max voltage on digital pin???

Forum 2005-2010 (read only) General Frequently-Asked Questions
1

Does anyone know what the max input voltage allowed on a digital pin?

Im using a mega and i have 5.4V potentially going to the pin?

Is this enough to damage the pin??

if so, what is the min voltage a digital input can receive to recognise a state change??

Thanks in advance,

VR

2

The ATmega328 datasheet says input voltages must not exceed 5.5V. That's an absolute maximum and should not be considered a normal operating condition. 5.4V should be OK, but it wouldn't hurt to put a resistor in series to limit current in case it spikes for some reason.

The minimum voltage for a logic high on a digital I/O pin is 3V. The maximum voltage for a logic low is 1.5V.

3

Thanks RP.

I didnt even think to check the datasheet! Doh!!! time for a beer!!

VR

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