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I'm working with a MEMS Accelerometer, specifically the MS 3028. In it, the sensitivity is given as the following:

enter image description here

That seems like exceptionally large variation in sensitivity. I am aware that this value varies with temperature and input voltage, but it is given that "All values are typical at +24°C, 80Hz and 5Vdc excitation unless otherwise stated", which per my understanding means a constant temperature and input voltage.

I do not understand whether there is a factor that I have missed that justifies this level of variation, or how to determine a "normal" value for my simulation of the 3028.

enter image description here

Please let me know if more information is required.

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Apparently a Wheatstone bridge in a MS 3028 accelerometer uses something called an Excitation Voltage. Read more about it in section one of this ti.com paper.

enter image description here

In the MS 3028 specification you linked to, several lines below the mV/g Sensitivity line you copied into the question, there is a line that specifies the excitation voltage range. As an example, the range for a 3028 which has a range of 2g (first column of the specification) is 2 Volts to 10 Volts.

In the MS 3028 specification, there is a foot not (foot note 1) next to the Sensitivity line in the table:

1 Output is ratiometric to excitation voltage

This website describes this as:

The actual output of these instruments is directly proportional, or ratiometric, to the excitation voltage. This means that if the excitation fluctuates, the output will change proportionally. As a result of this dependence on a steady excitation voltage, regulated power supplies are highly recommended.

Apparently, if the Excitation Voltage is regulated, the mV/g Sensitivity value will vary less.

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