公开(公告)号：EP4170356A1

公开(公告)日：2023-04-26

申请号：EP22200494.7

申请日：2022-10-10

Applicant: STMicroelectronics S.r.l. ,  STMicroelectronics Inc.

Inventor： GARBARINO, Marco ,  CHOI, Davy ,  RIZZINI, Francesco ,  HU, Yamu

IPC: G01P21/00 ,  G01P15/125 ,  G01P15/18 ,  G01P15/08

Abstract: A microelectromechanical system (MEMS) accelerometer sensor (12x, 12y, 12z) has a mobile mass and a sensing capacitor. To self-test the sensor, a test signal having a variably controlled excitation voltage and a fixed pulse width is applied to the sensing capacitor. The leading and trailing edges of the test signal are aligned to coincide with reset phases of a sensing circuit (32-36) coupled to the sensing capacitor. The variably controlled excitation voltage of the test signal is configured to cause an electrostatic force which produces a desired physical displacement of the mobile mass. During a read phase of the sensing circuit, a variation in capacitance of sensing capacitor due to the actual physical displacement of the mobile mass is sensed for comparison to the desired physical displacement.