual for more info.

Good luck! :D

EDIT: FJK beat to the punch, with more great info! :) As for checking the die color, you can also use the continuity setting on your multimeter and touch the + and - pads with your leads. Just enough current to barely light the die, but enough to see color (at least on P4s and TriRebels...).

[Forgetful Jedi Knight]

No resistors needed, all three channels have voltage regulators. You will need to set the current in the config file or in RICE, but voltage is chosen by the regulators. (This only applies to the main high-power LED dice, not the accent LEDS... they will still need a resistor.) As for the color channel pads, I believe you can set them in the config/RICE to whichever order you wire them (i.e. RGB, RBG, BRG, BGR, GRB, or GBR). Check out pages 30 and 42 in the PC3 manual for more info.


Don't always assume that people will be using R.I.C.E. especially if they are doing their very first build. ;)

[RavenXp]

Thanks for the advice guys. I have a multimeter at least, so I'll try that. I'm still in the planning and money saving stage, so it'll be a while till I can show this saber off. Will be back if I have any more questions.

[RavenXp]

Don't always assume that people will be using R.I.C.E. especially if they are doing their very first build. ;)

I'm planning on using R.I.C.E. I want to dismantle the saber as little as possible once complete.

[TrypWyr]

Don't always assume that people will be using R.I.C.E. especially if they are doing their very first build. ;)


I'm planning on using R.I.C.E. I want to dismantle the saber as little as possible once complete.

Highly recommended... if you are comfortable enough to do a full PC3 with CEx, RICE is a very small part to add for great (and FUN!) gain. Just be sure that you are up to the challenge for this as a first build, it can be quite daunting at first (speaking from experience...). ;)

[Forgetful Jedi Knight]

I'm planning on using R.I.C.E. I want to dismantle the saber as little as possible once complete.

You have a whole lot of reading ahead of you.

[RavenXp]

Highly recommended... if you are comfortable enough to do a full PC3 with CEx, RICE is a very small part to add for great (and FUN!) gain. Just be sure that you are up to the challenge for this as a first build, it can be quite daunting at first (speaking from experience...). ;)



You have a whole lot of reading ahead of you.

I have past experience on working with soldering on printed circuit boards (Robotics, LED game controller lighting, etc.). Needed a new project for the summer and this seemed like a good fit.

[Kyaryo Ysoyav]

JFK, can the LED testing be done with a AAA battery? I remember identifying LED colors when doing my first saber with a AA and nearly going blind when the first one lit up. If not, RavenXP, you should put a couple of paper towels over the top when you test or something. Then you'll get the color, but not the eye damage. :)

[Forgetful Jedi Knight]

Yes, It could be done but you would likely need 2 of them. Using paper towel over the LED is a good idea.

[Silver Serpent]

I always put on a pair of sunglasses when I color-check my LEDs. I also try to avoid looking directly at the LED when I do it.

[RavenXp]

I have a set of laser safety specs that I got with my Arctic that I can use to protect my eyes.

[mikec]

And does anyone have a map of which pads correspond to which color on the LED?

Thank you in advance.

All the LEDEngin data sheets are at: http://www.ledengin.com/products/emitters#LZ4

These are not only good reading...there is a pinout of the MCPCB in each. For example, if you have an RGBA LEDEngin, it's on the second to last page http://www.ledengin.com/files/products/LZ4/LZ4-00MA00.pdf

I would strongly recommend using that rather than blindly (no pun intended) testing. The advice here to protect your eyes is very good.

However, in addition, LEDs are diodes and have polarity. At least with smaller ones, you can damage them if you run current through them backwards, i.e. connect your B+ to the cathode and provide a return path on the anode. There is a good chance that you will create this scenario if you are running through all the pads trying to figure out which does what. It may be fine but I wouldn't risk it with a $15+ LED.

[RavenXp]

All the LEDEngin data sheets are at: http://www.ledengin.com/products/emitters#LZ4

These are not only good reading...there is a pinout of the MCPCB in each. For example, if you have an RGBA LEDEngin, it's on the second to last page http://www.ledengin.com/files/products/LZ4/LZ4-00MA00.pdf

I would strongly recommend using that rather than blindly (no pun intended) testing. The advice here to protect your eyes is very good.

However, in addition, LEDs are diodes and have polarity. At least with smaller ones, you can damage them if you run current through them backwards, i.e. connect your B+ to the cathode and provide a return path on the anode. There is a good chance that you will create this scenario if you are running through all the pads trying to figure out which does what. It may be fine but I wouldn't risk it with a $15+ LED.

I did have a look at that info before I posted, only shows channels on that chart, not what color those channels are. And I'm not worried about getting the wrong polarity, since that's printed on the star board.

[RavenXp]

Wait, going over it again it says what color is what in a different chart halfway through. Die A is blue, B Is red, C is green, D is white/amber.

Thanks for making me take a second look, will post an image of the map out next chance I get then verify it when I get the LEDs.

[Obi1]

If you are unsure you can use the diode/continuity dial of your multimeter to test the color, it has been hinted at by Forgetful Jedi Knight (the Boss here I guess...?), but maybe overlooked. It's there to test connectivity/shorts/and diodes, and a LED is a diode. It drives through a very small current, so the LED's will barely lit up, just enough to recognise the colour. No chance of damaging by wrong polarity, although as pointed out by RavenXP, the polarity is printed on the PCB anyway.
I guess everyone having in mind to build a saber has a multimeter, I would not even touch that soldering iron without...
(before someone thinks I'm so smart, I did find it out the hard way after I nearly burnt out my eyes with the 2xAA test method... now I use the multimeter AND have protective Googles on my workbench