Yes, the IIS3DWB output data rate is nearly 27kHz and it would require frequent interactions from the MCU to read them out on the fly. For this reason the vibration sensor integrates 3kB FIFO buffer mainly for two purposes. First to avoid any data loss in case MCU would not be fast enough to react to read the data out from the output sensor registers and the second purpose is to limit intervention of the host processor with the sensor. The FIFO can be configured in many different functions and one of the most interesting for predictive maintenance applications is linked with interrupts. For example it is possible to program a FIFO filling threshold and to generate and interrupt to the MCU, when the FIFO stores exact amount of vibration sensor samples necessary for the MCU algorithms, like for RMS speed calculation to give an example. In other words, the MCU gets sensor interrupt only when exact amount of samples is ready in the FIFO.
