Patents by Inventor Krishna N. H. Sri

Krishna N. H. Sri 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).

  • Publication number: 20230251699
    Abstract: A test and measurement instrument includes components and methods for measuring noise at an output of a power supply, measuring jitter of a serial data signal produced by a data generating circuit coupled to the power supply and correlating the noise measured from the power supply to the jitter of the serial data signal. The correlation may be performed in the frequency domain. Spectral plots of the measured noise and the measured jitter may be generated and presented to the user.
    Type: Application
    Filed: February 3, 2023
    Publication date: August 10, 2023
    Applicant: Tektronix, Inc.
    Inventors: Madhusudan Acharya, Yogesh M. Pai, Krishna N H Sri, Anthony B. Ambrose, Blair Battye, Dallas J. Mohler
  • Publication number: 20230133047
    Abstract: A test and measurement instrument has a user interface, one or more probes to connect to a device under test (DUT), and one or more processors configured to execute code to cause the one or more processors to: receive waveform data from the DUT after activation of the DUT by application of power from a power supply, and application of at least a first and second pulse from a source instrument, locate one or more reverse recovery regions in the waveform data, determine a reverse recovery time for the DUT from the reverse recovery region, and display a reverse recovery plot of the one or more reverse recovery regions on the user interface, the reverse recovery plot being automatically configured to display one or more of the reverse recovery regions, and including at least one characteristic for the one or more reverser recovery regions annotated on the reverse recovery plot.
    Type: Application
    Filed: October 28, 2022
    Publication date: May 4, 2023
    Applicant: Tektronix, Inc.
    Inventors: Vivek Shivaram, Niranjan R Hegde, Parjanya Adiga, Krishna N H Sri, Tsuyoshi Miyazaki, Yogesh M. Pai, Venkatraj Melinamane
  • Publication number: 20230133743
    Abstract: A test and measurement instrument has a user interface, one or more probes to allow the instrument to connect to a device under test (DUT), and one or more processors configured to execute code to cause the one or more processors to: receive one or more user inputs through the user interface, at least one of the user inputs to identify at least one analysis to be performed on the DUT, receive waveform data from the DUT when the DUT is activated by application of power from a power supply, and application of one of a first and second pulse or multiple pulses from a source instrument, perform the at least one analysis on the waveform data, and display the waveform data and analysis on the user interface.
    Type: Application
    Filed: October 28, 2022
    Publication date: May 4, 2023
    Applicant: Tektronix, Inc.
    Inventors: Vivek Shivaram, Niranjan R Hegde, Parjanya Adiga, Krishna N H Sri, Tsuyoshi Miyazaki, Yogesh M. Pai, Venkatraj Melinamane
  • Publication number: 20220413051
    Abstract: A test and measurement instrument includes one or more sensors configured to measure a mechanical position of a synchronous machine driven by analog three-phase signals, a converter to determine an instantaneous electrical angle from the measured mechanical position, a transform configured to generate DQ0 signals based on the instantaneous electrical angle, and a vector generator structured to produce a resultant vector from the DQ0 signals. Methods are also described.
    Type: Application
    Filed: June 24, 2022
    Publication date: December 29, 2022
    Applicant: Tektronix, Inc.
    Inventors: Parjanya Adiga, Niranjan R. Hegde, Krishna N H. Sri, Gary J. Waldo, Yogesh M. Pai
  • Patent number: 11275131
    Abstract: A test and measurement instrument, including at least one port configured to receive a signal from a device under test (DUT), the signal including a current signal acquired across a magnetic core of the DUT and a voltage signal acquired across the magnetic core of the DUT, and one or more processors. The one or more processors are configured to determine a hysteresis loop based on the current signal and the voltage signal, determine a magnetic flux of the magnetic core based on the voltage signal and the current signal for a number of sample points for each cycle, and determine a maximum magnetic flux for all cycles and a hysteresis loop cycle that corresponds to the maximum magnetic flux. A display configured to display at least one of the hysteresis loop, the signal received from the DUT, and the hysteresis loop cycle that corresponds to the maximum magnetic flux.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: March 15, 2022
    Assignee: Tektronix, Inc.
