Current limiting resistor calculatorTypical supply voltage: From molex; 5, 7 and 12 volts Typical LED forward voltages: Ordinary Red LED: 1.7 Volts special red high-brightness, high-efficiency, or low-current: 1.9 Volts Orange or yellow: 2 Volts Green: 2.1 Volts Bright white, emerald green, and most blue-derived (phosphor): 3.4 Volts 430 nM bright blue: 3.5 - 3.8 Volts U.V: 4.6 Volts Current: If you are unsure on the current try 15 mA. For blue, white, and exotic colors try 10 mA. |
Single ledSingle example  |
Leds in seriesSeries example  |
Leds in parallelparallel example  |