Konubinix' opinionated web of thoughts

LED Circuit

fleeting

LED circuit - Wikipedia [2021-01-31 Sun 10:45]

Typically, the forward voltage of an LED is between 1.8 and 3.3 volts. It varies by the color of the LED. A red LED typically drops around 1.7 to 2.0 volts, but since both voltage drop and light frequency increase with band gap, a blue LED may drop around 3 to 3.3 volts.

  • R = (Vpower - Vled) / Iled

[2021-01-31 Sun 10:44]

20 mA (0.020A) is common for many small LEDs

Then, as a rule of thumb, because the voltage of the LED is around 2 and the current can be 5mA without harm, I can always start with the resistance of value (V - 2) / 0.005 = (V -2) * 200.