Abstract: Electronic circuits provide an error signal to control a regulated output voltage signal generated by a controllable DC-DC converter for driving one or more series connected strings of light emitting diodes.
Abstract: Motor control circuits and associated methods to control an electric motor provide an ability to synchronize a rotational speed of the electric motor with an external clock signal, resulting in reduced jitter in the rotational speed of the electric motor.
Abstract: A level shift circuit is configured to control a high side transistor of a half bridge circuit. The level shift circuit has composite current mirrors and other circuits that reduce the effect of transient voltages that are produced as the half bridge circuit is switched.
Abstract: A control loop circuit for use in a closed-loop control system that controls a system such as a linear motor is presented. The control loop circuit includes a lead-lag compensator that features a lead compensation network configured to reduce output noise without substantially changing the effect of the lead compensation in the control system's frequency response.
Abstract: An integrated circuit can have a first substrate supporting a magnetic field sensing element and a second substrate supporting another magnetic field sensing element. The first and second substrates can be arranged in a variety of configurations. Another integrated circuit can have a first magnetic field sensing element and second different magnetic field sensing element disposed on surfaces thereof.
Type:
Grant
Filed:
June 2, 2010
Date of Patent:
January 14, 2014
Assignee:
Allegro Microsystems, LLC
Inventors:
Michael C. Doogue, William P. Taylor, Vijay Mangtani
Abstract: Methods and apparatus to provide an integrated circuit package having a conductive leadframe, a non-conductive die paddle mechanically coupled to the leadframe, and a die disposed on the die paddle and electrically connected to the leadframe. With this arrangement, eddy currents are reduced near the magnetic field transducer to reduce interference with magnetic fields.
Type:
Grant
Filed:
January 16, 2012
Date of Patent:
January 14, 2014
Assignee:
Allegro Microsystems, LLC
Inventors:
Shaun D. Milano, Michael C. Doogue, William P. Taylor
Abstract: An apparatus and a method provide an output signal indicative of a speed of rotation and a direction of rotation of a ferromagnetic object capable of rotating. A variety of signal formats of the output signal are described.
Abstract: 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.
Type:
Application
Filed:
August 19, 2013
Publication date:
December 19, 2013
Applicant:
Allegro Microsystems, LLC
Inventors:
Juan Manuel Cesaretti, Gerardo A. Monreal, William P. Taylor, Michael C. Doogue
Abstract: In one aspect, a circuit includes a plurality of comparators. Each comparator is configured to receive a first input from a corresponding load of a plurality of loads and to receive a second input as a regulation voltage. The circuit also includes an amplifier configured to receive signals provided by the plurality of comparators, a pulse-width modulation (PWM) circuit configured to receive a control signal from the amplifier and to provide a signal to a primary switch to control voltage provided to the loads and an output switch sequencer coupled to each of the comparators and configured to provide control signals to control switches coupled to the primary switch enabling one control switch to be active at a time. Each control switch provides a voltage increase to a respective load of the plurality of loads if enabled.
Abstract: An integrated circuit (IC) current sensor that self-calibrates to adjust its signal gain when employed in a current divider configuration is presented. The current sensor includes an integrated current conductor, a magnetic field transducer, a controllable gain stage and a calibration controller. The integrated current conductor is adapted to receive a portion of a calibration current. The calibration current corresponds to a full scale current. The magnetic field transducer, responsive to the calibration current portion, provides a magnetic field signal having a magnitude proportional to a magnetic field generated by the calibration current portion. The controllable gain stage is configured to amplify the magnetic field signal with an adjustable gain to provide an amplified magnetic field signal.
Abstract: A circuit to detect a movement of an object provides a threshold selection module that uses one or more threshold signals identified prior to a present cycle of magnetic field signal in order to establish a threshold signal used for a present cycle of the magnetic field signal. A method associated with the circuit is also described.
