Differential mode connection on Arduino Due Analog input

Official Hardware Mega Due
1

Hi!

This is my frist question in the forum... and my english is terrible, so:

I want to read an sine wave input in differential mode connection on my Arduino Due, but Im no sure how must be, and the code neither.

In the image show the tentative connection. I prefer no fry my Arduino Due so I appreciate some help or some links to the appropiate information.

Thanks all of you!

2

Are the two grounds connected? No input to the Due can be less than 0V so your scheme would work with floating grounds but not if the ground is connected.