LIS2DH12: do I need a different accelerometer?

[goreandmiller]

Posted on February 28, 2017 at 00:33

Hey,

   In my application there is a lot of high frequency vibration that I am not interested in. The goal is to detect acceleration along a single axis that lasts 200ms or longer, but is generally between 1/2 and 1/10 the magnitude of the noise (vibration readings). Finally, for performance reasons it is not feasible to read all the data from the accelerometer, an interrupt should only trigger when it is likely an event has occurred. 

   What I am trying currently: Stream to FIFO mode, adjusting threshold and duration in both 6D and AOI modes. 6D fails to trigger because vibrations send the reported acceleration bouncing back and forth between positive and negative values. AOI will trigger constantly because of the large magnitude of the vibrations. Is there anything else worth trying before looking for a different product? It seems like a product with a built in low-pass filter could be required. 

Thanks!

[Miroslav BATEK]

Posted on February 28, 2017 at 09:51

I'm afraid that the LIS2DH12 is not suitable for your application. You would need to use accelerometer with low-pass filter, for example

http://www.st.com/content/st_com/en/products/mems-and-sensors/inemo-inertial-modules/lsm6dsl.html

. You can check the

http://www.st.com/resource/en/datasheet/lsm6dsl.pdf

if it suits your needs.

Just to clarify LIS2DH12 has three interrupt modes:

1. OR combination
2. AND combination
3. 6D position recognition