Patents by Inventor Yantao Ma

Yantao Ma 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: 7965580
    Abstract: Control signal oscillation filtering circuits, delay-locked loops, clock synchronization methods and devices and systems incorporating control signal oscillation filtering circuits are described. An oscillation filtering circuit includes a first oscillation filter configured to filter oscillations and a majority filter configured to average filter an output of a phase detector and generate in response thereto control signals to an adjustable delay line.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: June 21, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Yantao Ma
  • Publication number: 20110122720
    Abstract: Memory devices and methods are provided for reducing simultaneous switching output noise and power supply noise during burst data write and refresh operations. An embodiment of a memory device according to the present invention includes a first power domain coupled to some of the components of the memory device and a second power domain coupled to different components of the memory device. One or more distributed power domain coupling circuits may be coupled to the first and second power domains. The power domain coupling circuit includes a controller configured to generate an enable signal responsive to control signals, data signals, or any combination thereof. The power domain coupling circuit also includes coupling circuitry coupled to the first and second power domains and coupled to the controller. The coupling circuitry is configured to couple the first and second power domains together responsive to the enable signal.
    Type: Application
    Filed: February 1, 2011
    Publication date: May 26, 2011
    Applicant: Micron Technology, Inc.
    Inventors: Yantao Ma, Todd Merritt
  • Publication number: 20110116301
    Abstract: The present disclosure includes methods, devices, modules, and systems for sensing memory cells using a state machine. One method embodiment includes generating a first sensing reference according to a first output of a state machine. The method includes bifurcating a range of possible programmed levels to which a memory cell can be programmed with the first sensing reference. The method also includes generating a second sensing reference according to a second output of the state machine. The method further includes determining a programmed level of the memory cell with the second generated sensing reference.
    Type: Application
    Filed: January 24, 2011
    Publication date: May 19, 2011
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Yantao Ma, Jun Liu
  • Publication number: 20110109367
    Abstract: Memories, multi-phase clock signal generators, and methods for generating multi-phase duty cycle corrected clock signals are disclosed. For example, one such clock signal generator includes a delay-locked loop having a first multi-tap adjustable delay line configured to delay a reference signal to provide a plurality of clock signals having different phases relative to the reference clock signal. A periodic signal generated by the delay-locked loop is provided to a second multi-tap adjustable delay line as an input clock signal. Clock signals from taps of the second multi-tap adjustable delay line are provided as the multi-phase duty cycle corrected clock signals.
    Type: Application
    Filed: January 14, 2011
    Publication date: May 12, 2011
    Applicant: MICRON TECHNOLOGY, INC.
    Inventor: Yantao Ma
  • Patent number: 7928781
    Abstract: Systems and methods for synchronization of clock signals are disclosed. In a feedback system such as a delay-lock loop circuit, delays to be applied can be determined adaptively based on a phase difference between a reference signal and a clock signal being delayed. Such adaptive decisions can be made during each feedback cycle, thereby making it possible to achieve a phase lock faster and more efficiently. In some embodiments, such adaptive functionality can be incorporated into existing circuits with minimal impact.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: April 19, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Yantao Ma
  • Patent number: 7911245
    Abstract: A multi-phase signal generators and methods for generating multi-phase signals are described. In one embodiment, a clock generator generates quadrature signals including those having 90, 180, 270 and 360 degrees phase difference with a first signal. The rising edge of an intermediate signal is compared with the rising edges of two of the other signals to generate an UP and DN pulse signal, respectively. The UP and DN signals are used to adjust the delay of a delay line producing the signals to synchronize the signals. In some embodiments, a reset signal generator is used to truncate the UP or DN signal pulse.
    Type: Grant
    Filed: October 3, 2008
    Date of Patent: March 22, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Yantao Ma
  • Publication number: 20110058406
    Abstract: The present disclosure includes resistive memory devices and systems having resistive memory cells, as well as methods for operating the resistive memory cells. One memory device embodiment includes at least one resistive memory element, a programming circuit, and a sensing circuit. For example, the programming circuit can include a switch configured to select one of N programming currents for programming the at least one resistive memory element, where each of the N programming currents has a unique combination of current direction and magnitude, with N corresponding to the number of resistance states of the at least one memory element. In one or more embodiments, the sensing circuit can be arranged for sensing of the N resistance states.
