Microsystem for measuring audio PCB vibrations

It is well known, for electronic devices, that a high number of failures are due, all over the lifetime, to vibrations determined by their own operating regime. The purpose of this paper is to present a microsystem for audio processing dedicated to both the design and the validation phase of an electronic product related to the measuring of the acoustic emissions (unwanted vibrations in audio spectrum) generated by the main responsible phenomena: the piezoelectricity effect of the dielectric materials used for some MLCC capacitors and the magnetostriction effect of some magnetic materials used for inductors or transformers [1]. The proposed microsystem is based on an ARM Cortex-M7 microcontroller running at 600 MHz able to process the audio signals received from an acoustic array of MEMS digital microphones capturing the audio vibrations from all points of interest. Based on the processed signals, it is possible to check the efficiency of replacing the components responsible for the acoustic noise or necessity to change the design concept. Also, the microsystem can be used on a serial production line as an effective vibration analyzer to validate the vibration damping functionality solutions during the operating regime for a maximum accepted level of overall acoustic noise mentioned in product's requirements.