# US 10,119,834 B2 · MEMS sensor with voltage sensing of movable mass > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,119,834 B2 - Document ID: US10119834B2 - Status: Granted - Kind: B2 - Application number: 15/258,939 - Filed: 2016-09-07 - Published: 2017-06-15 - Granted: 2018-11-06 - Earliest claimed: 2015-12-10 - Assignees: Panasonic Corporation - Applicants: Panasonic Corporation - Inventors: Adolfo Giambastiani; Jaakko Ruohio - Web page: https://patentgrep.com/patent/US10119834B2 ## CPC - G01C 25/00: Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass (testing, calibrating or compensating compasses G01C17/38) - B81B 3/0021: {Transducers for transforming electrical into mechanical energy or vice versa (dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00)} - G01C 19/5712: the devices involving a micromechanical structure - G01C 19/5726: Signal processing - G01C 25/005: {initial alignment, calibration or starting-up of inertial devices} - B81B 2201/0242: Gyroscopes - B81B 2203/0109: Bridges - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00) ## Abstract A suspended spring-mass system is suspended from a plurality of the anchoring points. A source voltage is provided from one of anchoring points to the suspended spring-mass system. The other anchoring points have measurement nodes which measure the voltage at those anchoring points. If a voltage other than the source voltage is received at one of the measurement nodes, an error is identified. ## Claims ### Claim 1 A microelectromechanical sensor, comprising: a plurality of anchoring points; a suspended spring-mass system, comprising: a plurality of movable masses; a plurality of springs coupling the plurality of movable masses to each other and to suspend the plurality of movable masses from the plurality of anchoring points, wherein the plurality of moving masses and the plurality of anchoring points are electrically connected by the plurality of springs; a first voltage source coupled to apply a system voltage level to the suspended spring-mass system via a first anchoring point of the plurality of anchoring points; a measurement node coupled to a second anchoring point of the plurality of anchoring points to measure a voltage of the second anchoring point; and processing circuitry configured to identify an error of the suspended spring-mass system based on the measured voltage. ### Claim 2 (depends on 1) The microelectromechanical sensor of claim 1, wherein the measured voltage comprises a first measured voltage, further comprising an additional measurement node coupled to measure a second measured voltage via a third anchoring point of the plurality of anchoring points, wherein the processing circuitry is further configured to identify the error of the suspended spring-mass system based on the second measured voltage. ### Claim 3 (depends on 2) The microelectromechanical sensor of claim 2, wherein the error comprises one or more damaged components of the suspended spring-mass system, and wherein the processing circuitry is further configured to identify a first subset of possible damaged components of the suspended spring-mass system based on the first measured voltage, and to identify a second subset of possible damaged components of the suspended spring-mass system based on the second measured voltage. ### Claim 4 (depends on 3) The microelectromechanical sensor of claim 3, wherein the processing circuitry is configured to identify the first subset of possible damaged components when the first measured voltage differs from the system voltage level by more than an error threshold voltage and the second measured voltage is within the error threshold voltage of the system voltage level, and to identify the second subset of possible damaged components when the second measured voltage differs from the system voltage level by more than the error threshold voltage and the first measured voltage is within the error threshold voltage of the system voltage level. ### Claim 5 (depends on 4) The microelectromechanical sensor of claim 4, wherein the error threshold voltage is based on a percentage change from the system voltage level. ### Claim 6 (depends on 2) The microelectromechanical sensor of claim 2, wherein the processing circuitry is further configured to take a first corrective action if the error is identified based on the first measured voltage and to take a second corrective action if the error is based on the second measured voltage. ### Claim 7 (depends on 6) The microelectromechanical sensor of claim 6, wherein the first corrective action comprises the processing circuitry being further configured to disable the microelectromechanical sensor, and wherein the second corrective action comprises the processing circuitry being further configured to modify the operation of the microelectromechanical sensor. ### Claim 8 (depends on 7) The microelectromechanical sensor of claim 7, wherein the modification of the operation of the microelectromechanical sensor comprises a modification of a sense scaling factor of the processing circuitry or a modification of a drive voltage applied to one of the plurality of movable masses. ### Claim 9 (depends on 1) The microelectromechanical sensor of claim 1, wherein the processing circuitry is configured to identify the error of the suspended spring-mass system based on a difference between the measured voltage and the system voltage level. ### Claim 10 (depends on 1) The microelectromechanical sensor of claim 1, wherein the voltage source applies the system voltage level from the first anchoring point to the suspended spring-mass system via a first spring of the plurality of springs, and wherein the first spring of the plurality of springs is located in series between the first anchoring point and the other components of the suspended spring-mass system. ### Claim 11 (depends on 10) The microelectromechanical