Dear Sensortec Team,
we use BMI270 for our mini drones in series production. From a recent batch however, a few drones (around 5%) show weird flight behavior. After inspecting the flight log, we figure out that the Z-axis gyro signal of the "faulty" drones has significant DC bias and higher noise content in comparison to the "healthy" drones, which led to deviations in yaw estimation.
We are aware that mechanical strain on the IMU can lead to abnormal gyro sensing. The layout of the PCB has been designed following this guideline "https://www.bosch-sensortec.com/media/boschsensortec/downloads/handling_soldering_mounting_instructions/bst-mis-hs000.pdf" (e.g. off-center of strain line, no vias under the chip). Also soldering process was configured according to it.
Any idea about what can be the reason? Is there any extra advice that we should pay attention to?
Please let me know if you need more context.
Thanks,
Min