Allegro Microsystems, LLC

Other

James M Bailey

Michael C Doogue

Jay M Towne

Glenn A Forrest

P Karl Scheller

Washington Lamar

Eric G Shoemaker

Eric Burdette

Christine M Graham

Daniel S Dwyer

Jeff Eagen

Walter M Kindred

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

Apparatus for detecting vibration of an object adapted to rotate includes one or more vibration processors selected from: a direction-change processor adapted to detect changes in a direction of rotation of the object, a direction-agreement processor adapted to identify a direction of rotation of the object in at least two channels and identify an agreement or disagreement in direction of rotation identified by the at least two channels, a phase-overlap processor adapted to identify overlapping signal regions in signals associated with the rotation of the object, and a running mode processor adapted to identify an unresponsive output signal from at least one of the at least two channels. A method for detecting the vibration of the object includes generating at least one of a direction-change output signal with the direction-change processor, a direction-agreement output signal with the direction-agreement processor, a phase-overlap output signal with the phase-overlap processor, and a running-mode-vibration output signal with the running-mode processor, each indicative of the vibration the object.

Methods and apparatus for vibration detection

Method and apparatus for vibration detection

A proximity detector has a sequential flow state machine to identify states associated with a magnetic field signal provided by a magnetic field sensing element. The proximity detector can include a vibration processor to identify a vibration in response to the states.

Proximity detector having a sequential flow state machine

Apparatus and methods for detecting passing magnetic articles including an offset adjustment circuit for adjusting the DC level of the magnetic field signal based on a dynamically adjustable offset threshold signal. The detector includes a PDAC for tracking the positive peaks of a magnetic field signal and an NDAC for tracking the negative peaks of the magnetic field signal. In one embodiment, the offset threshold signal includes a positive offset threshold signal and a negative offset threshold signal that are initially set at fixed respective signal levels and that become the level of the PDAC signal and NDAC signals, respectively, in response to a counter, that counts a number of increments of the PDAC signal and decrements of the NDAC signal, reaching a predetermined count value.

Methods and apparatus for dynamic offset adjustment in a magnetic article detector

An illuminated building number assembly (10) includes a one-piece box-like housing (12) constructed of hard molded opaque resinous plastic material and a separate one-piece front panel (14) of molded hard resinous opaque plastic. The front panel covers a housing opening (32) and includes vertical tracks (38a-e) with stops (46) at the bottom ends thereof on each side of the housing opening which allow the insertion of translucent number plates (16) from the tops thereof. A fluorescent light bulb (18) is mounted in the housing along with energizing equipment. When the front panel is mounted at the opening of the housing, the vertical tracks extend into the housing so that the number plates are prevented from moving upwardly by a top wall of the housing. Removable hard plastic mounting strips (20) are attachable at a rear wall (28) of the housing for allowing the housing to be attached externally on a building wall. The assembly can have a light sensor (68) in a separate light-sensor housing compartment to turn the fluorescent light bulb off in daytime and on at night.

Illuminated building number assembly

Growing community of inventors

Concord, NH, United States of America

James M Bailey