Patents by Inventor Shahrzad Naraghi

Shahrzad Naraghi 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: 9590574
    Abstract: An audio switching power amplifier having an output with controlled-slope transitions maintains efficiency while avoiding uncontrolled non-overlap intervals during switching transitions. A pair of transistors forming a half-bridge that supplies an output signal at an output terminal of the amplifier are operated so that neither transistor is fully on during an overlap time period. A current source provides an output current to the output terminal during the non-overlap time period to control the output voltage while changing the transistor that conducts the output current from a first one of the pair of transistors to a second one of the pair of transistors. The current source may be provided by operation of one of the transistors in a current source configuration. The voltage of a gate of one of the transistors can be compared with a threshold to provide an indication of the current.
    Type: Grant
    Filed: February 10, 2014
    Date of Patent: March 7, 2017
    Assignee: CIRRUS LOGIC, INC.
    Inventors: Shahrzad Naraghi, Johann Gaboriau, John L. Melanson
  • Patent number: 8841894
    Abstract: An audio switching power amplifier having an output with controlled-slope transitions maintains efficiency while avoiding uncontrolled non-overlap intervals during switching transitions. A pair of transistors forming a half-bridge that supplies an output signal at an output terminal of the amplifier are operated so that neither transistor is fully on during an overlap time period. A current source provides an output current to the output terminal during the non-overlap time period to control the output voltage while changing the transistor that conducts the output current from a first one of the pair of transistors to a second one of the pair of transistors. The current source may be provided by operation of one of the transistors in a current source configuration. The voltage of a gate of one of the transistors can be compared with a threshold to provide an indication of the current.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: September 23, 2014
    Assignee: Cirrus Logic, Inc.
    Inventors: Shahrzad Naraghi, Johann Gaboriau, John L. Melanson
  • Patent number: 8294525
    Abstract: Apparatuses and methods are provided relating to a voltage controlled oscillator (VCO) based on current starved inverting delay stages; wherein in each stage a PMOS transistor as header and an NMOS transistor as footer are used with their gate-to-source voltages always equal to analog control voltage. The analog control voltage is also used as the supply voltage of the oscillator. An exemplary apparatus includes a VCO of n stages, where n is an odd number and where each stage includes a current starved inverter where the analog control voltage is also used as the supply voltage of each delay stage.
    Type: Grant
    Filed: June 18, 2010
    Date of Patent: October 23, 2012
    Assignee: International Business Machines Corporation
    Inventors: John Francis Bulzacchelli, Zeynep Toprak Deniz, Daniel Joseph Friedman, Shahrzad Naraghi, Alexander V Rylyakov
  • Publication number: 20110309888
    Abstract: Apparatuses and methods are provided relating to a voltage controlled oscillator (VCO) based on current starved inverting delay stages; wherein in each stage a PMOS transistor as header and an NMOS transistor as footer are used with their gate-to-source voltages always equal to analog control voltage. The analog control voltage is also used as the supply voltage of the oscillator. An exemplary apparatus includes a VCO of n stages, where n is an odd number and where each stage includes a current starved inverter where the analog control voltage is also used as the supply voltage of each delay stage.
    Type: Application
    Filed: June 18, 2010
    Publication date: December 22, 2011
    Applicant: International Business Machines Corporation
    Inventors: John F. BULZACCHELLI, Zeynep Toprak DENIZ, Daniel Joseph FRIEDMAN, Shahrzad NARAGHI, Alexander V. RYLYAKOV
  • Patent number: 7893861
    Abstract: Apparatus and methods are provided relating to time-to-digital based analog-to-digital converter. An apparatus includes a time-to-digital converter based analog-to-digital converter for generating a first signal and a second signal having a timing relationship between a rising edge of the first signal and a rising edge of the second signal based on a sampled input analog voltage level, and converting the timing relationship into a corresponding time-to-digital representation. The time-to-digital representation is obtained without any voltage comparison and current comparison.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: February 22, 2011
    Assignee: International Business Machines Corporation
    Inventors: John F. Bulzacchelli, Daniel J. Friedman, Shahrzad Naraghi, Sergey V. Rylov, Alexander V. Rylyakov, Zeynep Toprak-Deniz
  • Publication number: 20100328130
    Abstract: Apparatus and methods are provided relating to time-to-digital based analog-to-digital converter. An apparatus includes a time-to-digital converter based analog-to-digital converter for generating a first signal and a second signal having a timing relationship between a rising edge of the first signal and a rising edge of the second signal based on a sampled input analog voltage level, and converting the timing relationship into a corresponding time-to-digital representation. The time-to-digital representation is obtained without any voltage comparison and current comparison.
    Type: Application
    Filed: June 30, 2009
    Publication date: December 30, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: John F. Bulzacchelli, Daniel J. Friedman, Shahrzad Naraghi, Sergey V. Rylov, Alexander V. Rylyakov, Zeynep Toprak-Deniz