Abstract: A sensor integrated circuit including a regulator for generating a regulated voltage includes a digital load configured to draw a load current from the regulator in response to a clock signal during in situ operation and a comparator configured to determine the absence or presence of a fault during in situ operation. The load current is less than or equal to a predetermined level in the absence of a fault and is greater than the predetermined level in the presence of a fault. The comparator is responsive to the load current and to a threshold level and is configured to generate a comparator output signal having a level indicative of whether the load current is less than or greater than the threshold level in order to thereby determine the absence or presence of a fault during in situ operation, respectively.
Type:
Grant
Filed:
January 18, 2019
Date of Patent:
March 16, 2021
Assignee:
Allegro MicroSystems, LLC
Inventors:
Glenn A. Forrest, Thomas J. Kovalcik, Wei Zhang
Abstract: A magnetoresistance element structure disposed parallel to an x-y plane defined by an x-axis and a y-axis orthogonal to the x-axis can include a first magnetoresistance element having a plurality of first shapes coupled in series to result in the first magnetoresistance element having a first serpentine shape parallel to the x-y plane; and a second magnetoresistance element having a plurality of second shapes coupled in series to result in the second magnetoresistance element having a second serpentine shape parallel to the x-y plane, wherein the plurality of first shapes and the plurality of second shapes are disposed in an interdigitated pattern. A magnetic field sensor can use the above magnetoresistance element structure. Nested magnetoresistance elements and magnetic field sensors are also described.
Abstract: A metal-oxide semiconductor (MOS) transistor structure is provided herein having one or more horizontal and/or one or more vertical MOS transistor structures formed around trench and liner isolation regions. The trench region serves as a gate electrode, while the liner is formed around the sidewalls of trench region and serves as a gate dielectric of a parasitic MOS within the transistor structure. The MOS transistor structure includes various doped regions formed around one or more portions of the trench and liner regions. The doped regions can have one or more different doping types such that in response to a voltage applied to the trench region, a channel region is formed in at least one of the doped regions and provides a current path within the MOS transistor between different doped regions.
Type:
Grant
Filed:
August 12, 2019
Date of Patent:
March 9, 2021
Assignee:
Allegro MicroSystems, LLC
Inventors:
Sundar Chetlur, Maxim Klebanov, Washington Lamar
Abstract: In one aspect, a dual tunnel magnetoresistance (TMR) element structure includes a first TMR element and a second TMR element. The TMR element structure also includes a conducting layer that is disposed between the first TMR element and the second TMR element and is in direct contact with the first TMR element and the second TMR element.
Abstract: In one aspect, a tunnel magnetoresistance (TMR) element includes a magnesium oxide (MgO) layer, a cobalt iron boron (CoFeB) layer in direct contact with the MgO layer and a cobalt iron (CoFe) layer. The TMR element also includes a tantalum layer in direct contact with the CoFeB layer and the CoFe layer.
Type:
Application
Filed:
September 18, 2019
Publication date:
March 4, 2021
Applicant:
Allegro MicroSystems, LLC
Inventors:
Paolo Campiglio, Amal Hamdache, Julien Voillot
Abstract: In one aspect, a magnetic field sensor includes a plurality of tunneling magnetoresistance (TMR) elements that includes a first TMR element, a second TMR element, a third TMR element and a fourth TMR element. The first and second TMR elements are connected to a voltage source and the third and fourth TMR elements are connected to ground. Each TMR element has a pillar count of more than one pillar and the pillar count is selected to reduce the angle error below 1.0°.
Type:
Application
Filed:
August 28, 2019
Publication date:
March 4, 2021
Applicant:
ALLEGRO MICROSYSTEMS, LLC
Inventors:
Rémy Lassalle-Balier, Pierre Belliot, Christophe Hoareau, Jean-Michel Daga
Abstract: Systems and methods described herein provide a current sensor based on magnetic field detection having multiple sensor arrangements with multiple, different sensitivity ranges. The outputs of the multiple sensor arrangements can be combined to generate a single output signal. The current sensor can include two or more sensor arrangements, each having one or more magnetic field sensing elements, and configured to sense a magnetic field in different first measurement ranges corresponding to different ranges of currents through the conductor and further configured to generate different magnetic field signals indicative of the sensed magnetic field in the respective measurement range. The current sensor can include a circuit configured to generate an output signal indicative of a combination of the different magnetic field signals that corresponds to the current through the conductor.