    Type: Application
    Filed: November 15, 2010
    Publication date: March 10, 2011
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Yantao Ma, Jun Liu
  • Publication number: 20110050303
    Abstract: Embodiments are described that compensate for a difference in a characteristic (e.g., of performance or operation) of a semiconductor device that is a function of the location of a die in a device. In one embodiment, a clock circuit may generate a clock signal having a timing that varies with the location of a die so that signals are coupled from the die to a substrate at the same time despite differences in the signal propagation time between the substrate and the various die. In other embodiments, for example, differences in the termination impedance or driver drive-strength resulting from differences in the location of a die in a stack may be compensated for. Other embodiments are also disclosed.
    Type: Application
    Filed: August 27, 2009
    Publication date: March 3, 2011
    Applicant: Micron Technology, Inc.
    Inventor: Yantao Ma
  • Patent number: 7894285
    Abstract: Memory devices and methods are provided for reducing simultaneous switching output noise and power supply noise during burst data write and refresh operations. An embodiment of a memory device according to the present invention includes a first power domain coupled to some of the components of the memory device and a second power domain coupled to different components of the memory device. One or more distributed power domain coupling circuits may be coupled to the first and second power domains. The power domain coupling circuit includes a controller configured to generate an enable signal responsive to control signals, data signals, or any combination thereof. The power domain coupling circuit also includes coupling circuitry coupled to the first and second power domains and coupled to the controller. The coupling circuitry is configured to couple the first and second power domains together responsive to the enable signal.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: February 22, 2011
    Assignee: Micron Technology, Inc.
    Inventors: Yantao Ma, Todd Merritt
  • Publication number: 20110025389
    Abstract: Clock circuits, memories and methods for generating a clock signal are described. One such clock circuit includes a delay locked loop (DLL) configured to receive a reference clock signal and generate an output clock signal having an adjustable phase relationship relative to the reference clock signal, and further includes a clock jitter feedback circuit coupled to a clock tree and the DLL. The clock jitter feedback circuit is configured to synchronize a clock jitter feedback signal and a DLL feedback signal that is based on the output clock signal. The clock jitter feedback circuit is further configured to provide the clock jitter feedback signal to the DLL for synchronization with a buffered reference clock signal. The clock jitter feedback signal is based on and generated in response to receiving a distributed output clock signal from the clock tree circuit and the buffered reference signal is based on the reference clock signal.
    Type: Application
    Filed: October 12, 2010
    Publication date: February 3, 2011
    Inventor: Yantao Ma
  • Patent number: 7881100
    Abstract: The present disclosure includes methods, devices, modules, and systems for sensing memory cells using a state machine. One method embodiment includes generating a first sensing reference according to a first output of a state machine. The method includes bifurcating a range of possible programmed levels to which a memory cell can be programmed with the first sensing reference. The method also includes generating a second sensing reference according to a second output of the state machine. The method further includes determining a programmed level of the memory cell with the second generated sensing reference.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: February 1, 2011
    Assignee: Micron Technology, Inc.
    Inventors: Yantao Ma, Jun Liu
  • Patent number: 7872924
    Abstract: Memories, multi-phase clock signal generators, and methods for generating multi-phase duty cycle corrected clock signals are disclosed. For example, one such clock signal generator includes a delay-locked loop having a first multi-tap adjustable delay line configured to delay a reference signal to provide a plurality of clock signals having different phases relative to the reference clock signal. A periodic signal generated by the delay-locked loop is provided to a second multi-tap adjustable delay line as an input clock signal. Clock signals from taps of the second multi-tap adjustable delay line are provided as the multi-phase duty cycle corrected clock signals.
    Type: Grant
    Filed: October 28, 2008
    Date of Patent: January 18, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Yantao Ma
  • Publication number: 20110001528
    Abstract: Apparatus, systems, and methods are disclosed that operate to generate a periodic output signal from a periodic input signal, obtain a plurality of samples of a phase difference between the output signal and the input signal, and to adjust a phase of the output signal based on the samples of the phase difference. Additional apparatus, systems, and methods are disclosed.
