The best way to regulate the brightness of an LED
Do you wish to regulate the brightness of your Gentle-Emitting Diode (LED)? If we break it right down to probably the most primary, there are two methods to alter the brightness of an LED:
- Altering the resistance worth.
- Turning it on and off quick (Utilizing PWM).
Beneath I’ll clarify the 2 choices and present you circuits you may construct.

Possibility 1: Change the resistor worth
The brightness of an LED is determined by the present by it. A resistor in sequence with the LED units the present. Within the circuit under, you may see the essential setup for controlling an LED:

A potentiometer is a variable resistor that you should use to alter the brightness of the LED. Simply add the potentiometer in sequence with the LED. Whenever you regulate the knob of the potentiometer, the brightness of the LED will change.

Possibility 2: Flip it on and off quick (PWM)
One other technique is to show the LED on and off quick. Perhaps a number of hundred occasions per second. Often, you wish to use a microcontroller for this. By adjusting the proportion the LED is on versus off, it is going to seem to the attention that the brightness modifications.
This technique is known as Pulse-Width Modulation (PWM).
It’s additionally attainable to create a PWM sign with a 555 timer. Right here’s a pattern circuit:

SW1 is an non-compulsory button that you should use to have two completely different obligation cycles. I used it to regulate a servo motor in two completely different positions.
Word that the obligation cycle can’t be decrease than the obligation cycle of the primary 555 Timer (that units the frequency). So be sure to use elements which have low sufficient OFF time for the obligation cycle you wish to use