Abstract: A magnetic field sensor including a bidirectional node is configured to perform at least one of generating sensor data, storing sensor data, or communicating sensor data in a serial data signal in response to a trigger signal received at the bidirectional node. An alternative sensor having a node that may or may not be a bidirectional node is configured to reset at least one of a sensor data signal, a clock, a register, or a counter in response to a trigger signal received at the node and is further configured to communicate the sensor data signal in response to the trigger signal.
Type:
Grant
Filed:
December 15, 2010
Date of Patent:
November 5, 2013
Assignee:
Allegro Microsystems, LLC
Inventors:
Mark J. Donovan, Craig S. Petrie, Nevenka Kozomora, Michael C. Doogue
Abstract: A magnetic field sensor includes a Hall element configured to generate a Hall element output signal in response to a magnetic field, the Hall element output signal comprising a magnetic field signal component and an offset signal component. The magnetic field sensor also includes a Hall element modulation circuit coupled to receive the Hall element output signal and configured to generate a modulation circuit output signal. The Hall element modulation circuit is modulated with a modulation signal having a changing modulation frequency that changes between a minimum frequency and a maximum frequency.
Abstract: A magnetic field sensor includes a lead frame having a plurality of leads, at least two of which have a connection portion and a die attach portion. A semiconductor die is attached to the die attach portion of the at least two leads. In some embodiments, at least one passive component is attached to the die attach portion of at least two leads.
Type:
Application
Filed:
January 25, 2013
Publication date:
September 26, 2013
Applicant:
Allegro Microsystems, LLC
Inventors:
Paul David, William P. Taylor, P. Karl Scheller, Ravi Vig, Andreas P. Friedrich
Abstract: A motion sensor has an output protocol processor configured to provide a validated output signal after a determined time period, wherein the determined time period is extended if a vibration is detected.
Type:
Application
Filed:
April 9, 2013
Publication date:
September 26, 2013
Applicant:
Allegro Microsystems, LLC
Inventors:
Andrea Foletto, Devon Fernandez, Eric Burdette
Abstract: A magnetic field sensor includes a lead frame, a semiconductor die having a first surface in which a magnetic field sensing element is disposed and a second surface attached to the lead frame, and a non-conductive mold material enclosing the die and at least a portion of the lead frame. The sensor may include a ferromagnetic mold material secured to a portion of the non-conductive mold material. Features include a multi-sloped taper to an inner surface of a non-contiguous central region of the ferromagnetic mold material, a separately formed element disposed in the non-contiguous central region, one or more slots in the lead frame, a molded ferromagnetic suppression device spaced from the non-conductive mold material and enclosing a portion of a lead, a passive device spaced from the non-conductive mold material and coupled to a plurality of leads, and a ferromagnetic bead coupled to a lead.
Type:
Application
Filed:
January 24, 2013
Publication date:
September 26, 2013
Applicant:
Allegro Microsystems, LLC
Inventors:
Ravi Vig, William P. Taylor, Paul David, P. Karl Scheller, Andreas P. Friedrich
Abstract: 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.
Type:
Grant
Filed:
July 21, 2010
Date of Patent:
September 24, 2013
Assignee:
Allegro Microsystems, LLC
Inventors:
Juan Manuel Cesaretti, Gerardo Monreal, William P. Taylor, Michael C. Doogue
Abstract: A magnetic field sensor includes a compensation loop coupled in series with normal circuit couplings in order to reduce a transient signal that would otherwise be generated when the magnetic field sensor experiences a high rate of change of magnetic field. In some embodiments, the magnetic field sensor is a current sensor responsive to a magnetic field generated by a current-carrying conductor.
Abstract: A motion sensor has a state processor to identify states associated with a magnetic field signal provided by a magnetic field sensing element. The state processor includes a state peak logic module configured to generate states that have a reduced amount of state chatter.
Abstract: A magnetic field sensor includes a compensation loop coupled in series with normal circuit couplings in order to reduce a transient signal that would otherwise be generated when the magnetic field sensor experiences a high rate of change of magnetic field. In some embodiments, the magnetic field sensor is a current sensor responsive to a magnetic field generated by a current-carrying conductor.