Readout system for MEMs-based capacitive accelerometers and strain sensors, and method for reading

摘要

The invention relates to a method and an electronic readout circuit (50) for measuring a capacitance of a MEMs sensor (90), the readout circuit comprising: an input stage (10) for receiving a first signal (14) from the sensor and for presenting a second signal (17); a charge amplifier stage (20) for amplifying and integrating the second signal; control logic (70) for controlling the readout circuit according to a predefined timing relation synchronized to actuation voltages (51, 52) applied to the sensor for generating the first signal; the readout circuit further comprising: a first switching means (12) for applying a first reference voltage to the sensor; a second switching means (16) for applying the second signal to the charge amplifier stage; the first and the second switching means (12, 16) being controlled according to the predefined timing relation such that a plurality of the second signals are accumulated.