    Inventors: U N Vasudev, Suman Babu Alaparthi, Niranjan R Hegde, Krishna N H Sri
  • Patent number: 11181581
    Abstract: The disclosed technology relates to a method and apparatus for graphically displaying a switching cycle of a switching device. A switching voltage and a switching current are acquired for a device under test via a voltage probe and a current probe, respectively, for a plurality of switching cycles of the device under test. The switching current versus the switching voltage is plotted on a current versus voltage plot as a curve for each of the switching cycles. Each of the curves on the current versus voltage plot overlap each other and are displayed to a user.
    Type: Grant
    Filed: April 21, 2014
    Date of Patent: November 23, 2021
    Assignee: TEKTRONIX, INC.
    Inventors: Krishna N H Sri, Gajendra Kumar Patro, Abhinav Bal, Gurushiddappa M N
  • Publication number: 20210358685
    Abstract: A test and measurement instrument for determining magnetic core losses of a device under test during in circuit operation. The test and measurement instrument receives a primary current signal from a primary winding of a device under test and receives a primary voltage signal measured across a magnetic core of the device under test. Based on the primary electric current signal and the primary voltage signal, the test and measurement instrument determines a magnetic loss of the device under test. In some examples, the test and measurement instrument can use primary and secondary voltage and current inputs to determine the magnetic loss of the device under test. The magnetic loss of the device under test can be displayed on a display of the test and measurement instrument. The magnetic loss can include a total magnetic loss, a hysteresis loss, a copper loss, and/or other losses.
    Type: Application
    Filed: May 7, 2021
    Publication date: November 18, 2021
    Applicant: Tektronix, Inc.
    Inventors: Shubha B, Niranjan R Hegde, Yogesh M Pai, Gajendra Kumar Patro, Krishna N H Sri
  • Patent number: 10895612
    Abstract: A test and measurement instrument, comprising at least one port configured to receive a signal from a device under test; a user interface configured to receive a user input, the user input indicating magnetic properties of a magnetic material of the device under test, and one or more processors. The one or more processors are configured to generate a hysteresis loop mask based on the magnetic properties of the magnetic material, determine whether the signal received from the device under test violates the hysteresis loop mask, and generate an alert when the signal received from the device under test violates the hysteresis loop mask. The test and measurement instrument may also include a display configured to display the hysteresis loop mask, the signal received from the device under test, and/or the alert.
    Type: Grant
    Filed: October 15, 2018
    Date of Patent: January 19, 2021
    Assignee: Tektronix, Inc.
    Inventors: U N Vasudev, Gajendra Kumar Patro, Krishna N H Sri
  • Publication number: 20210013818
    Abstract: A test and measurement device includes an interface configured to acquire analog three-phase signals from a device under test, and a processor programmed to execute instructions that cause the processor to perform a direct-quadrature-zero, DQ0, transformation and produce DQ0 signals based on the analog three-phase signals, and measure performance of the device under test based on the DQ0 signals. A method includes acquiring three-phase signals from a device under test, performing a direct-quadrature-zero, DQ0, transformation on the three-phase signals to produce DQ0 signals, and using the DQ0 signals to measure performance of the device under test.
    Type: Application
    Filed: July 6, 2020
    Publication date: January 14, 2021
    Applicant: Tektronix, Inc.
    Inventors: U N Vasudev, Krishna N H Sri, Vempati L. Bharghavi
  • Publication number: 20200116805
    Abstract: A test and measurement instrument, comprising at least one port configured to receive a signal from a device under test; a user interface configured to receive a user input, the user input indicating magnetic properties of a magnetic material of the device under test, and one or more processors. The one or more processors are configured to generate a hysteresis loop mask based on the magnetic properties of the magnetic material, determine whether the signal received from the device under test violates the hysteresis loop mask, and generate an alert when the signal received from the device under test violates the hysteresis loop mask. The test and measurement instrument may also include a display configured to display the hysteresis loop mask, the signal received from the device under test, and/or the alert.
    Type: Application
    Filed: October 15, 2018
    Publication date: April 16, 2020
    Applicant: Tektronix, Inc.
