Hi Jason,
Mechanical vibration noise sources operating nearby, such as speakers, motors, buttons may significantly increase the noise level. Electrical sources, such as a switched-mode power supply can also cause high frequency vibration.
Generally, accelerometers under test are typically powered using a battery rather than a DC power supply because the battery provides a clean DC voltage without coupling noise into the system.
The AN4077 recommends a 4.7uF ceramic capacitor at VDD to filter noise in case the input supply is noisy and a 0.1uF bypass capacitor at VDDIO to filter out high frequency noise.
Reducing the noise on the accelerometer output can be done by selecting the lowest possible ODR and using both Low Noise (LNOISE bit = 1) and High Resolution (MODS [1:0] = 0b10) modes. For more information please refer to our AN4075.
Best regards,
Tomas
PS: If my answer helps to solve your question, please mark it as "Correct". Thank you.
