We are currently working with the LIS2HH12TR accelerometer on our Smarttrak board, using an STM32U575VIT6Q as the main MCU, and are facing an issue with unstable sensor readings.
Communication appears to be functioning correctly, we verified the I2C clock waveform and confirmed that the bus is operating at 100 kHz. The accelerometer responds properly, and we are able to read data successfully. However, the measured values are not stable.
For example, the calculated angle values normally stay around 20–30 degrees, but occasionally they suddenly jump to 70–80 degrees without any actual movement. These abrupt spikes are causing instability in our application and affecting overall board operation.
An additional challenge is that this behavior appears randomly and in 1 out of 5 devices, making it difficult for us to trace the exact source of the issue.
We would appreciate any guidance on possible causes and recommended debugging steps. Specifically, we would like to understand:
What could cause sudden spikes or abnormal accelerometer readings?
Could this be related to I2C timing, noise, grounding, PCB layout, or sensor configuration?
Are there specific STM32 side precautions or best practices for reliable accelerometer data acquisition with the LIS2HH12TR?
Any suggestions or troubleshooting advice would be greatly appreciated.
