Patents by Inventor Mahmood Khayatzadeh

Mahmood Khayatzadeh 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: 20230251683
    Abstract: A timing margin sensor circuit includes one or more time-to-digital converters (TDCs), a predictor, and a translation circuit. The TDC(s) measure(s) progress of a clock signal through one or more chains of delay stages. The progress depends on sense conditions acting upon the delay chain, such as the supply voltage and the temperature. The predictor receives the measured progress. If the delay chain becomes slower, the predictor extrapolates a predicted progress value. If the delay chain becomes faster, the predictor outputs the actual progress value. The translator translates the predictor output value to sense information that can be used in a clock stretcher circuit. The timing margin sensor may further have an averager/selector to average or select from the results of multiple TDCs. The timing margin sensor may further have a calibrator to compensate for nominal sense conditions, and one or more tunable delays circuits.
    Type: Application
    Filed: January 31, 2023
    Publication date: August 10, 2023
    Applicant: SambaNova Systems, Inc.
    Inventors: Mahmood KHAYATZADEH, Satyajit SARKAR, Jinuk SHIN
  • Patent number: 11334109
    Abstract: A clock stretcher includes a delay line, a control unit, and a combiner. The delay line outputs a series of delayed phases of an input clock. The control circuit is clocked by the input clock. It outputs a series of delayed phase enable signals. The combiner circuit receives the delayed phases from the delay line and the delayed phase enable signals from the control circuit, and outputs a modified clock. The control circuit determines if stretching has started, if wraparound must occur, and if a next phase must be enabled. The combiner retimes a delayed phase enable signal for a first delayed phase using a flipflop clocked by a second delayed phase to generate a retimed phase enable signal. The combiner uses the retimed phase enable signal to pass a pulse of the first delayed phase to the output as a pulse of the modified clock.
    Type: Grant
    Filed: August 18, 2021
    Date of Patent: May 17, 2022
    Assignee: SambaNova Systems, Inc.
    Inventors: Fahim ur Rahman, Mahmood Khayatzadeh, Zuxu Qin, Jin-uk Shin
  • Patent number: 11323124
    Abstract: A clock stretcher includes a DLL that derives delayed versions of an input clock signal, and a combiner that cyclically selects the delayed versions to generate a modified clock signal. The DLL has a phase error because of its finite bandwidth. The clock stretcher measures the phase error and corrects for a glitch in the modified clock signal by using the phase error when phase selection wraparound occurs. The clock stretcher may operate from a power supply that has droops, without intervening voltage regulation.
    Type: Grant
    Filed: June 3, 2021
    Date of Patent: May 3, 2022
    Assignee: SambaNova Systems, Inc.
    Inventors: Fahim ur Rahman, Mahmood Khayatzadeh, Zuxu Qin, Jin-Uk Shin
  • Patent number: 11290114
    Abstract: A clock stretcher includes a DLL that derives delayed versions of an input clock signal. The clock stretcher has passive and stretching modes. It operates from a sensed power supply without intervening voltage regulation. In passive mode, it forwards input clock pulses to the clock stretcher output. The input clock pulses are delayed by fewer than 10 DLL delay line delay stages. In stretching mode, a combiner cyclically selects the delayed versions of the input clock signal to generate a modified clock signal. The combiner uses a hop code, dependent on a sensed condition, to determine the step size for the cyclical selection. To enter passive mode, the clock stretcher tests if a passive mode entry threshold is met. The threshold includes two conditions: the hop code must be zero, and phase selection must have reached a wraparound point that may have been corrected for a delay line offset.
    Type: Grant
    Filed: June 3, 2021
    Date of Patent: March 29, 2022
    Assignee: SAMBANOVA SYSTEMS, INC.
