BMP390 Wrong values

[Lucio]

Hello everyone,

I've just switched from a BMP280 to a BMP390 in my drone prototype. Everything was working fine with the BMP280 but I wanted more precision and so I bought the 390. Adapted the Arduino code (I'm using the Adafruit_BMP3xx library) and managed to get everything working with the given example. During my tests I noticed that, every time I start a measurement session, the first measure is wrong...how can this be possible???

Those are the filtering options I'm using:

Temperature Oversampling: 2X

Pressure Oversampling: 32X

IIR Coefficient: 3

Output data rate: 100 Hz

I tried using standard settings from the datasheet but that gives the same problem either.

EDIT: I also noticed that the measures are less precise than the ones taken with the BMP280, how is this possible since the 390 is more precise?

Any thoughts about this issue?

Bye,

Lucio

[BSTRobin]

Hi Lucio,

You can refer the following software and sensor setting for your application.
Software example code: https://github.com/boschsensortec/BMP3-Sensor-API/tree/master/examples
Sensor setting for drone application:

[Lucio]

Hi Robin,

thanks for the informations provided!

I just tried to apply the settings you sent and the datas seems a little more stable but I still cannot get the declared 25cm accuracy...any ideas why? (just to be clear, the BMP280 seemed more precise and stable😬)

Thanks for your help,

Lucio

[BSTRobin]

Hi Lucio,

How do you test BMP390 and BMP280 relative accuracy?

[Lucio]

Hi Robin,
my Arduino code outputs altitude data every half second. Those data, when compared, results way more noisy if measured with the BMP390.