Patents by Inventor Sriram Chandrasekaran

Sriram Chandrasekaran 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: 10784859
    Abstract: A gate drive circuit for generating asymmetric drive voltages comprises a gate drive transformer comprising: a primary winding responsive to a pulse width module (PWM) input signal to generate a bipolar signal having a positive bias voltage and a negative bias voltage; and a secondary winding responsive to the bipolar signal to generate a PWM output signal. A first charge pump is connected to the secondary winding responsive to the PWM output signal to generate a level shifted PWM output signal. A second charge pump is connected to the secondary winding to generate a readjusted PWM output signal by decreasing at least a portion of the level shifted PWM output signal. A gate switching device is connected to the first charge pump and second charge pump. A level shifted PWM output signal establishes an ON condition and the readjusted PWM output signal establishes an OFF condition of the gate MOSFET.
    Type: Grant
    Filed: July 23, 2019
    Date of Patent: September 22, 2020
    Assignee: Raytheon Company
    Inventors: Sriram Chandrasekaran, Michael S. Hockema
  • Patent number: 10778218
    Abstract: A gate drive circuit for generating asymmetric drive voltages comprises a gate drive transformer comprising: a primary winding responsive to a pulse width module (PWM) input signal to generate a bipolar signal having a positive bias voltage and a negative bias voltage; and a secondary winding responsive to the bipolar signal to generate a PWM output signal. A first charge pump is connected to the secondary winding responsive to the PWM output signal to generate a level shifted PWM output signal. A second charge pump is connected to the secondary winding to generate a readjusted PWM output signal by decreasing at least a portion of the level shifted PWM output signal. A gate switching device is connected to the first charge pump and second charge pump. A level shifted PWM output signal establishes an ON condition and the readjusted PWM output signal establishes an OFF condition of the gate MOSFET.
    Type: Grant
    Filed: July 23, 2019
    Date of Patent: September 15, 2020
    Assignee: Raytheon Company
    Inventors: Sriram Chandrasekaran, Michael S. Hockema
  • Publication number: 20200106436
    Abstract: A gate drive circuit for generating asymmetric drive voltages comprises a gate drive transformer comprising: a primary winding responsive to a pulse width module (PWM) input signal to generate a bipolar signal having a positive bias voltage and a negative bias voltage; and a secondary winding responsive to the bipolar signal to generate a PWM output signal. A first charge pump is connected to the secondary winding responsive to the PWM output signal to generate a level shifted PWM output signal. A second charge pump is connected to the secondary winding to generate a readjusted PWM output signal by decreasing at least a portion of the level shifted PWM output signal. A gate switching device is connected to the first charge pump and second charge pump. A level shifted PWM output signal establishes an ON condition and the readjusted PWM output signal establishes an OFF condition of the gate MOSFET.
    Type: Application
    Filed: July 23, 2019
    Publication date: April 2, 2020
    Inventors: Sriram Chandrasekaran, Michael S. Hockema
  • Publication number: 20200106435
    Abstract: A gate drive circuit for generating asymmetric drive voltages comprises a gate drive transformer comprising: a primary winding responsive to a pulse width module (PWM) input signal to generate a bipolar signal having a positive bias voltage and a negative bias voltage; and a secondary winding responsive to the bipolar signal to generate a PWM output signal. A first charge pump is connected to the secondary winding responsive to the PWM output signal to generate a level shifted PWM output signal. A second charge pump is connected to the secondary winding to generate a readjusted PWM output signal by decreasing at least a portion of the level shifted PWM output signal. A gate switching device is connected to the first charge pump and second charge pump. A level shifted PWM output signal establishes an ON condition and the readjusted PWM output signal establishes an OFF condition of the gate MOSFET.
    Type: Application
    Filed: July 23, 2019
    Publication date: April 2, 2020
    Inventors: Sriram Chandrasekaran, Michael S. Hockema
  • Patent number: 10574129
    Abstract: A reconfigurable power converter is provided that includes a pulse-width modulation (PWM) controller. The PWM controller is configured to switch between a first modulation scheme and a second modulation scheme when a current-level property crosses a transition threshold.
    Type: Grant
    Filed: May 4, 2018
    Date of Patent: February 25, 2020
    Assignee: Raytheon Company
    Inventor: Sriram Chandrasekaran
  • Publication number: 20190341840
    Abstract: A reconfigurable power converter is provided that includes a pulse-width modulation (PWM) controller. The PWM controller is configured to switch between a first modulation scheme and a second modulation scheme when a current-level property crosses a transition threshold.
