INERTIAL MEASUREMENT CIRCUIT, CORRESPONDING DEVICE AND METHOD

A circuit (10) comprises an inertial measurement unit such as a MEMS gyroscope (12) configured to be oscillated via a driving signal (D+, D-, Dsq) produced by driving circuitry (14A, 14B, 16, 18, 20A, 20B, 22, 24, 26, 28, 30, 32) and a lock-in amplifier, LIA (38) receiving a sensing signal (S+, S-, Ssq) from the inertial measurement unit (12) as well as a reference demodulation signal which is a function of the driving signal (D+, D-, Dsq). The LIA amplifier (38) is configured to produce an inertial measurement signal (Vout) based on the sensing signal (S+, S-, Ssq) from the inertial measurement unit (12) and the reference demodulation signal, wherein the reference demodulation signal is affected by a variable phase error. Phase meter circuitry (40) configured to receive the driving signal (D+, D-, Dsq) and the sensing signal (S+, S-, Ssq) produces, as a function of the phase difference (ΔΦds) between the driving signal (D+, D-, Dsq) and the sensing signal (S+, S-, Ssq), a phase correction signal. The phase correction signal is applied (56) to the reference demodulation signal of the lock-in amplifier (38). In response to the phase correction signal being applied (56) to the reference demodulation signal of the lock-in amplifier (38) the phase error is maintained in the in the vicinity of a reference value (Φer0), thus minimizing the effects of the variation of the phase error.