Arduino Analog/Digital Pin Protection


I would like to protect my inputs ( Analog and digital ) from user errors. I would like to limit thing to 0-5V and to 0.5A. Anyway has a description of what can be done electrically to protect input to make sure that the user wont screwed up everything?



Keeping it within 5V is fine but isn't 1A going to be a bit much? Won't that damage the arduino?

yep it is too high.

That's why I wrote:-

By the way:-

and to 0.5A.

In this context is meaningless.

as always, thanx Mike, I will read it.


will this:

introduce delay in the 0-5V signal sampling?



Yes by about 2.2nS, I don't think that is much of an issue do you?

Nano seconds. I think it would be fine ;)

You can calculate the time delay by looking at the time constant. This is simply the multiplication of the values of the resistor and the capacitor in Ohms and Farads. The result is in the units of time, something that has always fascinated me even though I know the equations and the derivation.

so 22R X 100pF = 2.2nS