    Type: Application
    Filed: May 4, 2018
    Publication date: November 7, 2019
    Inventor: Sriram Chandrasekaran
  • Patent number: 10361698
    Abstract: A gate drive circuit for generating asymmetric drive voltages comprises a gate drive transformer comprising: a primary winding responsive to a pulse width module (PWM) input signal to generate a bipolar signal having a positive bias voltage and a negative bias voltage; and a secondary winding responsive to the bipolar signal to generate a PWM output signal. A first charge pump is connected to the secondary winding responsive to the PWM output signal to generate a level shifted PWM output signal. A second charge pump is connected to the secondary winding to generate a readjusted PWM output signal by decreasing at least a portion of the level shifted PWM output signal. A gate switching device is connected to the first charge pump and second charge pump. A level shifted PWM output signal establishes an ON condition and the readjusted PWM output signal establishes an OFF condition of the gate MOSFET.
    Type: Grant
    Filed: January 23, 2017
    Date of Patent: July 23, 2019
    Assignee: Raytheon Company
    Inventors: Sriram Chandrasekaran, Michael S. Hockema
  • Publication number: 20180241391
    Abstract: A gate drive circuit for generating asymmetric drive voltages comprises a gate drive transformer comprising: a primary winding responsive to a pulse width module (PWM) input signal to generate a bipolar signal having a positive bias voltage and a negative bias voltage; and a secondary winding responsive to the bipolar signal to generate a PWM output signal. A first charge pump is connected to the secondary winding responsive to the PWM output signal to generate a level shifted PWM output signal. A second charge pump is connected to the secondary winding to generate a readjusted PWM output signal by decreasing at least a portion of the level shifted PWM output signal. A gate switching device is connected to the first charge pump and second charge pump. A level shifted PWM output signal establishes an ON condition and the readjusted PWM output signal establishes an OFF condition of the gate MOSFET.
    Type: Application
    Filed: January 23, 2017
    Publication date: August 23, 2018
    Inventors: Sriram Chandrasekaran, Michael S. Hockema
  • Patent number: 9736219
    Abstract: Methods, systems, and computer-readable media for managing open shares in an enterprise computing environment are presented. In some embodiments, a computer system may receive a request to scan one or more servers for open shares. Then, the computer system may validate one or more input files associated with the request and verify access to the one or more servers. Next, the computer system may scan the one or more servers to create a runtime share list file identifying one or more open shares. Subsequently, the computer system may identify at least one open share to be remediated and may apply one or more remediation actions to the at least one open share. Thereafter, the computer system may update an output file to include remediation information identifying the one or more remediation actions applied to the at least one open share and may send the output file.
    Type: Grant
    Filed: June 26, 2015
    Date of Patent: August 15, 2017
    Assignee: Bank of America Corporation
    Inventors: Chirag Kansagra, William O'Callaghan, Minesh Shah, Ketankumar Modi, Mubarak Chanbaig, Ritesh Pandey, Sriram Chandrasekaran
  • Publication number: 20160381117
    Abstract: Methods, systems, and computer-readable media for managing open shares in an enterprise computing environment are presented. In some embodiments, a computer system may receive a request to scan one or more servers for open shares. Then, the computer system may validate one or more input files associated with the request and verify access to the one or more servers. Next, the computer system may scan the one or more servers to create a runtime share list file identifying one or more open shares. Subsequently, the computer system may identify at least one open share to be remediated and may apply one or more remediation actions to the at least one open share. Thereafter, the computer system may update an output file to include remediation information identifying the one or more remediation actions applied to the at least one open share and may send the output file.
    Type: Application
    Filed: June 26, 2015
    Publication date: December 29, 2016
    Inventors: Chirag Kansagra, William O'Callaghan, Minesh Shah, Ketankumar Modi, Mubarak Chanbaig, Ritesh Pandey, Sriram Chandrasekaran
  • Patent number: 9379629
    Abstract: A magnetic device and power converter employing the same. In one embodiment, the magnetic device includes a first L-core segment including a first leg and a second leg extending therefrom, and an opposing second L-core segment including a first leg and a second leg extending therefrom. The magnetic device also includes a winding formed around at least one of the first leg and the second leg of the first L-core segment or the second L-core segment.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: June 28, 2016
    Assignee: Power Systems Technologies, Ltd.
    Inventor: Sriram Chandrasekaran
  • Patent number: 9240712
    Abstract: A controller for a power converter includes a current-sense device couplable in series with switched terminals of power switches of interleaved switching regulators and configured to produce a current-sense signal. The controller also includes an error amplifier configured to produce an error signal as a function of a characteristic of the power converter. The controller also includes a duty-cycle controller configured to sample the current-sense signal at mid-points of duty cycles of the power switches and regulate the characteristic as a function of the error signal and the current-sense signal.
    Type: Grant
    Filed: December 13, 2012
    Date of Patent: January 19, 2016
    Assignee: Power Systems Technologies Ltd.
