LED Series Resistor Calculator
Calculate the resistor required for an LED circuit using supply voltage, LED forward voltage, and desired current in milliamps.
Always verify circuit designs before implementation.
Examples
- 9V supply, 2V LED, 20mA ⇒ 350 Ω
- 5V supply, 3.2V LED, 25mA ⇒ 72 Ω
FAQ
Why convert milliamps to amps?
Ohm's law requires current in amps for accurate calculation.
What if supply voltage is lower than forward voltage?
The LED won't light; increase supply or use a different LED.
Does resistor wattage matter?
Yes, choose a resistor that can handle the power dissipation.
Can I run multiple LEDs?
For series LEDs, adjust forward voltage accordingly; for parallel, use separate resistors.
Additional Information
No additional information available.