A magnetic field sensor includes built in self-test circuits that allow a self-test of most of, or all of, the circuitry of the magnetic field sensor, including self-test of a magnetic field sensing element used within the magnetic field sensor, while the magnetic field sensor is functioning in normal operation.

Circuits and Methods for Generating a Self-Test of a Magnetic Field Sensor

A magnetic field sensor includes a diagnostic circuit that allows a self-test of most of, or all of, the circuitry of the magnetic field sensor, including a self-test of a magnetic field sensing element used within the magnetic field sensor. The magnetic field sensor can generate a diagnostic magnetic field to which the magnetic field sensor is responsive.

Circuits and methods for generating a diagnostic mode of operation in a magnetic field sensor

A magnetic field sensor includes a reference-field-sensing circuit channel that allows a calibration or a self-test of the circuitry of the magnetic field sensor. The magnetic field sensor can generate a reference magnetic field to which the magnetic field sensor is responsive.

Circuits and methods for self-calibrating or self-testing a magnetic field sensor

A magnetic field sensor includes a reference-field-sensing circuit channel that allows a self-test or a self-calibration of the circuitry of the magnetic field sensor. The self-test or the self calibration can have at least two different bandwidths that provide a respective at least two different rates of self-test or self-calibration.

Circuits and methods using adjustable feedback for self-calibrating or self-testing a magnetic field sensor with an adjustable time constant

A circuit to detect a movement of an object has a calibration time period that ends when peak detectors in the circuit stop updating for a predetermined amount of time. A method associated with the circuit is also described.

Circuits and Methods for Calibration of a Motion Detector

A proximity detector employs a first peak detector circuit and a second peak detector circuit, both responsive to a magnetic field signal. The second peak detector circuit includes a positive peak detector circuit and a negative peak detector circuit, each of which have a predetermined excursion limit in an outward direction away from a center voltage of the magnetic field signal so as to be less affected by a large signature region in the magnetic field signal. The proximity detector also includes an output control circuit. The output control circuit is configured to provide an output signal, which, during a determined time period, changes state in response to the first peak detector circuit, and which, after the determined time period, changes state in response to the second peak detector circuit.

Calibration circuits and methods for proximity detector

A circuit to detect a movement of an object includes a magnetic field sensing element for generating a magnetic field signal proportional to a magnetic field associated with the object and a motion detector to generate a motion signal indicative of the movement of the object. The motion detector includes a peak identifying circuit to provide a peak signal and a peak sample selection module that selects a sample associated with one or more prior cycles of a magnetic field signal to generate a selected peak signal. The motion detector further includes a threshold generator to generate a threshold signal as a function of the selected peak signal and a comparator to compare the threshold signal with the magnetic field signal to generate the motion signal. Peak samples from prior magnetic field signal cycles may be averaged for use to establish the threshold signal. A method associated with the circuit is also described.

Circuits and methods for generating a threshold signal used in a magnetic field sensor based on a peak signal associated with a prior cycle of a magnetic field signal

Calibration circuits and methods for a proximity detector using a first rotation detector for a determined time period and a second rotation detector after the determined time period

Methods and apparatus for an integrated circuit that includes a supply voltage transient detection module (102) to activate a hold output signal (HOLD_OUT) that causes the output (109) to remain in its present state and to activate a hold processing signal (HOLD_PROC) that causes a signal processing module (106) to remain in its present state. In one embodiment, the output remains in that state until the supply voltage returns to a normal operating range and the hold signal transitions to an inactive state.

Methods and apparatus for supply voltage transient protection

Methods and apparatus for an integrated circuit that includes a supply voltage transient detection module to activate a hold signal that causes the output to remain in its present state. In one embodiment, the output remains in that state until the supply voltage returns to a normal operating range and the hold signal transitions to an inactive state.

Jeff Eagen

Papers

Calibration circuits and methods for proximity detector

Circuits and methods for generating a threshold signal used in a magnetic field sensor based on a peak signal associated with a prior cycle of a magnetic field signal

Calibration circuits and methods for a proximity detector using a first rotation detector for a determined time period and a second rotation detector after the determined time period

Methods and apparatus for supply voltage transient protection

Methods and apparatus for supply voltage transient protection for maintaining a state of a sensor output signal