555 Timer LED Flasher
A blinking light with no code — just a 555, resistors and a capacitor.
Overview
The 555 in astable mode switches its output at a rate set by two resistors and a capacitor. The best first circuit for learning how parts work together.
Build Steps
Place the 555
Seat it across the breadboard gap, pin 8 to +9 V, pin 1 to ground, pin 4 to +9 V.
Add timing parts
1 kΩ from pin 7 to +9 V, 10 kΩ between pins 7 and 6, link 6 and 2, and a 100 µF capacitor from pin 2 to ground.
Connect the LED
From pin 3 through a 220 Ω resistor to the LED, then ground.
Change the speed
Swap the capacitor or resistor to see how the blink rate changes.
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