user41845: I need to use atmega328P without arduino board, so far I know that I will need 16MHZ Quartz Resonator and two 22nf capacitors. However, I have seen that other people are using atmega328P without capacitors.
What is the role of those capacitors? Can I use atmega328P without capacitors?

user4143: Those specific capacitors form part of the resonant clock oscillator circuit. If you are using a quartz crystal then they are required. You can't do without them.
If you use a 16MHz ceramic resonator, however, they don't need the capacitors (they're built into the resonator).
Also, if you have your ATMega328P on a breadboard the capacitance of the board itself is sometimes enough to "get it working", though as soon as you transfer your circuit to a permanent PCB it will suddenly stop working for no apparent reason.

41845: <p>I need to use atmega328P without arduino board, so far I know that I will need <code>16MHZ Quartz Resonator</code> and two <code>22nf capacitors</code>. However, I have seen that other people are using atmega328P without capacitors.</p>

<p>What is the role of those capacitors? Can I use atmega328P without capacitors?</p>
 4143: <p>Those specific capacitors form part of the resonant clock oscillator circuit. If you are using a quartz crystal then they are required. You can't do without them.</p>

<p>If you use a 16MHz <em>ceramic resonator</em>, however, they don't need the capacitors (they're built into the resonator).</p>

<p>Also, if you have your ATMega328P on a breadboard the capacitance of the board itself is sometimes enough to "get it working", though as soon as you transfer your circuit to a permanent PCB it will suddenly stop working for no apparent reason.</p>
