Patents by Inventor Liji Gopalakrishnan

Liji Gopalakrishnan 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: 20210011876
    Abstract: A memory device or module selects between alternative command ports. Memory systems with memory modules incorporating such memory devices support point-to-point connectivity and efficient interconnect usage for different numbers of modules. The memory devices and modules can be of programmable data widths. Devices on the same module can be configured select different command ports to facilitate memory threading. Modules can likewise be configured to select different command ports for the same purpose.
    Type: Application
    Filed: July 30, 2020
    Publication date: January 14, 2021
    Inventors: Liji Gopalakrishnan, Ian Shaeffer, Yi Lu
  • Publication number: 20200379926
    Abstract: A memory system includes a dynamic random access memory (DRAM) device, a second memory device, and a memory controller circuit. The memory controller circuit is coupled to the DRAM device by a first data channel configured to transfer first data between the memory controller circuit and the DRAM device on behalf of a host, and is also coupled to the DRAM device by a second data channel configured to transfer second data between the memory controller circuit and the DRAM device on behalf of the second memory device while the first data is being transferred across the first data bus.
    Type: Application
    Filed: May 13, 2020
    Publication date: December 3, 2020
    Inventor: Liji Gopalakrishnan
  • Publication number: 20200349997
    Abstract: An integrated circuit includes a physical layer interface having a control timing domain and a data timing domain, and circuits that enable the control timing domain during a change in power conservation mode in response to a first event, and that enable the data timing domain in response to a second event. The control timing domain can include interface circuits coupled to a command and address path, and the data timing domain can include interface circuits coupled to a data path.
    Type: Application
    Filed: May 4, 2020
    Publication date: November 5, 2020
    Inventors: Ian Shaeffer, Lei Luo, Liji Gopalakrishnan
  • Publication number: 20200335150
    Abstract: A dynamic random access memory (DRAM) component (e.g., module or integrated circuit) can be configured to have multiple rows in the same bank open concurrently. The controller of the component divides the address space of the banks into segments based on row address ranges. These row address ranges do not necessarily correspond to row address ranges of the bank's subarrays (a.k.a. memory array tiles—MATs). When a command is sent to open a row, the controller marks a plurality of the segments as blocked. The controller thereby tracks address ranges in a bank where it will not open a second row unless and until the first row is closed. The memory component may store information about which, and how many, segments should be blocked in response to opening a row. This information may be read by the controller during initialization.
    Type: Application
    Filed: April 2, 2020
    Publication date: October 22, 2020
    Inventors: Thomas VOGELSANG, John Eric LINSTADT, Liji GOPALAKRISHNAN
  • Publication number: 20200278902
    Abstract: A memory system employs an addressing scheme to logically divide rows of memory cells into separate contiguous regions, one for data storage and another for error detection and correction (EDC) codes corresponding to that data. Data and corresponding EDC codes are stored in the same row of the same bank. Accessing data and corresponding EDC code in the same row of the same bank advantageously saves power and avoids bank conflicts. The addressing scheme partitions the memory without requiring the requesting processor to have an understanding of the memory partition.
    Type: Application
    Filed: March 27, 2020
    Publication date: September 3, 2020
    Inventors: Frederick A. Ware, John E. Linstadt, Liji Gopalakrishnan
  • Patent number: 10747703
    Abstract: A memory device or module selects between alternative command ports. Memory systems with memory modules incorporating such memory devices support point-to-point connectivity and efficient interconnect usage for different numbers of modules. The memory devices and modules can be of programmable data widths. Devices on the same module can be configured select different command ports to facilitate memory threading. Modules can likewise be configured to select different command ports for the same purpose.
    Type: Grant
    Filed: July 23, 2019
    Date of Patent: August 18, 2020
    Assignee: Rambus Inc.
    Inventors: Liji Gopalakrishnan, Ian Shaeffer, Yi Lu
  • Publication number: 20200218675
    Abstract: A single-ended receiver is coupled to an input-output (I/O) pin of a command and address (CA) bus. The receiver is configurable with dual-mode I/O support to operate the CA bus in a low-swing mode and a high-swing mode. The receiver is configurable to receive a first command on the I/O pin while in the high-swing mode, initiate calibration of the slave device to operate in the low-swing mode in response to the first command, switch the slave device to operate in the low-swing mode while the CA bus remains active, and to receive a second command on the I/O pin while in the low-swing mode.
