LED resistors

[orchidius]

Hi there,

I'm ordering all the parts I'm going to need for my CP today and I just wanted to make sure I don't get the wrong stuff before I actually order the parts. So...

To wire up an RGB LED to the Ledwiz, I need:

-An RGB LED
-2 100ohm resistors, one for the "Green leg" and one for the "Blue leg"
-1 150ohm resistor for the "red leg"

Correct?

EDIT: Also was wondering what angle the LEDs should be. Wiki says 45°, but does that mean at least 45° or just plain 45°? I found some 40° ones and some 100° ones, what would suit the pushbutton needs best?

[Jouster]

You could always order the whole setup from http://groovygamegear.com/webstore/index.php?main_page=product_info&cPath=83&products_id=240']GGG[/url] and save yourself some trouble...

Jouster

[orchidius]

I could yes... But I personally think that the price of those things is worth the "trouble" it would be to solder them up yourself. I need 30, which would cost me around 145$ shipping included... I can do that for less then a third of the price, and don't mind the extra work at all.

Nobody got an answer to this? I see ppl who use a 100ohm resistor for all 3 legs, is that possible too?

[Franco B]

The resistors you require will depend on the specs of the LED, the power source and the way in which wired (single/series/paralell).

We need to know:

The power source (5v or 12v usually)

The forward voltage of each colour anode (presuming its a common cathode LED)

The diode forward current.

How you are wiring the LEDs

[orchidius]

1) The leds will just be wired to a LEDwiz, which means power from the 5v pc supply.

2) Not sure what you mean by that, they're just going to be regular 5mm RGB common + LEDs

3) Sorry to disappoint you again, but I don't know what that is :s

4) LEDs will be wired to the LEDwiz

[Franco B]

Each 'brand' of RGB will differ which is why you need to know the particular specs.

Where are you buying your RGBs from? You should be able to get the specs from the vendor.

[arzoo]

Franco is correct (he knows LEDs!) - to do it right you should know the specs on your RGBs. But assuming you're only wiring one RGB leg to each port on the LEDWiz, using a 100ohm resister on each will most likely work fine. I would just test one and see how it goes.

[gryhnd]

Randy also sells bare LEDs (button blasters he calls them) with the appropriate resistor free, for a whopping $0.49

[orchidius]

@Gryhnd
Only single colored though

Any info on the viewing angle? Ebay has tons of very cheap ones, but the viewing angle is only 20° on most... Would this be an issue with Electric ICE buttons?

[drventure]

One site

http://led.linear1.org/led.wiz

All you need for determining resistor values.

About the viewing angle, if they're going in a button, the button will diffuse the light. Can't imagine the viewing angle would have much of an effect in that case. If they're bare, though, it's another story.

100ohm or 120ohm is usually pretty safe. You might underdrive them and they won't be as bright as they could be.

You just mainly don't want to overdrive them and have em burn up on you (by using too small a resistor value).

Anyone have any thoughts on actually wiring the resistors in. I've put them in on the ledwiz side, and right up next to the LED itself. Technically it doesn't matter, but it seems a little "cleaner" to put them next to the LED so you just have simple wires going into the LEDWiz, not the resistor legs. They're a really pain to solder up either way, or maybe I just don't know the trick?

[orchidius]

Does it make any difference if I get common cathode or common anode? Apart from maybe having to wire them differently?

[Franco B]

One site

http://led.linear1.org/led.wiz

All you need for determining resistor values.

Yes, excellent site

Anyone have any thoughts on actually wiring the resistors in. I've put them in on the ledwiz side, and right up next to the LED itself. Technically it doesn't matter, but it seems a little "cleaner" to put them next to the LED so you just have simple wires going into the LEDWiz, not the resistor legs. They're a really pain to solder up either way, or maybe I just don't know the trick?

I hear you buddy. They can be a PITA to wire up.

Does it make any difference if I get common cathode or common anode? Apart from maybe having to wire them differently?

You need common anode RGBs.

[orchidius]

Thank you all very much for the help, and sorry for the noobish questions

[Franco B]

Your most welcome

If you need any more help don't hesitate to ask.