In this experiment, you are going to build a dimmer circuit for an LED.
Using a potentiometer, you can change the resistance in a circuit and thereby change the current flowing in this circuit. The brightness of the LED is decided by the amount of current flowing, which means you can control the brightness of the LED with the potentiometer.
The Circuit
The potentiometer changes the resistance and thereby the amount of current flowing through the LED. Since the brightness of the LED is decided by the amount of current flowing, you an control the brightness of the LED with the potentiometer.
The extra resistor is there to make sure the resistance never gets too low. If the resistance is too low, the current will be too high and break the LED.
Parts List
| Reference | Value |
|---|---|
| Battery | 9V |
| LED | Light-Emitting Diode |
| Potentiometer | 100 kΩ |
| Resistor | 470 |
The Layout
You can build this simple dimmer circuit as shown below.
Your LED should be very bright when the potentiometer is on one side, and it should be almost off on the other side. But note that some LEDs will have a small light even with very little current, so you might still see a dim light.
