Patents by Inventor Kyung Suk Oh

Kyung Suk Oh 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: 9842181
    Abstract: The present disclosure relates to an innovative method of assigning signals to general-purpose input/output pads of an integrated circuit chip. An inductance matrix for the input/output pads is obtained. A candidate assignment is made of a differential signal to a pair of the input/output pads, and a differential mutual inductance is determined for each open pad location in relation to the pair of input/output pads. Single-ended signals are assigned to open pad locations having the lowest differential mutual inductances. The jitter contribution due to each assigned single-ended signal is computed, and a total jitter is updated. In a first embodiment, said assigning, computing and updating steps are repeated until the total jitter exceeds a total jitter budget. In a second embodiment, said assigning, computing and updating steps are repeated until a number of assigned single-ended signals is equal to a target number. Other embodiments and features are also disclosed.
    Type: Grant
    Filed: May 24, 2016
    Date of Patent: December 12, 2017
    Assignee: Altera Corporation
    Inventors: Kyung Suk Oh, Yee Huan Yew, Chee Cheong Tan, Mei See Chin, Wai Ling Lee, Loke Yip Foo, Chooi Ian Loh, Hui Lee Teng
  • Patent number: 9836428
    Abstract: A memory controller and/or memory device control termination of a communication link in order to achieve power savings while reducing or eliminating unwanted reflections in the channel. Following transmission of data over the communication channel, termination is left enabled for a programmable time period beginning immediately following completion of the transmission. The time period is sufficiently long to allow the unwanted reflections to be absorbed by the termination. Following the time period, the termination is disabled for power savings.
    Type: Grant
    Filed: July 17, 2013
    Date of Patent: December 5, 2017
    Assignee: Rambus Inc.
    Inventors: Kyung Suk Oh, Pravin Kumar Venkatesan, Yohan Usthavia Frans
  • Publication number: 20170338979
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: August 7, 2017
    Publication date: November 23, 2017
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Publication number: 20170331477
    Abstract: A memory control component outputs a memory write command to a memory IC and also outputs write data to be received via data inputs of the memory IC. Prior to reception of the write data within the memory IC, the memory control component asserts a termination control signal that causes the memory IC to apply to the data inputs a first on-die termination impedance during reception of the write data followed by a second on-die termination impedance after the write data has been received. The memory control component deasserts the termination control signal to cause the memory IC to apply no termination impedance to the data inputs.
    Type: Application
    Filed: April 28, 2017
    Publication date: November 16, 2017
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Patent number: 9818471
    Abstract: A method of measuring duty-cycle distortion in a signal (e.g., flowing between an operating circuit and a memory circuit), where the signal has a known period, the signal being measured is in a first state during a first portion of the period, and is in a different state during a second portion of the period, includes advancing or retarding the signal until an edge of the signal intersects an edge of the other signal. From the amount of the advancing or retarding, the duty cycle and the magnitude of duty-cycle distortion are determined. This may be used to control correction of the duty-cycle distortion. An interpolator circuit may be used to advance or retard the signal. A processor may be used to keep track of the amount of advancing or retarding, to determine the duration of the duty cycle, and control correction of the duty-cycle distortion.
    Type: Grant
    Filed: September 14, 2016
    Date of Patent: November 14, 2017
    Assignee: Altera Corporation
    Inventors: Kyung Suk Oh, Sean Shau-Tu Lu
  • Patent number: 9748934
    Abstract: Systems and methods for reducing jitter due to power supply noise in an integrated circuit by drawing additional current. The additional current causes the total current to generally have a frequency higher than a resonant frequency of the integrated circuit and/or a power distribution network of the integrated circuit. A power distribution network may supply power to components of an integrated circuit, and data driver circuitry may draw first current to drive a serial data signal generated from a parallel data signal. Compensation circuitry may receive the parallel data signal and draw second current at times when the compensation circuitry determines data driver circuitry is not drawing the first current based on the parallel data signal, thereby causing a net of the first and second current to be higher than a resonant frequency range of the integrated circuit device and/or a component of the integrated circuit device.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: August 29, 2017
    Assignee: Altera Corporation
    Inventors: Kyung Suk Oh, Yujeong Shim, Yanjing Ke, Tim Tri Hoang, Hae-Chang Lee
  • Patent number: 9734879
    Abstract: A memory device comprising a programmable command-and-address (CA) interface and/or a programmable data interface is described. In an operational mode, two or more CA interfaces may be active. In another operational mode, at least one, but not all, CA interfaces may be active. In an operational mode, all of the data interfaces may be active. In another operational mode, at least one, but not all, data interfaces may be active. The memory device can include circuitry to select: an operational mode; a sub-mode within an operational mode; one or more CA interfaces as the active CA interface(s); a main CA interface from multiple active CA interfaces; and/or one or more data interfaces as the active data interfaces. The circuitry may perform these selection(s) based on one or more bits in one or more registers and/or one or more signals received on one or more pins.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: August 15, 2017
    Assignee: RAMBUS INC.
