摘要 |
A Micro-Electro-Mechanical System closed-loop (MEMS) inertial device having a vertical comb drive that exhibits improved performance under vibration. The device includes one or more stator tines extending from a housing into a cavity formed by the housing. One or more rotor tines extend from a proof mass located in the cavity. The proof mass is joined to the housing by flexures which allow movement in the vertical direction. The rotor tines have a first length value in the direction of movement and the stator tines have a second length value in the direction of movement. The second length value is greater than the first length value. Also, the stator tines include two electrically separated portions. The lesser length of the rotor tines relative to the stator tines causes the attractive force between the rotor tines and either the upper or lower half of the stator tines to be relatively independent of rotor vertical position. This, in turn, produces better accelerometer accuracy in vibration environments.
|