Eric D Shoemaker

US Patent:

20130177040, Jul 11, 2013

Filed:

Jan 6, 2012

Appl. No.:

13/345021

Inventors:

Andrea Foletto - Annecy, FR
Peter Cisar - Lenzkirch, DE
Eric Shoemaker - Pembroke NH, US

Assignee:

ALLEGRO MICROSYSTEMS, INC. - Worcester MA

International Classification:

G01K 13/08

US Classification:

374142, 374E1301

Abstract:

A magnetic field sensor includes a true power on state (TPOS) detector for which a measured threshold value is stored prior to power down and recalled upon power up. A corresponding method is associated with the magnetic field sensor.

US Patent:

20130238278, Sep 12, 2013

Filed:

Mar 6, 2012

Appl. No.:

13/413037

Inventors:

Eric Shoemaker - Pembroke NH, US
Michael C. Doogue - Manchester NH, US
Andreas P. Friedrich - Metz-Tessy, FR
Andrea Foletto - Annecy, FR

Assignee:

ALLEGRO MICROSYSTEMS, INC. - Worcester MA

International Classification:

G06F 15/00
G01B 7/30

US Classification:

702145, 32420725, 3242072, 32420721, 702151

Abstract:

A magnetic field sensor uses an angle sensor to measure and angle of rotation of a target object to which a magnet is attached. The angle sensor in combination with electronics can generate an angle sensor output signal related to a direction of a magnetic field of the magnet. The angle sensor output signal can be compared to thresholds to generate a magnetic field sensor output signal the same as a known true power on state (TPOS) sensor output signal. A corresponding method is also described.

US Patent:

20130249544, Sep 26, 2013

Filed:

Mar 20, 2012

Appl. No.:

13/424618

Inventors:

Ravi Vig - Bow NH, US
William P. Taylor - Amherst NH, US
Andreas P. Friedrich - Metz-Tessy, FR
Paul David - Bow NH, US
Marie-Adelaide Lo - Chene-Bougeries, CH
Eric Burdette - Newmarket NH, US
Eric Shoemaker - Pembroke NH, US
Michael C. Doogue - Manchester NH, US

Assignee:

ALLEGRO MICROSYSTEMS, INC. - Worcester MA

International Classification:

G01R 33/02

US Classification:

324252

Abstract:

A magnetic field sensor includes a lead frame, a semiconductor die supporting a magnetic field sensing element, a non-conductive mold material enclosing the die and a portion of the lead frame, a ferromagnetic mold material secured to the non-conductive mold material and a securing mechanism to securely engage the mold materials. The ferromagnetic mold material may comprise a soft ferromagnetic material to form a concentrator or a hard ferromagnetic material to form a bias magnet. The ferromagnetic mold material may be tapered and includes a non-contiguous central region, as may be an aperture or may contain the non-conductive mold material or an overmold material. Further embodiments include die up, lead on chip, and flip-chip arrangements, wafer level techniques to form the concentrator or bias magnet, integrated components, such as capacitors, on the lead frame, and a bias magnet with one or more channels to facilitate overmolding.

US Patent:

20180224300, Aug 9, 2018

Filed:

Apr 4, 2018

Appl. No.:

15/945085

Inventors:

- Worcester MA, US
Paul A. David - Bow NH, US
Eric G. Shoemaker - Windham NH, US

Assignee:

Allegro MicroSystems, LLC - Worcester MA

International Classification:

G01D 5/14

Abstract:

Magnetic field sensors can sense speed of movement and direction of movement of a ferromagnetic object. The magnetic field sensors employ both planar Hall effect elements and vertical Hall effect elements to generate two-state signals in two different signal paths with relative phases that are ninety degrees apart, the ninety degrees having sufficient margin to aid in detection of the direction of motion. Other magnetic field sensors use at least four vertical Hall effect elements to identify a speed of rotation and a direction of rotation of a moving ferromagnetic object.

US Patent:

20170356761, Dec 14, 2017

Filed:

Jun 8, 2016

Appl. No.:

15/176665

Inventors:

- Worcester MA, US
Paul A. David - Bow NH, US
Eric G. Shoemaker - Windham NH, US

Assignee:

Allegro MicroSystems, LLC - Worcester MA

International Classification:

G01D 5/14

Abstract:

Magnetic field sensors can sense speed of movement and direction of movement of a ferromagnetic object. The magnetic field sensors employ both planar Hall effect elements and vertical Hall effect elements to generate two-state signals in two different signal paths with relative phases that are ninety degrees apart, the ninety degrees having sufficient margin to aid in detection of the direction of motion. Other magnetic field sensors use at least four vertical Hall effect elements to identify a speed of rotation and a direction of rotation of a moving ferromagnetic object.

US Patent:

20160313407, Oct 27, 2016

Filed:

Apr 27, 2015

Appl. No.:

14/696674

Inventors:

- Worcester MA, US
P. Karl Scheller - Bow NH, US
Eric G. Shoemaker - Pembroke NH, US

Assignee:

Allegro Microsystems, LLC - Worcester MA

International Classification:

G01R 33/00
G01R 33/09
G01R 33/07
H03F 1/02
H03G 1/00

Abstract:

A circuit includes a current source having at least first terminal and a second, control terminal. The current source is configured to receive a current control signal at the control terminal and in response thereto generates a first current signal at the first terminal. The current control signal controls a current level of the first current signal. The circuit also includes at least one sensing element responsive to one or more sense parameters and having an input adapted to couple to the first terminal of said current source. The sensing element is configured to receive one or more current signals comprising at least the first current signal and in response thereto generates a sensed output signal at an output thereof. A corresponding method for operating the circuit is also provided.

US Patent:

20160200245, Jul 14, 2016

Filed:

Jan 12, 2016

Appl. No.:

14/993495

Inventors:

- Worcester MA, US
Gerardo A. Monreal - Pilar, AR
Christine M. Graham - Bow NH, US
Eric G. Shoemaker - Windham NH, US

Assignee:

Allegro Microsystems, LLC - Worcester MA

International Classification:

B60Q 3/02
G05F 3/08
B60Q 3/06
H05B 33/08
G01R 33/07
G01R 33/00

Abstract:

An integrated magnetic field sensor includes a magnetic field sensing circuit and a power driving circuit disposed upon or within a common substrate. A method of powering on and off a load uses the above integrated magnetic field sensor.

US Patent:

20140375312, Dec 25, 2014

Filed:

Jun 17, 2014

Appl. No.:

14/306722

Inventors:

- Worcester MA, US
Andrea Foletto - Annecy, FR
Jay M. Towne - Bow NH, US
Michael Morris - Deerfield NH, US
Eric Shoemaker - Pembroke NH, US

Assignee:

ALLEGRO MICROSYSTEMS, LLC - Worcester MA

International Classification:

G01R 33/02
G01R 33/09
G01R 33/07

US Classification:

324259

Abstract:

A magnetic field sensor and associated method provide an output signal with an identifiable encoding to indicate when a signature region in a moving target proximate to the magnetic field sensor passes by the magnetic field sensor.