CIRCUIT AND METHOD FOR DYNAMIC OFFSET COMPENSATION IN A MEMS SENSOR DEVICE

摘要

An offset-compensation circuit in a MEMS sensor device, provided with a micromechanical detection structure that transduces a quantity to be detected into an electrical detection quantity, and with an electronic reading circuit, coupled to the micromechanical detection structure for processing the electrical detection quantity and supplying an output signal, which is a function of the quantity to be detected. A compensation structure is electrically coupled to the input of the electronic reading circuit and can be controlled for generating an electrical compensation quantity, of a trimmable value, for compensating an offset on the output signal; the compensation circuit has a control unit, which reads the output signal during operation of the MEMS sensor device; obtains information on the offset present on the output signal itself; and controls the compensation structure as a function of the offset information.

主权项

1. An offset-compensation circuit, comprising:
a control unit configured to control a compensation structure, to read an output signal during operation of a MEMS sensor , to obtain offset information about an offset present on the output signal; and to control the compensation structure as a function of the offset information; a low-pass filtering module coupled to the control unit and configured to generate a filtered output signal as a function of said output signal, the control unit is configured to obtain said offset information as a function of the filtered output signal; and a threshold-detector module, coupled to said low-pass filtering module, configured to receive said filtered output signal, and configured to perform a comparison between a value of said filtered output signal and at least one first threshold, and configured to generate a comparison signal, indicative of a result of the comparison, said control unit is configured to generate a control signal to control said compensation structure, as a function of said comparison signal.