LSM6DSL accelerometer sensitivity & offset changes with temperature

[Jolis Swann]

Posted on December 18, 2017 at 10:18

Hi everyone,

I am using the lsm6dsl mems. For my application, I need to calibrate the device in order to get the more precise values.

My calibration method is as follows :

- I measure the +/-1g in each axe

- I set the sensitivity with the full scale in LSB (from -1g to +1g)

- I set the offset by comparing the top value (+1g) and the bottom value (-1g) (for example if I get -1900 and +2100, I set the offset as -100)

My questions are :

- Is the calibration method correct?

- I observe big gaps with temperature changes (like 10 times the typical values given in the datasheet). Is it normal or there is something that I'm doing wrong?

- For temperature compensation, is it reliable to use typical values given in the datasheet or should I estimate it by measurment?

I hope my message is clear, sorry for my English.

Swann.

#calibration #lsm6dsl

[Miroslav BATEK]

Posted on December 19, 2017 at 20:11

Yes, I think this is the most simple calibration method for offset compensation.

You can also check design tip

http://www.st.com/content/ccc/resource/technical/document/design_tip/group0/28/fa/7d/ed/6a/41/4f/c1/DM00253745/files/DM00253745.pdf/jcr:content/translations/en.DM00253745.pdf

 for some more theory.

We also offer read-time accelerometer calibration library (MotionAC) and 6-point calibration procedure (in MotionTL). All libraries with examples can be found in

http://www.st.com/content/st_com/en/products/embedded-software/mcus-embedded-software/stm32-embedded-software/stm32cube-expansion-packages/x-cube-mems1.html

software package.

Concerning the temperature dependency can you please specify what exactly change with the temperature? If you can provide some more data it would be helpful.

I would not rely on typical value, because each sensor can be slightly different.

May I know what will be the target application?