Abstract: A system may include a plurality of sensors configured to sense a physical quantity and a calibration subsystem configured to perform a calibration comprising: comparing a measured characteristic from each of at least two sensors of the plurality of sensors to determine a sensitivity drift of at least one sensor of the plurality of sensors; based on the measured characteristics of the at least two sensors and stored reference characteristics for the at least two sensors, calculating a normalization factor; and applying the normalization factor to the measured characteristic of the at least one sensor to ensure sensitivity of the plurality of sensors relative to each other remains approximately constant.

Abstract: A method may include, when in a low-power mode of a power converter, monitoring an output voltage of the power converter; comparing, with a single comparator, the output voltage to a first threshold voltage and cause the power converter to enter a magnetization phase of the low-power mode responsive to the output voltage falling below the first threshold voltage; and during the magnetization phase and a demagnetization phase of the low-power mode, comparing, with the single comparator, the output voltage to a second threshold voltage lower than the first threshold voltage and cause the power converter to enter the high-power mode responsive to the output voltage falling below the second threshold voltage.

Abstract: A system may include amplifier circuitry configured to drive an electromagnetic load with a driving signal and a processing system communicatively coupled to the electromagnetic load and configured to compensate for current-sensing error of the processing system caused by feedback circuitry of the amplifier circuitry.

Abstract: A system may include a resistive-inductive-capacitive sensor, a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor, and a filter communicatively coupled to the measurement circuit. The measurement circuit may be configured to 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 filter may be configured to isolate changes to the displacement which are significantly slower than an expected change to the displacement in response to a human interaction with the mechanical member.

Abstract: The present disclosure relates to circuitry for driving a load. The circuitry comprises: primary driver circuitry coupled to a primary signal path and operable to drive the load with a playback signal in a first mode of operation of the circuitry, wherein a playback signal comprises a signal that drives the load to generate a desired output; auxiliary driver circuitry coupled to an auxiliary signal path; an auxiliary current sense resistor in the auxiliary signal path; and current detection circuitry coupled to the auxiliary current sense resistor and configured to generate a signal indicative of a current through the load. One of the primary driver circuitry and the auxiliary driver circuitry is operable to drive the load with a pilot signal in a second mode of operation of the circuitry, wherein a pilot signal comprises a signal having a predefined frequency or frequency content and a predefined magnitude.

Abstract: The controller for a system including a power converter may be configured to cause the system to operate in one of a low-power mode and the high-power mode based on power demand from a load at the output of the power converter and when in the low-power mode, monitor the output of the power converter to detect an occurrence of a load transient from the load and in response to detecting the occurrence of the load transient, transition from the low-power mode to the high-power mode via a transition mode to minimize undershoot and overshoot of the output voltage.

Abstract: The controller for a system including a power converter may be configured to cause the system to operate in one of a low-power mode and the high-power mode based on power demand from a load at the output of the power converter and when in the low-power mode, monitor the output of the power converter to detect an occurrence of a load transient from the load and in response to detecting the occurrence of the load transient, transition from the low-power mode to the high-power mode via a transition mode to minimize undershoot and overshoot of the output voltage.

Abstract: A system may include a resonant sensor configured to sense a physical quantity, a measurement circuit communicatively coupled to the resonant sensor and configured to measure one or more resonance parameters associated with the resonant sensor and indicative of the physical quantity using an incident/quadrature detector having an incident channel and a quadrature channel and perform a calibration of a non-ideality between the incident channel and the quadrature channel of the system, the calibration comprising determining the non-ideality by controlling the sensor signal, an oscillation signal for the incident channel, and an oscillation signal for the quadrature channel; and correcting for the non-ideality.

Abstract: A force sensing system for determining if a user input has occurred, the system comprising: an input channel, to receive an input from at least one force sensor; an activity detection stage, to monitor an activity level of the input from the at least one force sensor and, responsive to an activity level which may be indicative of a user input being reached, to generate an indication that an activity has occurred at the force sensor; and an event detection stage to receive said indication, and to determine if a user input has occurred based on the received input from the at least one force sensor.

