Arduino Due I2C devices

Using Arduino General Electronics
1

Hi, just a quick question:

I'm designing a shield for the Arduino Due so of course, that means everything on it needs to be 3.3v compatible.

Does this mean I need voltage dividers / level shifters for the I2C pins as well if I am using them?
If so, how do I need to go about wiring them since there is only a single data line (SDA)?

2

Depends on the sensors you're going to use.
Only the 5volt ones need to be level-shifted, and a 1k:2k2 voltage divider could be enough.

A lot of sensors are now 3.3volt anyway, or have I2C level shifters on the breakout board.

I2C is a two-wire bus.
Both SDA and SCK lines need to be 3.3volt, or level-shifted to 3.3volt.
Leo..

3

So is this what it would look like on a schematic?
(image attached)

postexample.png
postexample.png784×697 2.91 KB

4

For I2C you normally use bi-directional level shifters with two (BSS138) mosfets.
Leo..