# US 11,029,176 B2 · System and method for vibration detection with no loss of position information using a magnetic field sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,176 B2 - Document ID: US11029176B2 - Status: Granted - Kind: B2 - Application number: 16/404,981 - Filed: 2019-05-07 - Published: 2020-11-12 - Granted: 2021-06-08 - Earliest claimed: 2019-05-07 - Assignees: Allegro MicroSystems, LLC - Applicants: Allegro MicroSystems, LLC - Inventors: Benjamin Geiger; Cédric Gillet - Web page: https://patentgrep.com/patent/US11029176B2 ## CPC - G01D 18/001: {Calibrating encoders} - G01D 5/147: {influenced by the movement of a third element, the position of Hall device and the source of magnetic field being fixed in respect to each other} - G01D 5/24476: {Signal processing (G01D5/2448 - G01D5/24495 take precedence)} - G01D 5/2448: {Correction of gain, threshold, offset or phase control} - G01D 5/2449: {using hard-stored calibration data} - G01D 5/2451: {Incremental encoders (G01D5/2454 takes precedence)} - G01P 3/487: delivered by rotating magnets - G01P 3/489: Digital circuits therefor - G01P 13/045: {with speed indication} - G01R 33/07: Hall effect devices - G01R 33/072: {Constructional adaptation of the sensor to specific applications} - G01R 33/09: Magnetoresistive devices - G01R 33/091: {Constructional adaptation of the sensor to specific applications} - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A method of detecting a vibration comprises determining a vibration flag has been set during a running mode, entering a vibration mode, providing direction information for a target object during the vibration mode of the magnetic field sensor, holding onto positive peak values and negative peak values of the magnetic field signal during the vibration mode of the magnetic field sensor, and returning to the running mode after receiving at least two clock cycles of the magnetic field signal with no further vibration flags set. ## Claims ### Claim 1 A method of detecting a vibration of a target object with a magnetic field sensor, the method comprising: generating one or more detector output signals having state transitions at times determined by applying a threshold to a magnetic field signal generated by one or more magnetic field sensing elements of the magnetic field sensor in response to a magnetic field affected by the target object; determining a vibration flag indicative of a vibration of the target object has been set during a running mode of the magnetic field sensor; entering a vibration mode of the magnetic field sensor when the vibration flag has been set; holding positive peak values and negative peak values of the magnetic field signal during the vibration mode of the magnetic field sensor; providing direction information for the target object during the vibration mode of the magnetic field sensor based on the one or more detector output signals; and returning to a running mode of the magnetic field sensor after a predetermined number of state transitions of the one or more detector output signals with no further vibration flags set. ### Claim 2 (depends on 1) The method of claim 1, wherein holding the positive peak values and the negative peak values comprises allowing outward updating of the positive peak values and the negative peak values while restricting inward updating of the positive peak values and the negative peak values during the vibration mode. ### Claim 3 (depends on 1) The method of claim 1, wherein the vibration flag comprises at least one of: an inflection flag, a peak in flag, a peak clamp flag, a phase too close flag, a direction change flag, a direction change peak flag, or a direction change running mode (rm) flag. ### Claim 4 (depends on 1) The method of claim 1, wherein an edge counter is incremented after each state transition of the one or more detector output signals. ### Claim 5 (depends on 4) The method of claim 4, wherein the positive peak values update on a rising edge of the state transitions of the one or more detector output signals. ### Claim 6 (depends on 4) The method of claim 4, wherein the negative peak values update on a falling edge of the state transitions of the one or more detector output signals. ### Claim 7 (depends on 4) The method of claim 4, wherein the determined vibration flag comprises a first vibration flag and wherein the edge counter is reset to zero if a second vibration flag indicative of a vibration of the target object is set. ### Claim 8 (depends on 1) The method of claim 1, wherein the threshold is based on the positive peak values and negative peak values. ### Claim 9 A method of detecting a vibration of a target object with a magnetic field sensor, the method comprising: generating one or more detector output signals having state transitions at times determined by applying a threshold to a magnetic field signal generated by one or more magnetic field sensing elements of the magnetic field sensor in response to a magnetic field affected by the target object; determining a vibration flag indicative of a vibration of the target object has been set during a running mode of a magnetic field sensor; entering a vibration mode in response to the vibration flag determination, wherein the vibration mode comprises providing direction information for the target object; and returning to the running mode of the magnetic field sensor after a predetermined number of state transitions of the one or more detector output signals with no vibration flags set. ### Claim 10 (depends on 9) The method of claim 9, wherein the vibration mode comprises holding positive peak values and negative peak values of the magnetic field signal. ### Claim 11 (depends on 10) The method of claim 10, wherein the vibration mode further comprises allowing inward updating of the positive peak values and the negative peak values while restricting outward updating of the positive and negative peak values. ### Claim 12 (depends on 9) The method of claim 9, wherein the vibration flag comprises at least one of: an inflection flag, a peak in flag, a peak clamp flag, a phase too close flag, a direction change flag, a direction change peak flag, or a direction change running mode (rm) flag. ### Claim 13 (depends on 9) The method of claim 9, wherein an edge counter is incremented after each state transition of the one or more detector output signals. ### Claim 14 (depends on 13) The method of claim 13, wherein the positive peak values update on the rising edge of the state transitions of the one or more detector output signals and the negative peak values update on the falling edge of the state transitions of the one or more detector output signals. ### Claim 15 A method of detecting vibration of a target object with a magnetic field sensor, the method comprising: generating one or more detector output signals having state transitions at times determined by applying a threshold to a magnetic field signal generated by one or more magnetic field sensing elements of the magnetic field sensor in response to a magnetic field affected by the target object; providing direction information for the target object during a vibration mode of a magnetic field sensor based on the one or more detector output signals; allowing outward updating of positive peak values and negative peak values of the magnetic field signal during the vibration mode while restricting inward updating of the positive peak values and the negative peak values; and generating the threshold based on the positive peak values and the negative peak values of the magnetic field signal. ### Claim 16 (depends on 15) The method of claim 15, further comprising entering the vibration mode based on a determination that a vibration flag indicative of a vibration of the target object has been set, wherein the vibration flag comprises at least one of: an inflection flag, a peak in flag, a peak clamp flag, a phase too close flag, a direction change flag, a direction change peak flag, or a direction change running mode (rm) flag. ### Claim 17 (depends on 15) The method of claim 15, wherein an edge counter is incremented after each state transition of the one or more detector output signals. ### Claim 18 (depends on 17) The method of claim 17, wherein the positive peak values update on a rising edge of the state transitions of the one or more detector output signals and the negative peak values update on a falling edge of the state transitions of the one or more detector output signals.