Patents by Inventor Vijay Mangtani

Vijay Mangtani has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7476816
    Abstract: An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and a substrate having a first surface in which is disposed one or more magnetic field sensing elements, with the first surface being proximate to the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit in a flip-chap arrangement. The lead frame also includes a shunt conductor portion formed as a coupling of the at least two leads.
    Type: Grant
    Filed: April 10, 2006
    Date of Patent: January 13, 2009
    Assignee: Allegro Microsystems, Inc.
    Inventors: Michael C. Doogue, Vijay Mangtani, William P. Taylor
  • Publication number: 20080164828
    Abstract: An electronic circuit includes circuit portions for identifying a largest voltage drop through one of a plurality of series connected diode strings and for controlling a boost switching regulator according to the largest voltage drop. The electronic circuit can sense an open circuit series connected diode string, which would otherwise have the largest voltage drop, and can disconnect that open circuit series connected diode string from control of the boost switching regulator. Another electronic circuit includes a current limiting circuit coupled to or within a boost switching regulator and configured to operate with a diode load. Another electronic circuit includes a pulse width modulation circuit configured to dim a series connected string of light emitting diodes.
    Type: Application
    Filed: January 4, 2007
    Publication date: July 10, 2008
    Inventors: Gregory Szczeszynski, Shashank Wekhande, Vijay Mangtani
  • Publication number: 20070279053
    Abstract: An integrated current sensor includes a current conductor, a magnetic field transducer, and an electromagnetic shield. The magnetic field transducer includes a sensor die. The electromagnetic shield is disposed proximate to the sensor die. The electromagnetic shield has at least one feature selected to reduce an eddy current in the electromagnetic shield.
    Type: Application
    Filed: July 11, 2007
    Publication date: December 6, 2007
    Inventors: William Taylor, John Cummings, Michael Doogue, Jay Gagnon, Vijay Mangtani, Nirmal Sharma
  • Publication number: 20070170533
    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: Application
    Filed: January 20, 2006
    Publication date: July 26, 2007
    Inventors: Michael Doogue, William Taylor, Vijay Mangtani
  • Publication number: 20070103943
    Abstract: A capacitor charging circuit is provided with a primary side output voltage sensing circuit including an RC network having an RC time constant with a predetermined relationship to the RC time constant of the output capacitor. Once the capacitor voltage reaches a fully charged level, the charging mode is terminated. The output voltage is continuously detected by measuring the voltage across the primary side RC network that decays at a predetermined rate with respect to the output capacitor and the charging mode is commenced once the RC voltage falls to a predetermined level. According to a further aspect of the invention, a switch control circuit in a flyback converter controls the switch off time in response to detection of a change in the slope polarity of the voltage at a terminal of the switch.
    Type: Application
    Filed: December 19, 2006
    Publication date: May 10, 2007
    Inventors: Vijay Mangtani, Nai-Chi Lee, Tseng-Nan Tsai, John Humenick
  • Publication number: 20060250824
    Abstract: A capacitor charging circuit is provided with a primary side output voltage sensing circuit for generating a control signal indicative of whether the output voltage has reached a desired level. The control signal is unaffected by voltage spikes occurring when the main switch is turned off. In one embodiment, the circuit filters the primary side voltage for comparison to a reference voltage in order to provide the control signal. In another embodiment, an AND gate provides the control signal indicating that the output voltage has reached the desired level only in response to the primary side voltage being greater than a reference voltage and the secondary current being discontinuous. In a further embodiment, an AND gate provides the control signal indicating that the output voltage has reached the desired levels only in response to a predetermined delay occurring after the primary side voltage becomes greater than a reference voltage and the secondary current being discontinuous.
    Type: Application
    Filed: May 9, 2005
    Publication date: November 9, 2006
    Inventors: Shashank Wekhande, Vijay Mangtani, Sihua Wen
  • Publication number: 20060219436
    Abstract: An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and a substrate having a first surface in which is disposed one or more magnetic field sensing elements, with the first surface being proximate to the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit in a flip-chap arrangement. The current sensor can also include an electromagnetic shield disposed between the current conductor portion and the magnetic field sensing elements.
    Type: Application
    Filed: May 12, 2006
    Publication date: October 5, 2006
    Inventors: William Taylor, Michael Doogue, Nirmal Sharma, Jay Gagnon, Vijay Mangtani
  • Publication number: 20060181263
    Abstract: An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and a substrate having a first surface in which is disposed one or more magnetic field sensing elements, with the first surface being proximate to the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit in a flip-chap arrangement. The lead frame also includes a shunt conductor portion formed as a coupling of the at least two leads.
    Type: Application
    Filed: April 10, 2006
    Publication date: August 17, 2006
    Inventors: Michael Doogue, Vijay Mangtani, William Taylor
  • Publication number: 20060152210
    Abstract: An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and a substrate having a first surface in which is disposed one or more magnetic field sensing elements, with the first surface being proximate to the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit in a flip-chap arrangement. The integrated circuit includes an overcurrent circuit responsive to a voltage drop generated by a current.
    Type: Application
    Filed: January 20, 2006
    Publication date: July 13, 2006
    Inventors: Vijay Mangtani, Michael Doogue, William Taylor
  • Patent number: 7075287
    Abstract: An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and a substrate having a first surface in which is disposed one or more magnetic field sensing elements, with the first surface being proximate to the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit in a flip-chap arrangement. The integrated circuit includes an overcurrent circuit responsive to a voltage drop generated by a current.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: July 11, 2006
    Assignee: Allegro Microsystems, Inc.
