Anchor tracking for MEMS accelerometers
First Claim
1. A micro electro-mechanical system (MEMS) accelerometer, comprising:
- at least one anchor coupled to a substrate;
a proof mass connected to the at least one anchor; and
a counter-balance mass connected to the proof mass and to the at least one anchor,wherein, in response to an acceleration of the MEMS accelerometer in a first direction, the proof mass is configured to move in the first direction and the counter-balance mass is configured to move in a second direction opposite from the first direction, andwherein, in response to displacement of the at least one anchor in the first direction, the proof mass and the counter-balance mass are configured to move in the first direction.
1 Assignment
0 Petitions
Accused Products
Abstract
A microelectromechanical system (MEMS) accelerometer is described. The MEMS accelerometer is arranged to limit distortions in the detection signal caused by displacement of the anchor(s) connecting the MEMS accelerometer to the underlying substrate. The MEMS accelerometer may include masses arranged to move in opposite directions in response to an acceleration of the MEMS accelerometer, and to move in the same direction in response to displacement of the anchor(s). The masses may, for example, be hingedly coupled to a beam in a teeter-totter configuration. Motion of the masses in response to acceleration and anchor displacement may be detected using capacitive sensors.
-
Citations
20 Claims
-
1. A micro electro-mechanical system (MEMS) accelerometer, comprising:
-
at least one anchor coupled to a substrate; a proof mass connected to the at least one anchor; and a counter-balance mass connected to the proof mass and to the at least one anchor, wherein, in response to an acceleration of the MEMS accelerometer in a first direction, the proof mass is configured to move in the first direction and the counter-balance mass is configured to move in a second direction opposite from the first direction, and wherein, in response to displacement of the at least one anchor in the first direction, the proof mass and the counter-balance mass are configured to move in the first direction. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A micro electro-mechanical system (MEMS) accelerometer, comprising:
-
at least one anchor coupled to a substrate; a beam movably coupled to the at least one anchor; a proof mass coupled to the beam and a counter-balance mass coupled to the beam; and a first electrode and a second electrode, the first and second electrodes being coupled to the substrate, wherein the proof mass forms a first capacitive sensor with the first electrode and the counter-balance mass forms a second capacitive sensor with the second electrode. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
-
17. A method for detecting acceleration using a micro electro-mechanical system (MEMS) accelerometer, the method comprising:
-
sensing motion of a proof mass in a first direction in response to acceleration of the MEMS accelerometer to obtain a first detection signal, the proof mass being coupled to at least one anchor; sensing motion of a counter-balance mass in a direction that is opposite from the first direction in response to the acceleration of the MEMS accelerometer to obtain a second detection signal, the counter-balance mass being coupled to the at least one anchor; sensing motion of the proof mass in a second direction in response to displacement of the at least one anchor to obtain a third detection signal; sensing motion of the counter-balance mass in the second direction in response to the displacement of the at least one anchor to obtain a fourth detection signal; and detecting the acceleration of the MEMS accelerometer using the first, second, third and fourth detection signals. - View Dependent Claims (18, 19, 20)
-
Specification