    Inventors: Ian Shaeffer, Lawrence Lai, Fan Ho, David A. Secker, Wayne S. Richardson, Akash Bansal, Brian S. Leibowitz, Kyung Suk Oh
  • Patent number: 9721629
    Abstract: A system has a plurality of memory devices arranged in a fly-by topology, each having on-die termination (ODT) circuitry for connecting to an address and control (RQ) bus. The ODT circuitry of each memory device includes a set of one or more control registers for controlling on-die termination of one or more signal lines of the RQ bus. A first memory device includes a first set of one or more control registers storing a first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the first memory device, and a second memory device includes a second set of one or more control registers storing a second ODT value different from the first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the second memory device.
    Type: Grant
    Filed: December 29, 2016
    Date of Patent: August 1, 2017
    Assignee: RAMBUS INC.
    Inventors: Ian Shaeffer, Kyung Suk Oh
  • Publication number: 20170169878
    Abstract: A system has a plurality of memory devices arranged in a fly-by topology, each having on-die termination (ODT) circuitry for connecting to an address and control (RQ) bus. The ODT circuitry of each memory device includes a set of one or more control registers for controlling on-die termination of one or more signal lines of the RQ bus. A first memory device includes a first set of one or more control registers storing a first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the first memory device, and a second memory device includes a second set of one or more control registers storing a second ODT value different from the first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the second memory device.
    Type: Application
    Filed: December 29, 2016
    Publication date: June 15, 2017
    Inventors: Ian Shaeffer, Kyung Suk Oh
  • Patent number: 9660648
    Abstract: A memory control component outputs a memory write command to a memory IC and also outputs write data to be received via data inputs of the memory IC. Prior to reception of the write data within the memory IC, the memory control component asserts a termination control signal that causes the memory IC to apply to the data inputs a first on-die termination impedance during reception of the write data followed by a second on-die termination impedance after the write data has been received. The memory control component deasserts the termination control signal to cause the memory IC to apply no termination impedance to the data inputs.
    Type: Grant
    Filed: April 19, 2016
    Date of Patent: May 23, 2017
    Assignee: Rambus Inc.
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Publication number: 20170054576
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: September 8, 2016
    Publication date: February 23, 2017
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9570129
    Abstract: A system has a plurality of memory devices arranged in a fly-by topology, each having on-die termination (ODT) circuitry for connecting to an address and control (RQ) bus. The ODT circuitry of each memory device includes a set of one or more control registers for controlling on-die termination of one or more signal lines of the RQ bus. A first memory device includes a first set of one or more control registers storing a first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the first memory device, and a second memory device includes a second set of one or more control registers storing a second ODT value different from the first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the second memory device.
    Type: Grant
    Filed: March 25, 2016
    Date of Patent: February 14, 2017
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Kyung Suk Oh
  • Publication number: 20160351654
    Abstract: An on-die-capacitor structure includes a first capacitor and a second capacitor. The first capacitor may have first and second terminals. The first and second terminals are directly connected to first and second power supply rail structures, respectively. The first power supply rail structure is different from the second power supply rail structure. The second capacitor may have third and fourth terminals. The second capacitor is connected in series between the second power supply rail structure and a third power supply rail structure. The third power supply rail structure is different from the first and second power supply rail structures. The third and fourth terminals are directly connected to the second and third power supply rail structures, respectively. The first capacitor may have a first capacitance and the second capacitor structure may have a second capacitance that is greater than the first capacitance.
