Hello A newbie is here:) I am currently designing a board similar to Arduino. I have a PTC fuse that I would like to use on my voltage line of the USB port, but I realized there is also a capacitor near it which decouples the fuse to ground. Is it necessary? Any special value ? Because I saw Arduino nano has 4.7uF whereas Diecimila has 100nF.
Furthermore, Regarding the diode that we use to prevent currents in wrong directions. Should that diode be placed near the USB port itself? does that even matter?
Thanks in Advance