Inertial sensor
View Patent ↗An inertial sensor, comprises a detection element detecting an amount of a physical quantity in a detection axis direction, a plurality of support members having flexibility and supporting nearly a center of the detection element, and a package substrate housing the detection element and the plurality of support members. In a case when an X-axis is defined as an extending direction of the plurality of support members, a Y-axis is perpendicular to the X-axis in a plane including the detection element, and a Z-axis is perpendicular to the X-axis and the Y-axis, one of load components in a direction of the Y-axis of the detection member applied to the plurality of support members is nearly equal to other among the plurality of support members, and one of load components in a direction of the Z-axis is nearly equal to the other among the plurality of support members.
1. An inertial sensor, comprising:
a detection element detecting an amount of a physical quantity in a detection axis direction;
a plurality of support members having flexibility and supporting nearly a center of the detection element, the plurality of support members each including first and second ends;
a package substrate, mounted at an angle θ with respect to the vertical axis, housing the detection element and the plurality of support members; and
a substrate including an opening portion formed therein, the first end of the plurality of support members connected at a lower surface of the substrate, the second end of the plurality of support members extending through the opening portion of the substrate above an upper surface of the substrate,
wherein in a case when an X-axis is defined as an extending direction of the detection element, a Y-axis is perpendicular to the X-axis, and a Z-axis is perpendicular to the X-axis and the Y-axis, at least two of the support members are disposed symmetrically with respect to the Y-axis through the center of the detection element,
wherein the detection element has a detection axis that detects an angular velocity and coincides with a direction of Z-axis that makes the angle of θ with respect to a vertical direction, and a resulting combined load of a load component in a direction of Y-axis and a load component in the direction of Z-axis includes a load component based on gravity acceleration,
one of load components of the detection element in the direction of Y-axis applied to the support members disposed symmetrically with respect to the Y-axis through the center of the detection element is nearly equal to other load applied to the symmetrical support members at the other side of the Y-axis through the center of the detection element, and
one of load components of the detection element in the direction of Z-axis applied to the support members disposed symmetrically with respect to the Y-axis through the center of the detection element is nearly equal to other load applied to the symmetrical support members at the other side of the Y-axis through the center of the detection element.
2. The inertial sensor according to claim 1 , wherein the Z-axis makes the angle of θ with respect to the vertical direction by tilting the inertial sensor around a longitudinal direction of the sensor.
3. An inertial sensor device, comprising:
the inertial sensor according to claim 1 ;
a plurality of lead terminals electrically coupled to the inertial sensor; and
a molded package including the inertial sensor.
4. The inertial sensor device according to claim 3 , wherein the molded package includes a first lead terminal extending toward a direction of a bottom surface of the molded package from a first side of the molded package, and a second lead terminal longer than the first lead terminal, the second lead terminal extending toward the direction of the bottom surface of the molded package from a second side opposite the first side, and the second lead terminal includes a plurality of bending parts adjacent the molded package.