Abstract: The present disclosure relates to circuitry for driving a load. The circuitry comprises: primary driver circuitry coupled to a primary signal path and operable to drive the load with a playback signal in a first mode of operation of the circuitry, wherein a playback signal comprises a signal that drives the load to generate a desired output; auxiliary driver circuitry coupled to an auxiliary signal path; an auxiliary current sense resistor in the auxiliary signal path; and current detection circuitry coupled to the auxiliary current sense resistor and configured to generate a signal indicative of a current through the load. One of the primary driver circuitry and the auxiliary driver circuitry is operable to drive the load with a pilot signal in a second mode of operation of the circuitry, wherein a pilot signal comprises a signal having a predefined frequency or frequency content and a predefined magnitude.

Abstract: An amplifier system may include a first feedback loop coupled between an output of an amplifier to an input of a modulator for regulating an output voltage driven at the output of the amplifier to a first terminal of a load of the amplifier system, a sense resistor for sensing a physical quantity associated with the amplifier, a second control loop coupled to the sense resistor such that the sense resistor is outside of the second control loop, the second control loop configured to regulate a common-mode voltage at a second terminal of the load, and a common-mode feedforward circuit coupled to the sense resistor and configured to minimize effects of a signal-dependent common-mode feedback of the sense resistor.

Abstract: A force sensing system for determining if a user input has occurred, the system comprising: an input channel, to receive an input from at least one force sensor; an activity detection stage, to monitor an activity level of the input from the at least one force sensor and, responsive to an activity level which may be indicative of a user input being reached, to generate an indication that an activity has occurred at the force sensor; and an event detection stage to receive said indication, and to determine if a user input has occurred based on the received input from the at least one force sensor.

Abstract: A system may include an electromagnetic actuator, a first coil configured to drive mechanical displacement of the electromagnetic actuator, a second coil configured to drive mechanical displacement of the electromagnetic actuator, and an inductance sensing subsystem having an inductance sensing path coupled to the first coil and the second coil.

Abstract: A correction unit for use in a sensor system, the sensor system comprising a force sensor configured to output a sensor signal indicative of a temporary mechanical distortion of a material under an applied force, the correction unit configured, based on the sensor signal, to: estimate an effect of the applied force on how the material will return towards an undistorted form upon a substantial reduction or removal of the applied force; and generate a corrected signal based on the estimation.

Abstract: A system may include a resonant sensor configured to sense a physical quantity, a measurement circuit communicatively coupled to the resonant sensor and configured to measure one or more resonance parameters associated with the resonant sensor and indicative of the physical quantity using an incident/quadrature detector having an incident channel and a quadrature channel and perform a calibration of a non-ideality between the incident channel and the quadrature channel of the system, the calibration comprising determining the non-ideality by controlling the sensor signal, an oscillation signal for the incident channel, and an oscillation signal for the quadrature channel; and correcting for the non-ideality.

Abstract: A method for determining sensor parameters of an actively-driven sensor system may include performing an initialization operation to establish a baseline estimate of the sensor parameters, obtaining as few as three samples of a measured physical quantity versus frequency for the actively-driven sensor system, performing a refinement operation to provide a refined version of the sensor parameters based on the as few as three samples, iteratively repeating the refinement operation until the difference between successive refined versions of the sensor parameters is below a defined threshold, and outputting the refined sensor parameters as updated sensor parameters for the actively-driven sensor system.

Abstract: A system may include a resistive-inductive-capacitive sensor configured to sense a physical quantity, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to measure one or more resonance parameters associated with the resistive-inductive-capacitive sensor and indicative of the physical quantity and, in order to maximize dynamic range in determining the physical quantity from the one or more resonance parameters, dynamically modify, across the dynamic range, either of reliance on the one or more resonance parameters in determining the physical quantity or one or more resonance properties of the resistive-inductive-capacitive sensor.

Abstract: A system may include a resonant sensor configured to sense a physical quantity, a measurement circuit communicatively coupled to the resonant sensor and configured to measure one or more resonance parameters associated with the resonant sensor and indicative of the physical quantity using an incident/quadrature detector having an incident channel and a quadrature channel and perform a calibration of a non-ideality between the incident channel and the quadrature channel of the system, the calibration comprising determining the non-ideality by controlling the sensor signal, an oscillation signal for the incident channel, and an oscillation signal for the quadrature channel; and correcting for the non-ideality.

Abstract: A system may include driving circuitry configured to drive a driving signal to an output transducer, sensing circuitry configured to sense a physical quantity associated with the output transducer in response to the driving signal, and interference detection circuitry configured to detect the presence of interference of the system and mitigate the effect of the interference in the system.

Abstract: A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to determine a measured change in a resonant frequency of the resistive-inductive-capacitive sensor and based on the measured change, modify the driving frequency.