    Type: Application
    Filed: September 10, 2010
    Publication date: January 6, 2011
    Inventors: Yantao Ma, Jeffrey P. Wright, Dong Pan
  • Patent number: 7835173
    Abstract: The present disclosure includes resistive memory devices and systems having resistive memory cells, as well as methods for operating the resistive memory cells. One memory device embodiment includes at least one resistive memory element, a programming circuit, and a sensing circuit. For example, the programming circuit can include a switch configured to select one of N programming currents for programming the at least one resistive memory element, where each of the N programming currents has a unique combination of current direction and magnitude, with N corresponding to the number of resistance states of the at least one memory element. In one or more embodiments, the sensing circuit can be arranged for sensing of the N resistance states.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: November 16, 2010
    Assignee: Micron Technology, Inc.
    Inventors: Yantao Ma, Jun Liu
  • Patent number: 7825711
    Abstract: Clock circuits, memories and methods for generating a clock signal are described. One such clock circuit includes a delay locked loop (DLL) configured to receive a reference clock signal and generate an output clock signal having an adjustable phase relationship relative to the reference clock signal, and further includes a clock jitter feedback circuit coupled to a clock tree and the DLL. The clock jitter feedback circuit is configured to synchronize a clock jitter feedback signal and a DLL feedback signal that is based on the output clock signal. The clock jitter feedback circuit is further configured to provide the clock jitter feedback signal to the DLL for synchronization with a buffered reference clock signal. The clock jitter feedback signal is based on and generated in response to receiving a distributed output clock signal from the clock tree circuit and the buffered reference signal is based on the reference clock signal.
    Type: Grant
    Filed: April 1, 2009
    Date of Patent: November 2, 2010
    Assignee: Micron Technology, Inc.
    Inventor: Yantao Ma
  • Publication number: 20100253404
    Abstract: Clock circuits, memories and methods for generating a clock signal are described. One such clock circuit includes a delay locked loop (DLL) configured to receive a reference clock signal and generate an output clock signal having an adjustable phase relationship relative to the reference clock signal, and further includes a clock jitter feedback circuit coupled to a clock tree and the DLL. The clock jitter feedback circuit is configured to synchronize a clock jitter feedback signal and a DLL feedback signal that is based on the output clock signal. The clock jitter feedback circuit is further configured to provide the clock jitter feedback signal to the DLL for synchronization with a buffered reference clock signal. The clock jitter feedback signal is based on and generated in response to receiving a distributed output clock signal from the clock tree circuit and the buffered reference signal is based on the reference clock signal.
    Type: Application
    Filed: April 1, 2009
    Publication date: October 7, 2010
    Inventor: Yantao Ma
  • Patent number: 7804344
    Abstract: Apparatus, systems, and methods are disclosed that operate to generate a periodic output signal from a periodic input signal, obtain a plurality of samples of a phase difference between the output signal and the input signal, and to adjust a phase of the output signal based on the samples of the phase difference. Additional apparatus, systems, and methods are disclosed.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: September 28, 2010
    Assignee: Micron Technology, Inc.
    Inventors: Yantao Ma, Jeffrey P. Wright, Dong Pan
  • Publication number: 20100239234
    Abstract: Apparatus, systems, and methods are disclosed that operate to delay a periodic input signal in one or more delay elements of a group of delay elements to generate a periodic output signal and to vary a power supply to the delay elements. Additional apparatus, systems, and methods are disclosed.
    Type: Application
    Filed: June 4, 2010
    Publication date: September 23, 2010
    Inventor: Yantao Ma
  • Publication number: 20100201415
    Abstract: A circuit, delay-locked loop, memory device, system and method of synchronizing a clock are described. A circuit generally includes a delay line configured to delay an external clock signal to produce a substantially in-phase output clock signal, a main loop configured to control delay through the delay line, and a secondary loop configured to adjust delay through the main loop. The clock synchronization method generally includes adjusting a delay along a delay line in response to a first phase difference between an input clock to the delay line and a shared clock signal delayed by a shared dynamic I/O model of an output driver. The method further includes adjusting the shared dynamic I/O model in response to a second phase difference between an output clock signal and the shared clock signal.
    Type: Application
    Filed: April 20, 2010
    Publication date: August 12, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventor: Yantao Ma
  • Patent number: 7737741
    Abstract: Apparatus, systems, and methods are disclosed that operate to delay a periodic input signal in one or more delay elements of a group of delay elements to generate a periodic output signal and to vary a power supply to the delay elements. Additional apparatus, systems, and methods are disclosed.
    Type: Grant
    Filed: September 20, 2007
    Date of Patent: June 15, 2010
    Assignee: Micron Technology, Inc.
    Inventor: Yantao Ma