Basic Electricity 101 question?
#1
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Basic Electricity 101 question?
I need to use a single l.e.d. light on a 12v. power supply. As an example, If the light has a max rating of 3.6v how do I figure what resistor to use? I'm sure there must be a simple formula. Thanks for your help.
#2
http://www.kpsec.freeuk.com/components/led.htm
http://www.llamma.com/xbox360/mods/H...20an%20LED.htm
http://ledcalc.com/
http://www.llamma.com/xbox360/mods/H...20an%20LED.htm
http://ledcalc.com/
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Most LED's have a 1.6 to 2.5Vdrop by themselves.....but usually only handle 5ma to 50ma max. Sounds like there may be a resistor in there already? Do you have a Part Number or something?
#5
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R = (12V - 3.6V) / 0.02A = 400 ohm resistor
Go with a 500 OHM 1/4 watt
Go with a 500 OHM 1/4 watt