Unexpected step change in LPS25H Pressure

[lkoleszar]

Posted on November 04, 2015 at 15:37

I'm using the LPS25H pressure sensor and have noticed a strange stairstep behavior where one LPS25H seems to 

step or jump 10-20 Pa for several minutes to a few hours, then jumps back.  This behavior is quite different

from the normal RMS noise from sample to sample.  I first noticed this when running several sensors sitting on

the same desk over a weekend using the other sensors as a reference.  Note that step seems be some kind of fixed

offset since the relative pressure changes during the step does track with the other sensors.

I have also see nthis behavior when doing a temperature sweep.  In certain temperature bands the reading jumps 

out of the background atmospheric pressure trend, then snaps back when the temperature changes.  In particular

below 10C and a band around 20C.

Is this behavior expected?  I could expect some dift with temperature, but I would expect it to be more gradual.

- Luke

#lps25h

[Nickname3482_O]

Posted on November 09, 2015 at 12:19

Hello Luke,

0.1 to 0.2 mBar variations as in your description are expected from this class of devices, if you need better

performance from that point of view, I can suggest to use a newer generation of pressure sensors from ST such

as LPS22HB.

With Regards,

Adalberto