Adjustable Flashing/Blinking LED Circuit using 555 Timer IC

A tutorial on how to make an Adjustable Flashing/Blinking LED circuit using 555 timer IC and a few other electronic components. This circuit toggles an LED or any output device ON and OFF at regular intervals of time. The duration between successive toggling of LED can be adjusted by using a potentiometer.



Components Required


  • 555 Timer IC

  • LEDs

  • 10uF Capacitor

  • Resistors: 100K, 1K, 220R

  • Prototype soldering board

  • Few wires

  • 9V battery

  • Potentiometer (Optional)



Circuit Diagram




The resistors R1 and R2, along with the capacitor C1 control the blinking rate. While capacitor C1 and resistor R1 influence both On and Off times of the LED, Resistor R2 is responsible only for the On time. So if you want to try out different resistor values and change the flashing rate, you can experiment by changing the value of resistor R2.