Patent ID: 7555949
Filing Date: 2009-07-07
Classification: G01C

Abstract:
1. An angular velocity measuring device comprising: a substrate; an angular velocity detection element having a vibrating body disposed in the substrate so as to be vibrated in first and second axial directions out of three axial directions corresponding to three axes disposed at right angles to each other, a driving element arranged to vibrate the vibrating body in the first axial direction using a drive signal, and a displacement detecting element arranged to detect displacement in the second axial direction of the vibrating body and output a detection signal when an angular velocity is applied around the third axis while the vibrating body is vibrated in the first axial direction; drive wiring disposed in the substrate and connected to the driving element of the angular velocity detection element; detection wiring disposed in the substrate and connected to the displacement detecting element of the angular velocity detection element; and a signal processing element disposed in the substrate and connected to the drive wiring and the detection wiring; wherein the substrate is a multilayer substrate including a plurality of insulation layers; the detection wiring is disposed between two of the plurality of insulation layers inside the multilayer substrate; low-impedance wiring facing the detection wiring is disposed at a location different from the detection wiring in the thickness direction of the multilayer substrate therein; the angular velocity detection element includes an element-side drive electrode connected to the driving element, an element-side detection electrode connected to the displacement detecting element, and an element-side low-impedance electrode located between the element-side drive electrode and the element-side detection electrode arranged to cut off the coupling between the element-side drive electrode and the element-side detection electrode located on a mounting surface side of the multilayer substrate; on the top surface of the multilayer substrate, a substrate-side drive electrode connected to the drive wiring and facing the element-side drive electrode, a substrate-side detection electrode connected to the detection wiring and facing the element-side detection electrode, and a substrate-side low-impedance electrode positioned between the substrate-side drive electrode and the substrate-side detection electrode arranged to cut off the coupling between the substrate-side drive electrode and the substrate-side detection electrode are provided; the angular velocity detection element is mounted on a top surface of the multilayer substrate via metal bumps; the element-side drive electrode and the substrate-side drive electrode are connected via metal bumps; the element-side detection electrode and the substrate-side detection electrode are connected via metal bumps; the element-side low-impedance electrode and the substrate-side low-impedance electrode are connected at a low-impedance reference potential; and the element-side low-impedance electrode and the substrate-side low-impedance electrode are arranged to at least partially face each other.