How to wire a Nano Biscotte

[DarthMarr]

8290

the speaker and switch don't have a polarity.

[Crystal Chambers]

Yep..doesn't matter for mom switches or speakers. I believe all you need is a resistor on the LED.

[DarthMarr]

Oops. I forgot to put that in. But resistors are not always needed.

[Forgetful Jedi Knight]

i thought you needed a resistor for the led? so the board will run fine running a Luxeon Rebel with out there being a Resistor? or do i HAVE to have one?

You SHOULD have a resistor for the main LED. Even for the higher Vf LED's, you should have something on them. ;)

[jin starkiller]

i thought you needed a resistor for the led? so the board will run fine running a Luxeon Rebel with out there being a Resistor? or do i HAVE to have one?

yes you will need a resistor for the main led

[Arryck Corso]

The NB has the capability to run the main LED without a resistor but only depending on what color you're using. Red and yellow have low forward voltages and would need the appropriate resistor to make them work. Green, white, and blue have high forward voltages typically close to that of your source voltage. This means they would need a very small resistor which may be difficult to locate.

On page 17 of the manual, the Drive Adjustments section discusses this. The drive parameter defines the maximum drive applied to the main LED. This configurable parameter is designed to allow you to power your main LED without the need of a resistor so long as your LED's forward voltage and your source voltage are relatively close. Which would be for your greens, blues and whites. The idea behind this parameter is if you're using a 3.7v li-ion battery and running green for you main LED the resistor value needed for this is so low that you probably won't be able to find one. The board allows you to "drive" the LED in a manner similar to what the PC and CF have standard.

Basically you need to know what LED you want to use, what its forward voltage is, and what battery you'll use to determine if a resistor is needed or not.

[Darth Vane]

Oops. I forgot to put that in. But resistors are not always needed.

i thought you needed a resistor for the led? so the board will run fine running a Luxeon Rebel with out there being a Resistor? or do i HAVE to have one?

[KingOfDathomir]

how would you apply this formula to tri-rebels?

[TrypWyr]

how would you apply this formula to tri-rebels?

I used a BBW TriR to make a silver blade on a NB saber, but only using the B and W, leaving the second B unused. In that case, simply wire the two dies in parallel and calculate the drive parameter using the Vf of a single die.

So in this instance, I used 3.4v@1000mA for both dies (maybe overdriving the white a little, but it works and I'm okay with that).

R = (3.7 - 3.4) / 2 = 0.15 ohm

Yeah, not gonna find that resistor... so, using Erv's formula in the NB manual:

drive = 1023 * (3.4 / 3.7) = 940

Just remember the caveat from the manual: "Never set the drive under 80% of the maximum value." So never set the drive value below 818.

Okay, I'm still drinking my coffee today but I'm pretty sure my math is good. Someone please correct me if not! :D

[PsHADeadGuy]

I've been thinking about ordering a NB for my saber build, my main LED is 3.4v and I have the lithium ion battery pack that's 3.7v 2600mAh. Do I need a resistor? Or is the difference close enough that it won't fry it?

Also, My momentary switch has one of the accent ring LED's in it, if I want it on constantly, I would run it straight to the battery (with a resistor of course), and then also run my recharge port directly to (and from) the battery?

Thanks for the initial diagram, it has helped me quite a bit.

[Silver Serpent]

I would use a resistor. Fully charged, a li-ion battery puts out around 4.2v.

http://forums.thecustomsabershop.com/showthread.php?2235-Recharge-port-hookup&p=51391#post51391 has the instructions on wiring up a recharge port. Just be sure your switch LED negative is run to the green wire in the diagram (the same as your NB), so that it'll shut off when you insert the kill key.

[PsHADeadGuy]

Thanks so much Silver Serpent! That helps a lot. I'll make sure to get a proper resistor for the LED's.

[Kendrick]

This information is so helpful! For the sake of not making a new thread, I thought this would be a good opportunity to ask a noobish question :confused:, After doing some calculations I was wondering if it would be okay to use a p4 green (4.1v) with 4 NiMH aaa batteries (4.8v) without a resistor if I set the drive adjustment on the NB to 873.8125 from the standard 1023, I believe that's more than the required 80% right?? I just ask because I wanna use the MWS instead of doing this myself and thought it would be pesky to fit a resistor in there

[Forgetful Jedi Knight]

You would need a resistor, because the typical Vf for a green is more like 3.6-3.8V. The 4.1V is the MAX it could be. So a little work is in your future, unless you decide to go with a Li-Ion battery. ;)

[Kendrick]

Fishsticks.. well thank you :) I guess I'm going to have to suck it up! Fortunately I wont have to do any on board soldering though :D ... I've had terrible experiences in the past :x

[Forgetful Jedi Knight]

Fishsticks.. well thank you :) I guess I'm going to have to suck it up! Fortunately I wont have to do any on board soldering though :D ... I've had terrible experiences in the past :x

It takes some skill to do board soldering and do it well.

[Kendrick]

Indeed it does!