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Blinking LED psd

a 555 timer in astable operating mode

Recent activity:

  • psd board processed7 years ago
  • psd schematic processed7 years ago
  • psd board received7 years ago
  • psd schematic received7 years ago
  • psd pushed to7 years ago
  • psd board processed7 years ago

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This is effectively the "hello world" of the 555 Timer, and the basis of a number of other circuits. The speed and duration of the blinking are governed by the values [R1] and [R2].




Bill of Materials

Designator Value Description
C1 1µF Electrolytic capacitor; 1µF; voltage 10V
R1 1kΩ Resistor
R2 1kΩ Resistor
R3 470kΩ Resistor
LED1 LED-05G 5mm LED green
U1 NE555 555 Timer
VCC1 9V 9V battery, PP3 or similar



This project is published under the terms of the BSD License licence.