Hello,

I'm a student working with the ADXL1001 Accelerometer for vibration measurement (using LabView). I am trying to measure the noise of the sensor. As per my understanding so far, this is what I have done:

*Mounted the sensor

*Measured the output (under no input vibration conditions)

*and then measured the output of the sensor.

The standard deviation of the voltage output signal around the mean gives me the RMS noise of the sensor. I would also like to compare the noise calculated from the Power Spectral Density with this RMS noise. But I am not sure about how I can obtain the RMS voltage from the PSD graph. Could someone please explain me that?

The document that I used as a reference is this one: https://wiki.analog.com/_media/mems/reference_document_on_achieving_best_noise_performance_with_adxl1002.pdf

P.S.: Feel free to correct me if I was wrong anywhere, I'd be happy to learn!

## Top Replies

• Thank you for your post and your use of ADXL1001. To obtain the RMS voltage from the PSD graph, you must first square the values of the graph and then integrate it with the given frequency…

• Hi

Thank you for your post and your use of ADXL1001. To obtain the RMS voltage from the PSD graph, you must first square the values of the graph and then integrate it with the given frequency range of the graph and getting the square root afterwards. For an equation format:

where grms is the RMS value,  is the function that describes the ug/sqrt(Hz) graph and f1 and f2 are the starting and ending frequencies of the Noise Power Spectral Density (PSD) vs. Frequency graph. Since, a normal integration is not possible, I suggest that you look into numerical integration of the sampled values of the graph.

Regards,

JP

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Thank you,