LIS2DTW12 Aliasing cut off

[RStra]

Hello,

I'm using an LIS2DTW12 and I don't understand very well which is the cut off frequency.

I'm quite confused because from this picture seems that the anti aliasing filter has cut off frequency fixed to 400 Hz :

 

Then in this table the cut off frequency after the LPF1 and LPF2 seems ODR/2:

I'm interested in the 0-100Hz part of the acceleration so my ODR is 200 Hz.

I want know if the part of the acceleration above 100Hz is cut off or if only the part above 400Hz is cut and then there will be aliasing.

Regards,

Riccardo

[Eleon BORLINI]

Hi Riccardo @RStra​ ,

To answer your question:

>> I want know if the part of the acceleration above 100Hz is cut off or if only the part above 400Hz is cut and then there will be aliasing.

Frequencies above 100Hz will be cut from Nyquist theorem. Since the out-of-band power will be in any case not equal to zero, there will be the possibility of some alias effect coming from strong tones above 100Hz, especially in the 100Hz-400Hz band.

-Eleon

[RStra]

Hello,

thank you for your response, so the anti aliasing filter has a cut off frequency of 400Hz. To reduce the aliasing should I increase the ODR to 800Hz or 1600Hz ?

[Eleon BORLINI]

Hi @RStra​ ,

yes, it can be a solution.

-Eleon