IC555 Astable Mode

The IC555 is a widely used IC. It has two modes of operation. Namely, Astable and monostable mode. In the Monostable mode, a negative clock pulse to the trigger pin (pin 2) will generate a output for the duration depending on the chosen values of the resistors and the capacitor. In the Astable mode of operation, The IC555 generates square waves with a duty cycle and frequency depending on the chosen values of the resistors and capacitor. for the values I chose, I got a pulse for approximately 1 second. with a 66% duty cycle.
In the schematic, the jumper 1 (JP1) represents the output for which I had connected a LED. and jumper 2(JP2) represents the header pin for input supply.

Schematic

PCB design

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