    Type: Application
    Filed: May 26, 2015
    Publication date: December 1, 2016
    Inventors: Kyung Suk Oh, Charu Sardana, Yanzhong Xu, Guang Chen
  • Publication number: 20160293236
    Abstract: A system has a plurality of memory devices arranged in a fly-by topology, each having on-die termination (ODT) circuitry for connecting to an address and control (RQ) bus. The ODT circuitry of each memory device includes a set of one or more control registers for controlling on-die termination of one or more signal lines of the RQ bus. A first memory device includes a first set of one or more control registers storing a first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the first memory device, and a second memory device includes a second set of one or more control registers storing a second ODT value different from the first ODT value, for controlling termination of one or more signal lines of the RQ bus by the ODT circuitry of the second memory device.
    Type: Application
    Filed: March 25, 2016
    Publication date: October 6, 2016
    Inventors: Ian Shaeffer, Kyung Suk Oh
  • Patent number: 9461631
    Abstract: A method of measuring duty-cycle distortion in a signal (e.g., flowing between an operating circuit and a memory circuit), where the signal has a known period, the signal being measured is in a first state during a first portion of the period, and is in a different state during a second portion of the period, includes advancing or retarding the signal until an edge of the signal intersects an edge of the other signal. From the amount of the advancing or retarding, the duty cycle and the magnitude of duty-cycle distortion are determined. This may be used to control correction of the duty-cycle distortion. An interpolator circuit may be used to advance or retard the signal. A processor may be used to keep track of the amount of advancing or retarding, to determine the duration of the duty cycle, and control correction of the duty-cycle distortion.
    Type: Grant
    Filed: February 5, 2015
    Date of Patent: October 4, 2016
    Assignee: Altera Corporation
    Inventors: Kyung Suk Oh, Sean Shau-Tu Lu
  • Patent number: 9455825
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: September 27, 2016
    Assignee: Rambus Inc.
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Publication number: 20160233863
    Abstract: A memory control component outputs a memory write command to a memory IC and also outputs write data to be received via data inputs of the memory IC. Prior to reception of the write data within the memory IC, the memory control component asserts a termination control signal that causes the memory IC to apply to the data inputs a first on-die termination impedance during reception of the write data followed by a second on-die termination impedance after the write data has been received. The memory control component deasserts the termination control signal to cause the memory IC to apply no termination impedance to the data inputs.
    Type: Application
    Filed: April 19, 2016
    Publication date: August 11, 2016
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Publication number: 20160209902
    Abstract: Disclosed embodiments relate to a system that changes transmitter and/or receiver settings to deal with reliability issues caused by a predetermined event, such as a change in a power state or a clock start event. One embodiment uses a first setting while operating a transmitter during a normal operating mode, and a second setting while operating the transmitter during a transient period following the predetermined event. A second embodiment uses similar first and second settings in a receiver, or in both a transmitter and a receiver employed on one side of a bidirectional link. The first and second settings can be associated with different swing voltages, edge rates, equalizations and/or impedances.
    Type: Application
    Filed: February 1, 2016
    Publication date: July 21, 2016
    Inventors: Yu Chang, Lei Luo, Kyung Suk Oh
  • Publication number: 20160142200
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: September 29, 2015
    Publication date: May 19, 2016
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9342095
    Abstract: Integrated circuit devices that operate in different modes. In a low data rate mode, data is transferred between the integrated circuit devices at a low data rate, or no data is transferred at all. In a high data rate mode, data is transferred between integrated circuit devices at a high data rate. A transition mode facilitates the transition from the low data rate mode to the high data rate mode. During the transition mode data is transferred between the integrated circuit devices at an intermediate data rate greater than the low data rate but lower than the high data rate. Also during the transition mode, parameters affecting the transmission of data between the integrated circuit devices are calibrated at the high data rate.
    Type: Grant
    Filed: February 24, 2012
    Date of Patent: May 17, 2016
    Assignee: Rambus Inc.
    Inventors: Kyung Suk Oh, Akash Bansal