|
what is the operating voltage and amperage for the LED? Typically, your LED formula should be:
R=(Vs-Vl)/i
Vs=Voltage supply
Vl=Voltage LED draws
i= current LED draws (in amps)
for example, lets say you have an LED that operates at 3.7 volts and draws 0.03 amps(30milliamps) and the car provides 12.4 volts dc:
(12.4-3.7)/0.03 = 290
Then, if you want to make it dimmer by 25% multiply the answer by 1.25 to increase the resistance to 362.5 ohms.
If you cannot find a resistor that is equal to your answer, just round up to the nearest one.
Hope this helps
|