ADXL343 Tilt angle limit

Hi Saurabh, 

The ADXL343  typical 0g offset is +/-35mg. Converting this offset to angle: asin(35mg) = 2 degree. Also, if you look at figure 4 of the datasheet (0g offset distribution), 0g offset can be in the 100mg order, which is equivalent to ~5.7 degree. So your observation makes sense and unfortunately, offset calibration is the only option to reduce the angle error for near 0 degree tilt. The good news is that calibration can be done once during production and the initial offset can be stored in an external memory.

If calibration is not an option I recommend looking into high performance devices such as ADXL355, that has a tighter 0g offset distribution and much better resolution and noise performance. 

I hope this helps, 

Pablo. 

Hi Pablo,

Thank you for your suggestions. Calibration at production site is quite a feasible option. We'll surely evaluate it.

Regards,
Saurabh

Hi Saurabh, 

great to hear that! let me know if there is anything else I can help with. 

regards, 

Pablo. 

Hi Pablo,

That's it, thanks for your help.

Regards

Hi Pablo,

Sorry to trouble you again. I've gone through offset calibration methods mentioned in the datasheet. Could you please suggest any application note or literature on the forum, that provides pointers about production-line calibration procedure? Thanks.

Regards,
Saurabh

Hi Saurabh, 

I am not aware of any production-line specific recommendation document. But you can take a look at AN-1057: Using an Accelerometer for Inclination Sensing | Analog Devices

it has very useful information about tilt sensing and the last section describes the calibration equation. 

Regards, 

Pablo. 

Thank you Pablo, the link has valuable information.

Thank you Pablo, the link has valuable information.