FluxBench

LED I-V Curve Demo

v1.0 simulator

Visualize the current-voltage relationship of LEDs and understand forward voltage

LED I-V Curve Demo
Volts on X-axis, Amps on Y-axis. The LED has a forward-voltage "knee". Add series resistance to make the current rise less steeply.
Sweeps supply voltage from 0 V to this value.
Scale only. The math is unchanged.
220 Ω
Without resistance, current increases extremely fast once the LED turns on. Adding resistance makes the I-V curve less steep.
LED only
LED + series resistor

LED I-V Curve Demo

Visualize the Current-Voltage (I-V) relationship of LEDs and understand forward Voltage characteristics.

How to use

Adjust the parameters to see how different LEDs behave:

The graph shows the I-V curve, demonstrating how Current changes with Voltage.

Examples

Standard Red LED

High-Power White LED

FAQ

Q: Why does the LED have a forward Voltage? A: LEDs are diodes - they have a characteristic Voltage drop that must be exceeded before significant Current flows.

Q: What happens if I don’t use a Resistor? A: Without a current-limiting Resistor, the LED will draw too much Current and be destroyed.