Signal processing for MEMS capacitive transducers

摘要

This application relates to circuitry for processing sense signals generated by MEMS capacitive transducers for compensating for distortion in such sense signals. The circuitry has a signal path between an input (204) for receiving the sense signal and an output (205) for outputting an output signal based on said sense signal. Compensation circuitry (206, 207) is configured to monitor the signal at a first point along the signal path and generate a correction signal (Scorr); and modify the signal at at least a second point along said signal path based on said correction signal. The correction signal is generated as a function of the value of the signal at the first point along the signal path so as to introduce compensation components into the output signal that compensate for distortion components in the sense signal. The first point in the signal path may be before or after the second point in the signal path. The monitoring may be performed in an analogue or a digital part of the signal path and in either case the modification may be applied in an analogue or a digital part of the signal path.