    Inventors: Fahim ur Rahman, Mahmood Khayatzadeh, Jin-Uk Shin
  • Patent number: 10056121
    Abstract: Various implementations described herein may refer to and may be directed to circuitry for an integrated circuit using topology configurations. For instance, in one implementation, such circuitry may include a memory array having a plurality of memory cells. Such circuitry may also include one or more reconfigurable sense amplifier devices coupled to the memory array and configured to amplify differential voltage levels received from the memory array. The reconfigurable sense amplifier devices may include a plurality of sense amplifier circuits configured to be arranged in one of a plurality of topology configurations, where the topology configurations include a parallel configuration and a cross parallel configuration. The reconfigurable sense amplifier devices may also include one or more switches configured to set the plurality of sense amplifier circuits into the plurality of topological configurations based on one or more control bits.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: August 21, 2018
    Assignees: ARM Limited, The Regents of the University of Michigan
    Inventors: Mahmood Khayatzadeh, Massimo Bruno Alioto, David Theodore Blaauw, Dennis Michael Chen Sylvester, Fakhruddin Ali Bohra
  • Publication number: 20170178700
    Abstract: Various implementations described herein may refer to and may be directed to circuitry for an integrated circuit using topology configurations. For instance, in one implementation, such circuitry may include a memory array having a plurality of memory cells. Such circuitry may also include one or more reconfigurable sense amplifier devices coupled to the memory array and configured to amplify differential voltage levels received from the memory array. The reconfigurable sense amplifier devices may include a plurality of sense amplifier circuits configured to be arranged in one of a plurality of topology configurations, where the topology configurations include a parallel configuration and a cross parallel configuration. The reconfigurable sense amplifier devices may also include one or more switches configured to set the plurality of sense amplifier circuits into the plurality of topological configurations based on one or more control bits.
    Type: Application
    Filed: March 6, 2017
    Publication date: June 22, 2017
    Inventors: Mahmood Khayatzadeh, Massimo Bruno Alioto, David Theodore Blaauw, Dennis Michael Chen Sylvester, Fakhruddin Ali Bohra
  • Patent number: 9589601
    Abstract: Various implementations described herein may refer to and may be directed to circuitry for an integrated circuit using topology configurations. For instance, in one implementation, such circuitry may include a memory array having a plurality of memory cells. Such circuitry may also include one or more reconfigurable sense amplifier devices coupled to the memory array and configured to amplify differential voltage levels received from the memory array. The reconfigurable sense amplifier devices may include a plurality of sense amplifier circuits configured to be arranged in one of a plurality of topology configurations, where the topology configurations include a parallel configuration and a cross parallel configuration. The reconfigurable sense amplifier devices may also include one or more switches configured to set the plurality of sense amplifier circuits into the plurality of topological configurations based on one or more control bits.
    Type: Grant
    Filed: March 16, 2015
    Date of Patent: March 7, 2017
    Assignees: ARM Limited, The Regents of the University of Michigan
    Inventors: Mahmood Khayatzadeh, Massimo Bruno Alioto, David Blaauw, Dennis Michael Chen Sylvester, Fakhruddin Ali Bohra
  • Publication number: 20160276000
    Abstract: Various implementations described herein may refer to and may be directed to circuitry for an integrated circuit using topology configurations. For instance, in one implementation, such circuitry may include a memory array having a plurality of memory cells. Such circuitry may also include one or more reconfigurable sense amplifier devices coupled to the memory array and configured to amplify differential voltage levels received from the memory array. The reconfigurable sense amplifier devices may include a plurality of sense amplifier circuits configured to be arranged in one of a plurality of topology configurations, where the topology configurations include a parallel configuration and a cross parallel configuration. The reconfigurable sense amplifier devices may also include one or more switches configured to set the plurality of sense amplifier circuits into the plurality of topological configurations based on one or more control bits.
    Type: Application
    Filed: March 16, 2015
    Publication date: September 22, 2016
    Inventors: Mahmood Khayatzadeh, Massimo Bruno Alioto, David Blaauw, Dennis Michael Chen Sylvester, Fakhruddin Ali Bohra