    Inventor: Sriram Chandrasekaran
  • Patent number: 9214264
    Abstract: A magnetic device and power converter employing the same. In one embodiment, the magnetic device includes a first L-core segment including a first leg and a second leg extending therefrom, and an opposing second L-core segment including a first leg and a second leg extending therefrom. The magnetic device also includes a winding formed around at least one of the first leg and the second leg of the first L-core segment or the second L-core segment.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: December 15, 2015
    Assignee: Power systems Technologies, Ltd.
    Inventor: Sriram Chandrasekaran
  • Patent number: 9190898
    Abstract: A controller for a power converter and method of operating the same. In one embodiment, the controller includes an inductor-inductor-capacitor (“LLC”) controller configured to receive an error signal from an error amplifier to control a switching frequency of an LLC stage of the power converter to regulate an output voltage thereof. The controller also includes a power factor correction (“PFC”) controller configured to control a bus voltage produced by a PFC stage of the power converter and provided to the LLC stage so that an average switching frequency thereof is substantially maintained at a desired switching frequency.
    Type: Grant
    Filed: July 6, 2012
    Date of Patent: November 17, 2015
    Assignee: Power Systems Technologies, Ltd
    Inventors: Antony Brinlee, Sriram Chandrasekaran, Steven Malechek
  • Patent number: 9106130
    Abstract: A magnetic device and power converter employing the same. In one embodiment, the magnetic device includes a first L-core segment including a first leg and a second leg extending therefrom, and an opposing second L-core segment including a first leg and a second leg extending therefrom. The magnetic device also includes a winding formed around at least one of the first leg and the second leg of the first L-core segment or the second L-core segment.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: August 11, 2015
    Assignee: Power Systems Technologies, Inc.
    Inventor: Sriram Chandrasekaran
  • Patent number: 9099232
    Abstract: A magnetic device and power converter employing the same. In one embodiment, the magnetic device includes a first L-core segment including a first leg and a second leg extending therefrom, and an opposing second L-core segment including a first leg and a second leg extending therefrom. The magnetic device also includes a winding formed around at least one of the first leg and the second leg of the first L-core segment or the second L-core segment.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: August 4, 2015
    Assignee: Power Systems Technologies Ltd.
    Inventor: Sriram Chandrasekaran
  • Patent number: 9019061
    Abstract: A magnetic device formed with U-shaped core pieces employable in a power converter, and a method of forming the same. In one embodiment, the magnetic device includes a rectilinear core piece formed of a magnetic material, and first and second U-shaped core pieces positioned on the rectilinear core piece. The magnetic device also includes first and second conductive windings formed about the first and second U-shaped core pieces, respectively.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: April 28, 2015
    Assignee: Power Systems Technologies, Ltd.
    Inventor: Sriram Chandrasekaran
  • Publication number: 20140169049
    Abstract: A controller for a power converter and method of operating the same. In one embodiment, the controller includes a current-sense device couplable in series with switched terminals of power switches of interleaved switching regulators and configured to produce a current-sense signal. The controller also includes an error amplifier configured to produce an error signal as a function of a characteristic of the power converter. The controller also includes a duty-cycle controller configured to sample the current-sense signal at mid-points of duty cycles of the power switches and regulate the characteristic as a function of the error signal and the current-sense signal.
    Type: Application
    Filed: December 13, 2012
    Publication date: June 19, 2014
    Applicant: POWER SYSTEMS TECHNOLOGIES, LTD.
    Inventor: Sriram Chandrasekaran
  • Publication number: 20140016369
    Abstract: A magnetic device and power converter employing the same. In one embodiment, the magnetic device includes a first L-core segment including a first leg and a second leg extending therefrom, and an opposing second L-core segment including a first leg and a second leg extending therefrom. The magnetic device also includes a winding formed around at least one of the first leg and the second leg of the first L-core segment or the second L-core segment.
    Type: Application
    Filed: July 16, 2012
    Publication date: January 16, 2014
    Applicant: POWER SYSTEMS TECHNOLOGIES, LTD.
    Inventor: Sriram Chandrasekaran
  • Publication number: 20140016367
    Abstract: A magnetic device and power converter employing the same. In one embodiment, the magnetic device includes a first L-core segment including a first leg and a second leg extending therefrom, and an opposing second L-core segment including a first leg and a second leg extending therefrom. The magnetic device also includes a winding formed around at least one of the first leg and the second leg of the first L-core segment or the second L-core segment.
    Type: Application
    Filed: July 16, 2012
    Publication date: January 16, 2014
    Applicant: POWER SYSTEMS TECHNOLOGIES, LTD.
    Inventor: Sriram Chandrasekaran