What is the right Accelerometer for my application?

Automation and Control Sensors Transducers
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1

I am designing a sensor to measure vibration from industrial equipment.
The main characteristics of the accelerometer are listed below:

  • Acceleration Range - up to 8g
  • Type - Digital
  • Output Type - I²C, SPI
  • Axis - X / Y / Z
  • Bandwidth - minimum of 1.6KHz (as higher the better)
  • Resolution - 16 bits

I found a lot of accelerometer that meet the specifications above, although I am not being able to understand how can I guarantee a good resolution in high frequencies of the accelerometer.
I already tested the MPU9250 in a shaker and the results in low frequency (until 150Hz) is reasonable, although in high frequencies (from 150Hz until 1kHz) it is horrible as shown below:

image
ps- the blue dots are the reference accelerometer (piezoeletric) and the orange dot is the MPU9250.

My question is:

  • How can I understand from the datasheet that the resolution in high frequency will be ok?
2

A few thoughts:

  • The MPU-9250 is an obsolete product, so it probably isn’t a good option for that reason alone.

  • The MPU-9250 incorporates low-pass filtering for the accelerometer data: the output data rate is not the same as the measurement bandwidth. Unfortunately, per page 9 of the datasheet this filter cannot be configured for higher than a 260 Hz corner frequency.

  • Products such as the ADCMXL3021BMLZ-ND are available which are specifically designed for machine condition monitoring, and incorporate useful built-in functionality for this purpose