Patents by Inventor Raja J. Prabhu

Raja J. Prabhu 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: 9025791
    Abstract: A device implementing a scheme for reduction of pop-up noise is disclosed. The device comprises an audio sub-system (100) having an integrator (112) for amplifying an input signal (133) and a modulation circuit (114) including one or more comparators. The audio subsystem (100) is further provided with a feedback loop (142) across the integrator (112) and the modulation circuit (114) to calibrate an offsets outputs of the integrator (112) and the modulation circuit (114). The feedback loop (142) includes an integrator-offset loop (202) across the integrator (112) to calibrate an offset (136) in the output of the integrator (112), and an offset calibration loop (302) across the modulation circuit (114) to calibrate an offset (140) in the output of the modulation circuit (114).
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: May 5, 2015
    Assignee: ST-Ericsson SA
    Inventors: Ankit Seedher, Raja J. Prabhu, Shyam S. Somayajula
  • Patent number: 8841950
    Abstract: A device and a method for implementing pulse width modulation for switching amplifiers (120) is described herein. In one embodiment, the device includes a sampling signal generator (202) to generate a sampling signal (208) and a modulation unit (102) operatively coupled to the sampling signal generator (202). The modulation unit (102) generates differential pulse width modulated waveforms based on the sampling signal (208) and differential input signals (220-1 and 220-2) such that at least one differential pulse width modulated waveform has a duty cycle equivalent to a pre-determined non-zero minimum pulse width at all values of the differential input signals (220-1 and 220-2).
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: September 23, 2014
    Assignee: Ericsson Modems SA
    Inventors: Shyam S. Somayajula, Ankit Seedher, Raja J. Prabhu
  • Publication number: 20120274399
    Abstract: A device implementing a scheme for reduction of pop-up noise is disclosed. The device comprises an audio sub-system (100) having an integrator (112) for amplifying an input signal (133) and a modulation circuit (114) including one or more comparators. The audio subsystem (100) is further provided with a feedback loop (142) across the integrator (112) and the modulation circuit (114) to calibrate an offsets outputs of the integrator (112) and the modulation circuit (114). The feedback loop (142) includes an integrator-offset loop (202) across the integrator (112) to calibrate an offset (136) in the output of the integrator (112), and an offset calibration loop (302) across the modulation circuit (114) to calibrate an offset (140) in the output of the modulation circuit (114).
    Type: Application
    Filed: November 30, 2009
    Publication date: November 1, 2012
    Inventors: Ankit Seedher, Raja J. Prabhu, Shyam S. Somayajula
  • Publication number: 20120249202
    Abstract: A device and a method for implementing pulse width modulation for switching amplifiers (120) is described herein. In one embodiment, the device includes a sampling signal generator (202) to generate a sampling signal (208) and a modulation unit (102) operatively coupled to the sampling signal generator (202). The modulation unit (102) generates differential pulse width modulated waveforms based on the sampling signal (208) and differential input signals (220-1 and 220-2) such that at least one differential pulse width modulated waveform has a duty cycle equivalent to a pre-determined non-zero minimum pulse width at all values of the differential input signals (220-1 and 220-2).
    Type: Application
    Filed: October 8, 2010
    Publication date: October 4, 2012
    Inventors: Shyam Somayajula, Ankit Seedher, Raja J. Prabhu