AnsweredAssumed Answered

MPL3115A2 altitude variability

Question asked by miribelgart on Apr 3, 2016

Hi all,

 

We are using MPL3115A2 on a custom board to measure altitude differences between devices.

I have read all the Q&A I could find on this forum regarding issues with altitude measurement, but I am still not sure if what I am seeing is considered normal or not (using one-shot mode with 128 OSR, sampling at 1Hz):

 

1. The variability between consecutive samples (1 second apart) seems pretty big. The board is stationary, on a desk inside a small cardboard box to block out light. Within 5 minutes of sampling I get altitude between -6.1875m and -8.8125m, the average being -7.22m. There were no changes in the room during this time, no A/C or doors/windows opening or closing. Is this normal or is there a way to improve these results? Could this indicate a faulty sensor? Full log attached.

 

2. There seems to be a big difference between readings of different sensors: 3 sensors working simultaneously in the same conditions show averages of around -7m, 10.3m and 6m. Is this a matter of factory calibration that I should solve using OFF_H, or does this indicate that the sensors were harmed during soldering?

 

Thanks!

Miri

Original Attachment has been moved to: altitude.txt.zip

Outcomes