sensor of claim 10, wherein the measurement node receives the measured voltage via a second spring of the plurality of springs and the second anchoring point, and wherein the second spring is located in series between the first anchoring point and the second anchoring point. ### Claim 12 (depends on 1) The microelectromechanical sensor of claim 1, wherein the measured voltage comprises a second measured voltage and wherein the measurement node comprises a second measurement node, further comprising: a second voltage source coupled to apply the system voltage level to the suspended spring-mass system via the second anchoring point; a first measurement node coupled to the first anchoring point to measure a first measured voltage of the first anchoring point; a first switch coupled to the first anchoring point to selectively couple the first anchoring point to the first voltage source or to the first measurement node; and a second switch coupled to the second anchoring point to selectively couple the second anchoring point to the second voltage source or the second measurement node. ### Claim 13 (depends on 12) The microelectromechanical sensor of claim 12, wherein the processing circuitry is further configured to cause one of the first switch or the second switch to provide the system voltage level to the suspended spring-mass system and to cause the other of the first switch or the second switch to couple the first anchoring point to the first measurement node or to couple the second anchoring point to the second measurement node, and to identify the error of the suspended spring-mass system based on a comparison of the system voltage level to the first measured voltage or the second measured voltage associated with the other of the first switch or the second switch. ### Claim 14 (depends on 12) The microelectromechanical sensor of claim 12, further comprising: a third voltage source coupled to apply the system voltage level to the suspended spring-mass system from a third anchoring point; a third measurement node coupled to measure a third measured voltage via the third anchoring point; and a third switch coupled to the third anchoring point to selectively couple the third anchoring point to the third voltage source or the third measurement node. ### Claim 15 (depends on 14) The microelectromechanical sensor of claim 14, wherein the processing circuitry is further configured to cause the first switch to couple the first voltage source to provide the system voltage level to the suspended spring-mass system, to cause the second switch to couple the second anchoring point to the second measurement node to measure the second measured voltage, to cause the third switch to couple the third anchoring point to the third measurement node to measure the third measured voltage, and to identify an initial error of the suspended spring-mass system based on the second measured voltage and the third measured voltage. ### Claim 16 (depends on 15) The microelectromechanical sensor of claim 15, wherein the processing circuitry is further configured to cause the second switch to couple the second voltage source to provide the system voltage level to the suspended spring-mass system, to cause the first switch to couple the first anchoring point to the first measurement node to measure the first measured voltage, to cause the third switch to couple the third anchoring point to the third measurement node to measure a new third measured voltage, and to identify a refined error of the suspended spring-mass system based on the initial error, the first measured voltage, and the new third measured voltage. ### Claim 17 (depends on 16) The microelectromechanical sensor of claim 16, wherein the processing circuitry is further configured to cause the third switch to couple the third voltage source to provide the system voltage level to the suspended spring-mass system, to cause the first switch to couple the first anchoring point to the first measurement node to measure a new first measured voltage, to cause the second switch to couple the second anchoring point to the second measurement node to measure a new second measured voltage, and to identify a further refined error based on the refined error, the initial error, the new first measured voltage, and the new second measured voltage. ### Claim 18 A method for identifying an error within a microelectromechanical sensor, the method comprising: providing, from a first voltage source, a system voltage to a first anchoring point of a plurality of anchoring points; applying, via the first anchoring point, a system voltage level to a suspended spring-mass system; receiving, at a second anchoring point of the plurality of anchoring points, a received voltage via the suspended spring-mass system; providing the received voltage from the second anchoring point to a measurement node; and identifying, by processing circuitry, an error of the suspended spring-mass system based on the received voltage at the measurement node. ### Claim 19 A microelectromechanical sensor, comprising: a plurality of anchoring points; a plurality of source/sense circuits, wherein each of the source sense circuits is coupled to one of the plurality of anchoring points, each source/sense circuit comprising: a voltage source; a measurement node; and a switch; a suspended spring-mass system suspended from the plurality of anchoring points; and processing circuitry configured to cause a first source/sense circuit to couple the voltage source of the first source/sense circuit to a first anchoring point of the plurality of anchoring points, to cause a second source/sense circuit couple a second anchoring point of the plurality of anchoring points to the measurement node of the second source/sense circuit, and to identify an error of the suspended spring-mass system based on a voltage received at the second measurement node.