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Hey, /g/uys, was wondering if any of you could give me some helpful information on how to determine the LED lights I need to replace the ones in a PC fan with a different colour. I don't know the forward voltage or milliamps or anything, but it's a 12v pc fan.
TLDR: blue to red LED PC fan conversion
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>>58760872
Ones in your pic are pretty much all, the fucking same from memory. Did you even try?
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it's litteraly grade 7 physics math
https://en.wikipedia.org/wiki/Ohm's_law
http://www.theledlight.com/LED101.html
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>>58760929
So what?
The blue LEDs are probably on 3.6V and he needs 2V
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>>58760929
LEDs are semiconductors. They don't follow Ohm's law.
>>58760872
LEDs like you pictured are usually:
Red,Yellow: 2v,30mA
Green,Blue,White: 3v,20mA
If you're replacing ones in the same group don't worry about anything. If you're replacing 3v ones with 2v ones you'll need a larger series resistor. I can't tell you which one without knowing how many LEDs there are. If you're replacing 2v ones with 3v ones you could have a problem because the total voltage drop could be greater than 12v. You'd need to put in fewer LEDs or not have them all in series.
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>>58761319
Red and yellow will still be 20mA
Pretty much all 5mm LEDs are 20mA
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Can't you just put an additional series resistor that drops the difference in forward voltage?
So probably something like (3,2V-2,0V)/0.02A = 60Ohm
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