    Inventors: U N Vasudev, Gajendra Kumar Patro, Krishna N H Sri
  • Patent number: 9618965
    Abstract: A system for dynamically calibrating operational parameters of a Device Under Test (DUT) includes a signal generator for generating a data pattern, a DUT structured to generate a clock signal, an oscilloscope structured to measure margins of the generated clock signal compared to an eye-diagram produced on the oscilloscope from the data pattern, and a calibration unit. The calibration unit can produce a candidate a jitter value for the signal generator, receive a determination from the oscilloscope whether the data pattern generated with the candidate jitter value causes the DUT to produce the generated clock signal within a pre-determined tolerance level, and modify the jitter value accordingly. The calibration unit may also be further structured to generate voltage swing values.
    Type: Grant
    Filed: July 30, 2015
    Date of Patent: April 11, 2017
    Assignee: Tektronix, Inc.
    Inventors: Ganesh K. Kumar, Krishna N H Sri, Madhusudhan Acharya, Kamlesh Mishra
  • Publication number: 20160334833
    Abstract: A system for dynamically calibrating operational parameters of a Device Under Test (DUT) includes a signal generator for generating a data pattern, a DUT structured to generate a clock signal, an oscilloscope structured to measure margins of the generated clock signal compared to an eye-diagram produced on the oscilloscope from the data pattern, and a calibration unit. The calibration unit can produce a candidate a jitter value for the signal generator, receive a determination from the oscilloscope whether the data pattern generated with the candidate jitter value causes the DUT to produce the generated clock signal within a pre-determined tolerance level, and modify the jitter value accordingly. The calibration unit may also be further structured to generate voltage swing values.
    Type: Application
    Filed: July 30, 2015
    Publication date: November 17, 2016
    Inventors: Ganesh K. Kumar, Krishna N H Sri, Madhusudhan Acharya, Kamlesh Mishra
  • Publication number: 20150032393
    Abstract: The disclosed technology relates to a method and apparatus for graphically displaying a switching cycle of a switching device. A switching voltage and a switching current are acquired for a device under test via a voltage probe and a current probe, respectively, for a plurality of switching cycles of the device under test. The switching current versus the switching voltage is plotted on a current versus voltage plot as a curve for each of the switching cycles. Each of the curves on the current versus voltage plot overlap each other and are displayed to a user.
    Type: Application
    Filed: April 21, 2014
    Publication date: January 29, 2015
    Applicant: TEKTRONIX, INC.
    Inventors: KRISHNA N H SRI, GAJENDRA KUMAR PATRO, ABHINAV BAL, GURUSHIDDAPPA M N
  • Patent number: 8670947
    Abstract: Embodiments of the invention provide a system and method to measure and represent the measured value of a limit in terms of another measurement, such as clock values or cycles of the system. The system can include, for example, a test and measurement instrument such as an oscilloscope. In another embodiment of the present invention, slew rate de-rated values may be automatically determined through the use of configurable lookup tables.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: March 11, 2014
    Assignee: Tektronix, Inc.
    Inventors: G. R. N. Prasanth, Pechluck Pongched, Raghavendran N., Mark L. Guenther, Krishna N. H. Sri, Manisha D. Ajgaonkar, Anuradha V.
  • Publication number: 20110119688
    Abstract: Embodiments of the invention provide a system and method to measure and represent the measured value of a limit in terms of another measurement, such as clock values or cycles of the system. The system can include, for example, a test and measurement instrument such as an oscilloscope. In another embodiment of the present invention, slew rate de-rated values may be automatically determined through the use of configurable lookup tables.
    Type: Application
    Filed: April 30, 2010
    Publication date: May 19, 2011
    Applicant: TEKTRONIX, INC.
    Inventors: G R N Prasanth, Pechluck Pongched, Raghavendran N, Mark L. Guenther, Krishna N. H. Sri, Manisha D. Ajgaonkar, Anuradha V
  • Publication number: 20080297170
    Abstract: A system, apparatus, and method for dynamic measurement of inductance trend of a motor are disclosed. In one of the embodiment herein the system is configured to acquire inputs from the DUT using a Trigger system, a horizontal subsystem and the programming unit. The system is also configured to process such information for dynamic analysis and representation on an interface provided in the system based on different step sizes.
    Type: Application
    Filed: May 21, 2008
    Publication date: December 4, 2008
    Applicant: TEKTRONIX, INC.
    Inventors: Krishna N. H. Sri, Mukesh Soni, Narasimha Murthy K.