False triggering prevention in a resonant phase sensing system

Patent metadata

Field	Value
Publication number	US-11204670-B2
Application number	US-202117142484-A
Country	US
Kind code	B2
Filing date	Jan 6, 2021
Priority date	Mar 29, 2018
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

A system may include a resistive-inductive-capacitive sensor, a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to at a plurality of periodic intervals, measure phase information associated with the resistive-inductive-capacitive sensor and based on the phase information, determine a displacement of a mechanical member relative to the resistive-inductive-capacitive sensor. The system may also include a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency and a driving amplitude, wherein at least one of the driving frequency and the driving amplitude varies among the plurality of periodic intervals.

First claim

What is claimed is:

1. A system comprising:
a resistive-inductive-capacitive sensor; and
a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to:
at a plurality of periodic intervals, measure phase information associated with the resistive-inductive-capacitive sensor; and
based on the phase information, determine a displacement of a mechanical member relative to the resistive-inductive-capacitive sensor.

2. The system of claim 1 , wherein the measurement circuit is further configured to determine an occurrence of a physical interaction associated with a human-machine interface associated with the mechanical member based on the phase information.

3. The system of claim 2 , further comprising a processing circuit configured to process the phase information and data from at least one other sensor to determine the occurrence of the physical interaction.

4. The system of claim 3 , wherein the at least one other sensor comprises one or more of an accelerometer, a gyroscope, a touch sensor, a proximity sensor, a temperature sensor, and an ambient light sensor.

5. The system of claim 1 , wherein the measurement circuit comprises a coherent incident/quadrature detector to track a resonant frequency of the resistive-inductive-capacitive sensor and the measurement circuit is configured to measure the phase information using the coherent incident/quadrature detector.

6. A method comprising:
at a plurality of periodic intervals, measure phase information associated with a resistive-inductive-capacitive sensor; and
based on the phase information, determine a displacement of a mechanical member relative to the resistive-inductive-capacitive sensor.

7. The method of claim 6 , further comprising determining an occurrence of a physical interaction associated with a human-machine interface associated with the mechanical member based on the phase information.

8. The method of claim 7 , further comprising processing the phase information and data from at least one other sensor to determine the occurrence of the physical interaction.

9. The method of claim 8 , wherein the at least one other sensor comprises one or more of an accelerometer, a gyroscope, a touch sensor, a proximity sensor, a temperature sensor, and an ambient light sensor.

10. The method of claim 6 , further comprising tracking a resonant frequency of the resistive-inductive-capacitive sensor wherein the phase information is measured using a coherent incident/quadrature detector.

Assignees

• Cirrus Logic Int Semiconductor Ltd
• Cirrus Logic Inc

Inventors

• Maru Siddharth
• Das Tejasvi
• Lapointe Luke
• Marijanovic Srdjan
• You Zhong
• Kinney Drew
• Doy Anthony S
• King Eric J

Classifications

• G01D5/2026 Primary

  constituting a short-circuiting element · CPC title

• G01D5/243

  influencing the phase or frequency of AC · CPC title

• G06F3/045

  using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/044 Primary

  by capacitive means · CPC title