Modeling of a three-axes MEMS gyroscope with feedforward PI quadrature compensation

The present paper is focused on the theoretical and experimental analysis of a three-axes MEMS gyroscope, developed by ST Microelectronics, implementing an innovative feedforward PI quadrature compensation architecture. The gyro-scopes structure is explained and equations of motion are written; modal shapes and frequencies are obtained by finite element simulations. Electrostatic quadrature compensation strategy is explained focusing on the design of quadrature cancellation electrodes. A new quadrature compensation strategy based on feedforward PI architecture is introduced in this device to take into account variations of device parameters during lifetime. Obtained results show a significant reduction of the quadrature error resulting in a improved performance of the device. Fabrication and test results conclude the work.