Type:
Grant
Filed:
August 20, 2018
Date of Patent:
March 2, 2021
Assignees:
Allegro MicroSystems, LLC, Commissariat à l'énergie atomique et aux énergies alternatives
Inventors:
Noémie Belin, Shaun D. Milano, Wade Bussing, Claude Fermon
Abstract: A system for reducing stray field effects comprises a magnetic target producing a changing magnetic field; a first set of magnetic field sensing elements placed in spaced relation to the magnetic target and comprising at least a first magnetic field sensing element and a second magnetic field sensing element, each magnetic field sensing element having an axis of maximum sensitivity; a second set of magnetic field sensing elements placed in spaced relation to the magnetic target and comprising at least a third magnetic field sensing element and a fourth magnetic field sensing element, each magnetic field sensing element having an axis of maximum sensitivity; and wherein the first set of magnetic field sensing elements is positioned closer to a center point of the magnetic field than the second set of magnetic field sensing elements.
Type:
Application
Filed:
November 9, 2020
Publication date:
February 25, 2021
Applicant:
Allegro MicroSystems, LLC
Inventors:
Nevenka Kozomora, William Wilkinson, Braden Blanchette
Abstract: Methods and apparatus for a signal isolator IC package including a die having a first die portion isolated from a second die portion. The first die portion is surrounded on six sides by first insulative material and the second die portion is surrounded on six sides by second insulative material. The first die portion provides a first voltage domain and the second die portion provides a second voltage domain. The signal isolator comprises a first signal path between the first die portion and the second die portion, wherein the first signal path is isolated with respect to the first and second die portions.
Type:
Application
Filed:
August 22, 2019
Publication date:
February 25, 2021
Applicant:
Allegro MicroSystems, LLC
Inventors:
Robert A. Briano, Bruno Luis Uberti, Alejandro Gabriel Milesi, Gerardo A. Monreal
Abstract: An apparatus including a magnetoresistance element having conductive contacts disposed between the magnetoresistance element and a semiconductor substrate.
Type:
Application
Filed:
November 5, 2020
Publication date:
February 25, 2021
Applicant:
Allegro MicroSystems, LLC
Inventors:
Yen Ting Liu, Maxim Klebanov, Bryan Cadugan, Sundar Chetlur, Harianto Wong
Abstract: A method of providing a sensor IC package can include applying a film to a leadframe having first and second surfaces, mounting at least one component to the film, and applying a pre-mold material to cover at least a portion of the leadframe and the passive component while leaving a first side of the leadframe exposed. The film can be removed and a die attached to the first side of the leadframe. At least one electrical connection can be formed between the die and the leadframe. The assembly of the die, the leadframe, and the pre-mold material can be encapsulated with a final mold material to provide a low profile IC package.
Type:
Application
Filed:
August 22, 2019
Publication date:
February 25, 2021
Applicant:
Allegro MicroSystems, LLC
Inventors:
Paul A. David, Harry Chandra, William P. Taylor
Abstract: A data storage circuit for storing data from volatile memory in response to a power loss, the data storage circuit including an input for receiving a power loss signal in response to a power loss from at least one power source, an input configured to receive data from a volatile memory, a single block of non-volatile matrix of memory cells and a driver circuit coupled to said single row of non-volatile matrix of memory cells. The driver circuit is configured to write data to and read data from said single block of non-volatile matrix of memory cells. The single block of non-volatile matrix of memory cells can be provided as a single row electrically erasable programmable read only memory (EEPROM).
Type:
Grant
Filed:
August 14, 2019
Date of Patent:
February 23, 2021
Assignee:
Allegro MicroSystems, LLC
Inventors:
Juan Manuel Cesaretti, Alejandro Gabriel Milesi
Abstract: Methods and apparatus for an IC package having an impedance detector module configured to have: a first connection to a first external energy source via a first IO pin of the IC package and a second connection to a detection component. In embodiments, the detection component is configured for connection to a first ground for the first external energy source via a second IO pin of the IC package, and to a barrier component, which is configured for connection to a second ground for a second external energy source via a third IO pin of the IC package. The impedance detector module is configured to detect a disconnection or degradation of a connection to ground.