    Inventors: Vijay Mangtani, Michael C. Doogue, William P. Taylor
  • Patent number: 6462520
    Abstract: A differential switching converter system is disclosed. The converter system includes a plurality of switching converters having at least first and second converters. The plurality of switching converters is coupled in a differential configuration across an output load. Each converter has at least first and second transistors configured to apply and receive energy to and from an energy storage element. The converter system also includes a controller, which is configured to control the operation of the first and second transistors of each converter. The controller synchronizes turn-on and turn-off of the first transistor in the first converter with that of the first transistor in the second converter. The controller also controls turn-on and turn-off of the second transistors in the first and second converters to provide first and second duty cycles, respectively.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: October 8, 2002
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Vijay Mangtani, Leonard Harris Sherman
  • Patent number: 6424026
    Abstract: A power module has a printed circuit control component board disposed atop an IMS with an opening in the printed circuit board exposing the top surface of the IMS and power semiconductor die mounted thereon. The top surface of the IMS is closely spaced to the top surface of the printed circuit board so that wire bonds have a reduced drop from the printed circuit board to the IMS. The IMS may be cemented to the periphery of the opening in the printed circuit board, or may be located toward the top of an opening in an insulation support shell which receives a mesa from a support heat sink, which permits the close spacing of printed circuit board and IMS.
    Type: Grant
    Filed: August 2, 2000
    Date of Patent: July 23, 2002
    Assignee: International Rectifier Corporation
    Inventor: Vijay Mangtani
  • Patent number: 6272015
    Abstract: A power semiconductor device module has a plurality of spaced thermally supported substrates mounted within coplanar openings in an insulation support shall and electrically insulated from one another by the body of the insulation support shell. Each of the substrates may be a separate metal heatsink or a separate IMS sheet. Each of the substrates may receive one or more semiconductor die. A printed circuit board containing control circuits for the die is mounted above the plane of the substrate and contains openings in registry with each substrate for wire bonding the control circuits to the die. The structure permits the reduction in area of any IMS substrate or permits the elimination of the IMS.
    Type: Grant
    Filed: August 2, 2000
    Date of Patent: August 7, 2001
    Assignee: International Rectifier Corp.
    Inventor: Vijay Mangtani
  • Patent number: 6249024
    Abstract: A power module includes a three-phase inverter circuit. The positive and negative terminals of the module are centrally located on opposing sides of the module to reduce the length of the current path between the terminals. The reduced current path length significantly reduces the inductance and capacitance of the module.
    Type: Grant
    Filed: December 8, 1999
    Date of Patent: June 19, 2001
    Assignee: International Rectifier Corp.
    Inventor: Vijay Mangtani
  • Patent number: 5969964
    Abstract: A power circuit includes at least a high side and low side MOS gated transistor operable to form a bridge circuit across high and low power terminals of a power source; a high side driver circuit having an output operable to change conduction characteristics of the high side MOS gated transistor; and a series coupled diode and capacitor configured in a bootstrap arrangement with the high side and low side transistors to provide an operating voltage to the high side driver circuit.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: October 19, 1999
    Assignee: International Rectifier Corporation
    Inventor: Vijay Mangtani
  • Patent number: 5825641
    Abstract: A motor controller inverter circuit with resistive shunts for sensing the current flowing through individual legs of the motor controller. The circuit of the invention allows the use of a single monolithic three-phase driver by providing, in addition to a shunt resistor between the emitter pin of each low side IGBT and ground, an emitter return resistor between the emitter pin of each low side IGBT and the common V.sub.SO pin of the three-phase driver. The respective voltages developed across the shunt resistors can be sensed to determine the current flowing through the individual legs of the motor controller circuit.
    Type: Grant
    Filed: January 26, 1998
    Date of Patent: October 20, 1998
    Assignee: International Rectifier Corporation
    Inventor: Vijay Mangtani
  • Patent number: 5767731
    Abstract: A protection circuit for preventing momentary activation of the output of an output-isolated driver during power turn on. The protection circuit operates in a manner which prevents a buffer which is driven by the opto-isolator from turning on power transistors during power turn on, particularly in applications such as switching power supplies, motor controllers and the like.
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: June 16, 1998
    Assignee: International Rectifier Corporation
    Inventors: Vijay Mangtani, Ajit Dubhashi
  • Patent number: 5764466
    Abstract: A power circuit includes a high-side transistor, a low-side transistor and a current sensing resistor in series connection as well as a threshold detection circuit for turning off the transistors when the current in the current sensing resistor exceeds a predetermined level. The circuit further includes a driver circuit for providing a bias voltage to the low-side transistor and a voltage storing device, such as a capacitor, coupled from the low-side transistor to the driver circuit to maintain the bias voltage at a sufficient magnitude to momentarily keep the low-side transistor on during a fault condition.
    Type: Grant
    Filed: January 27, 1997
    Date of Patent: June 9, 1998
    Assignee: International Rectifier Corporation
    Inventors: Vijay Mangtani, Ajit Dubhashi
  • Patent number: 5687049
    Abstract: A fault protection circuit for protecting IGBT's and other non-latching semiconductor devices in power circuits, for example, power converting/inverting circuits, against phase to phase, phase to earth and shoot through short circuit faults as well as against over current faults. The circuit provides local protection for devices on the high side of such power circuits, and transfers the fault to the low side where it is detected and appropriate control circuitry is activated to latch the fault, thereby avoiding the need for isolcated sensing or feedback to protect the high side devices as well as the complete power circuit.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: November 11, 1997
    Assignee: International Rectifier Corporation
    Inventor: Vijay Mangtani