公开(公告)号：EP4098973A1

公开(公告)日：2022-12-07

申请号：EP22174570.6

申请日：2022-05-20

Applicant: STMicroelectronics S.r.l.

Inventor： LANGFELDER, Giacomo ,  GAFFURI PAGANI, Leonardo ,  GUERINONI, Luca ,  FALORNI, Luca Giuseppe ,  FEDELI, Patrick ,  CARULLI, Paola

IPC: G01C19/5776

Abstract: 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.