MPL3115A2 accuracy clarification

[danielepaesani]

Hello, 

i would like some help to clarify the +- .4kPa absolute accuracy parameter in the MPL3115A2 data sheet: has this accuracy to be intended as an offset error which stays constant over the whole measurement range? I need to measure not an absolute pressure but pressure intervals over time, so, on reading P1 and P2, i wouldn't mind an offset  error, as long as it stays constant for both readings, cancelling itself out during the calculations. Conversely, a variable uncertainty (of  -.4 to + .4 kPa) on every reading wouldn't be acceptable. So, is the true pressure accuracy for differential readings the +-.05 kPa stated on the data sheet? Is the "pressure absolute accuracy" an offset error, constant over the rated pressure range? 

Thanks and best regards,

Daniele Paesani

PS I am aware that other sensor with different ranges/methods may seem to be better suited for this application.

[TomasVaverka · Accepted solution]

Hello Daniele,

Yes, the absolute pressure accuracy of ± 400 Pa is an offset error within the pressure range from 50 to 110 kPa and over the specified temperature range.

Take a closer look at chapter 6 of the AN4528 describing this in more detail.

Best regards,

Tomas