Gyroscope data of the LSM6DSV from the 2025 production batch exhibits abrupt bias changes

[JiaZiqing]

I have previously used a large quantity of LSM6DSV16XTR products from batch 426, and their data was completely normal. My device utilizes 16 gyroscopes simultaneously. Recently, I started using products from batch 509, and they have exhibited a peculiar phenomenon. Specifically, it includes two parts: (1) When the temperature slowly increases from -40°C to 85°C, observing the data of a gyroscope at rest, some gyroscopes show data jumps at certain temperature points (the jump temperature point varies for each gyroscope). For example, the data may jump from -0.98°/s to -0.08°/s. (2) For the same gyroscope, at the same temperature, the bias data varies significantly at different times. This phenomenon does not occur in every gyroscope, but it greatly troubles me because I cannot record and compensate for the bias data in the temperature chamber, as these biases have become highly irregular. This phenomenon did not occur in batch 426. Does anyone know why this is happening?

[Federica Bossi]

Hi @JiaZiqing ,

To understand better the phenomenon, can you please share some plots of what you have observed?

Thanks

[JiaZiqing]

Hi，Thank you for your reply.

The data in the four figures below are from four gyroscopes on the same PCB board tested in a temperature chamber. The board was placed stationary in the chamber, with the temperature gradually increased from -40℃ to 100℃.

It can be observed that the zero bias data of the first gyroscope is normal with continuous variation. However, the zero bias data of the other three gyroscopes showed abrupt jumps at different temperature points.

This experiment is repeatable: each individual gyroscope exhibited abrupt jumps near the same temperature points in every test, though the exact temperatures were not strictly identical.

[JiaZiqing]

I removed these gyroscopes with abnormal data and soldered them onto other PCBs for the test, and the abrupt jumps still occurred.