Allegro Microsystems, LLC

Jeff Eagen

P Karl Scheller

Devon Fernandez

Glenn A Forrest

Jay M Towne

Eric G Shoemaker

Eric Burdette

Mathew Drouin

James M Bailey

Karl Scheller

Christine M Graham

Daniel S Dwyer

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.

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

An integrated circuit includes an output driver circuit having a plurality of output driver devices connected in a parallel arrangement and an output driver controller that is capable of individually controlling the conducting states of the output driver devices. In at least one embodiment, the controller is capable of achieving any of a plurality of different fall times (and/or rise times) in an output signal by appropriately controlling the conducting states of the output devices if a change in the state of the output signal is desired, in some implementations, the controller is capable of achieving different waveshapes during rising and/or failing edges of an output signal.

Output driver having improved electromagnetic compatibility (EMC) and associated methods

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

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

A track-and-hold peak detector circuit, which can operate at low input signal frequencies, includes a capacitor to hold a peak voltage of the input signal and logic circuitry that reduces an effect of leakage current into or out of the capacitor, and therefore, provides protection against self-switching of an output signal of the peak detector circuit.

Growing community of inventors

Manchester, NH, United States of America

Jeff Eagen