Electronic circuits that use the 555 Timer

555 Timer Circuits

555 Timers are fun and a great way to start learning electronics

Flashing LED Circuit

A Circuit that flashes an LED on and off.


This circuit uses the 555 timer in an Astable operating mode which generates a continuous output via Pin 3 in the form of a square wave. This turns the LED (D1) on and off. The speed at which the LED (D1) is turned on and off is set by the values of R1 and R2.


Flashing LED Circuit


This video walks you through building this circuit using a breadboard.

Parts List

1x - NE555 Bipolar Timer
1x - LED (Red)
1x - 470K Resistor (1/4W)
2x - 1K Resistor (1/4W)
1x - 1µF Electrolytic Capacitor (16V)
1x - 9V Voltage Battery

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