# DUE maximum I/O 3.3V how does this affect me?

Hello,

I just got my very first Arduino DUE today, what exactly does it mean: "Applying voltages higher than 3.3V to any I/O pin could damage the board".

If I connect a potentiometer to the +5v and GND and then read the values, if I read 4V will my board get damaged?

I'm still a newbie and I want to avoid damaging it.

It is fairly self explanatory.

No more than +3.3V to be applied to ANY pin. Damage to the chip WILL happen if you do.

Warning: Unlike most Arduino boards, the Arduino Due board runs at 3.3V. The maximum voltage that the I/O pins can tolerate is 3.3V. Applying voltages higher than 3.3V to any I/O pin could damage the board.

https://www.arduino.cc/en/Main/ArduinoBoardDue

it means that interfacing the GPIO pins with most exisiting arduino shield circuits should be done through a level converter.

A lot of 'older' arduino shields expect / use 5 volt for their IO but the due uses 3.3V for their IO...

Using a level converter or using optically isolated IO are 2 approaches to interfacing the DUE to higher voltage circuits.

The simplest option is the bidirectional level shifter circuit developed by sparkfun.

https://www.sparkfun.com/products/12009

Alternatively if you are designing your own 'shield' or interface you could use the linked level shifter circuit as a basis for your own design... It is a quite simple and ingenious circuit and just works as intended... the mosfets and resistors are cheap enough to buy in bulk for incorporating a level shifter into your own circuits

scallipus: The 'normal' arduino shields expect / use 5 volt for their IO but the due uses 3.3V for their IO...

Perhaps it would be better to say "The 'older' arduino shields expect / 5 volt" as there are now more 3.3V Arduinos than 5V and well designed shields adapt accordingly, but your point about level conversion is valid.

G

ghlawrence2000:
Perhaps it would be better to say “The ‘older’ arduino shields expect / 5 volt” as there are now more 3.3V Arduinos than 5V and well designed shields adapt accordingly, but your point about level conversion is valid.

G

Cheers, edited accordingly…

On my due, I designed an optically isolated motor control system before I found the ‘level shifter’ circuit… was a bit paranoid about frying my Due so wanted to make sure there was no way the motor circuit could ever possibly back feed into the MCU.

I did buy some level shifters and use them for GPIO, just not for motor control at this stage…