Timing circuit for Arduino


  • ATMega328P-PU - preloaded with Arduino bootloader.
  • 22pf Capacitors (2) (in the diagram they’re blue, but the component I bought were actually orange – no difference. There is no positive or negative to these).
  • 16 MHZ crystal.

For brevity, I haven’t shown the power regulator in the diagram below, but you should of course already have that bit finished.


Timing circuit for Arduino schematically

This part is the core of an Arduino – the microcontroller. The 16mHz crystal provides a constant timing signal which pushes each cycle of the circuit.


Timing circuit for Arduino

Also to make things easier on yourself, either purchase some of these Adafruit pinout labels ($2.95 for 10):


Adafruit pinout labels

Or make your own. Here is a PDF if you have sticky label sheets: Atmega382printout.pdf


ATMega328P-PU printout

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