Abstract: A monitor circuit for monitoring a level of a first and second regulated source may monitor a voltage level of regulated voltages or a current level of regulated currents. In an embodiment, the monitor circuit includes circuitry responsive to a first regulated current and to a second regulated current. A first circuit responsive to the first regulated current and to the second regulated current generates a first error signal indicative of at least one of an overcurrent condition of the first regulated current and an undercurrent condition of the second regulated current. A second circuit responsive to the first regulated current and to the second regulated current generates a second error signal indicative of at least one of an undercurrent condition of the first regulated current and an overcurrent condition of the second regulated current. A method for monitoring the levels of first and second regulated sources is also provided.
Type:
Application
Filed:
October 2, 2020
Publication date:
February 18, 2021
Applicant:
Allegro MicroSystems, LLC
Inventors:
Sam Tran, Jay M. Towne, P. Karl Scheller
Abstract: A method is provided comprising: obtaining a temperature reading by using a temperature sensing element that is part of a magnetic field sensor; obtaining a stress reading by using a stress sensing element that is part of the magnetic field sensor; calculating a stress difference using the temperature reading and the stress reading, the stress difference including a difference between an expected stress associated with the temperature reading and the stress reading obtained from the stress sensing element; and adjusting a gain of a sensing element signal based on the stress difference, the sensing element signal being generated at least in part by a magnetic field sensing element that is part of the magnetic field sensor.
Abstract: A system is provided for driving a load such as a multi-phase motor. The system includes a motor driver that has a plurality of switches coupled to a motor to drive a current through each of a plurality of phase coils of the motor. A polarity detection circuit detects a polarity of the current in one or more of the phase coils of the motor to generate a polarity value that represents the detected current polarity. The polarity detection circuit can include at least one comparator that has a first input coupled to a node between two of the plurality of switches, a second input coupled to receive a threshold value, and an output from which the polarity value is provided. Further included is a controller that is configured to provide a plurality of pulse width modulated (PWM) output control signals to the plurality of switches to control the switches to drive the current through the plurality of phase coils of the motor.
Type:
Grant
Filed:
August 8, 2019
Date of Patent:
February 16, 2021
Assignee:
Allegro MicroSystems, LLC
Inventors:
Kamyar Khosravi, Masahira Kurihara, Gianluca Allegrini, Robert D. Christie
Abstract: A method of determining an error condition in a magnetic field sensor can include receiving a first bridge signal, the first bridge signal generated by a first full bridge circuit. The method can also include receiving a second bridge signal, the second bridge signal generated by a second full bridge circuit. The method can also include determining a bridge separation from the first bridge signal and the second bridge signal. The method can also include comparing a function of the bridge separation to a threshold value. The method can also include generating an error signal indicative of the error condition or not indicative of the error condition in response to the comparing.
Type:
Grant
Filed:
November 29, 2017
Date of Patent:
February 16, 2021
Assignee:
Allegro MicroSystems, LLC
Inventors:
Rémy Lassalle-Balier, Jeffrey Eagen, Paul A. David
Abstract: Methods and apparatus for a magnetic field sensor integrated circuit including a lead frame having a first surface, a second opposing surface, and a plurality of leads. A substrate has a first surface supporting a magnetic field sensing element and a second surface attached to the first surface of the lead frame. A magnet has a first surface and a second, opposing surface, and is configured to generate a magnetic field. A spacer is positioned between the first surface of the magnet and the second surface of the lead frame with a thickness selected to establish a predetermined distance between the first surface of the magnet and the magnetic field sensing element, the predetermined distance selected to provide the magnetic field signal as a sinusoidal signal.
Abstract: A magnetic field sensor for detecting motion of an object includes one or more magnetic field sensing elements configured to generate a magnetic field signal in response to a magnetic field associated with the object. A motion detector responsive to the magnetic field signal and to a threshold signal is configured to generate a detector output signal having edges occurring in response to a comparison of the magnetic field signal and the threshold signal. A speed detector responsive to the detector output signal generates a speed signal indicative of a speed of motion of the object. A delay processor is responsive to the speed signal and configured to determine a delay for the detector output signal based on the speed of motion of the object.
Abstract: Methods and apparatus for a TMR-based sensor having a first magnetic field sensing element comprising a bridge having first, second, third, and fourth legs. Legs of the bridge comprise TMR elements with pillars connected to one or more switch matrixes to adjust total resistances of the bridge legs. Equalizing the resistance of the bridge legs can enhance sensor performance.