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LED Resistor Calculator for 12V
Quick guide for 12V LED resistor sizing with practical examples and recommended resistor power margin.
12V practical example
For 3 white LEDs (Vf≈3.1V each) at 15mA, resistor drop is about 2.7V, so R≈180Ω.
Power check
Resistor power is P = I²R. Pick at least 2× margin over calculated dissipation.
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