    Type: Application
    Filed: December 10, 2019
    Publication date: July 9, 2020
    Inventors: Pravin Kumar Venkatesan, Liji Gopalakrishnan, Kashinath Ullhas Prabhu, Makarand Ajit Shirasgaonkar
  • Patent number: 10665289
    Abstract: An integrated circuit includes a physical layer interface having a control timing domain and a data timing domain, and circuits that enable the control timing domain during a change in power conservation mode in response to a first event, and that enable the data timing domain in response to a second event. The control timing domain can include interface circuits coupled to a command and address path, and the data timing domain can include interface circuits coupled to a data path.
    Type: Grant
    Filed: July 11, 2018
    Date of Patent: May 26, 2020
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Lei Luo, Liji Gopalakrishnan
  • Patent number: 10613924
    Abstract: A memory system employs an addressing scheme to logically divide rows of memory cells into separate contiguous regions, one for data storage and another for error detection and correction (EDC) codes corresponding to that data. Data and corresponding EDC codes are stored in the same row of the same bank. Accessing data and corresponding EDC code in the same row of the same bank advantageously saves power and avoids bank conflicts. The addressing scheme partitions the memory without requiring the requesting processor to have an understanding of the memory partition.
    Type: Grant
    Filed: April 26, 2018
    Date of Patent: April 7, 2020
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, John Eric Linstadt, Liji Gopalakrishnan
  • Publication number: 20200065268
    Abstract: Memory controllers, devices, modules, systems and associated methods are disclosed. In one embodiment, an integrated circuit (IC) memory device is disclosed. The memory device includes an array of storage cells and command interface circuitry to receive an internal transfer command. In response to the internal transfer command, transfer logic reads data from a first portion of the array of storage cells, transfers the data as on-chip transfer data, and writes the on-chip transfer data to a second portion of the array of storage cells. In response to the command interface circuitry receiving an interrupt command, the transfer logic pauses the internal transfer operation, and carries out an unrelated memory access operation involving at least the first portion of the array of storage cells or the second portion of the array of storage cells.
    Type: Application
    Filed: August 20, 2019
    Publication date: February 27, 2020
    Inventors: Liji Gopalakrishnan, Frederick A. Ware, Brent S. Haukness
  • Publication number: 20200004714
    Abstract: A memory device or module selects between alternative command ports. Memory systems with memory modules incorporating such memory devices support point-to-point connectivity and efficient interconnect usage for different numbers of modules. The memory devices and modules can be of programmable data widths. Devices on the same module can be configured select different command ports to facilitate memory threading. Modules can likewise be configured to select different command ports for the same purpose.
    Type: Application
    Filed: July 23, 2019
    Publication date: January 2, 2020
    Inventors: Liji Gopalakrishnan, Ian Shaeffer, Yi Lu
  • Patent number: 10509741
    Abstract: A single-ended receiver is coupled to an input-output (I/O) pin of a command and address (CA) bus. The receiver is configurable with dual-mode I/O support to operate the CA bus in a low-swing mode and a high-swing mode. The receiver is configurable to receive a first command on the I/O pin while in the high-swing mode, initiate calibration of the slave device to operate in the low-swing mode in response to the first command, switch the slave device to operate in the low-swing mode while the CA bus remains active, and to receive a second command on the I/O pin while in the low-swing mode.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: December 17, 2019
    Assignee: Rambus Inc.
    Inventors: Pravin Kumar Venkatesan, Liji Gopalakrishnan, Kashinath Ullhas Prabhu, Makarand Ajit Shirasgaonkar
  • Patent number: 10380056
    Abstract: A memory device or module selects between alternative command ports. Memory systems with memory modules incorporating such memory devices support point-to-point connectivity and efficient interconnect usage for different numbers of modules. The memory devices and modules can be of programmable data widths. Devices on the same module can be configured select different command ports to facilitate memory threading. Modules can likewise be configured to select different command ports for the same purpose.
    Type: Grant
    Filed: July 12, 2017
    Date of Patent: August 13, 2019
    Assignee: Rambus Inc.
    Inventors: Liji Gopalakrishnan, Ian Shaeffer, Yi Lu
  • Publication number: 20190102327
    Abstract: A single-ended receiver is coupled to an input-output (I/O) pin of a command and address (CA) bus. The receiver is configurable with dual-mode I/O support to operate the CA bus in a low-swing mode and a high-swing mode. The receiver is configurable to receive a first command on the I/O pin while in the high-swing mode, initiate calibration of the slave device to operate in the low-swing mode in response to the first command, switch the slave device to operate in the low-swing mode while the CA bus remains active, and to receive a second command on the I/O pin while in the low-swing mode.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 4, 2019
    Inventors: Pravin Kumar Venkatesan, Liji Gopalakrishnan, Kashinath Ullhas Prabhu, Makarand Ajit Shirasgaonkar
  • Patent number: 10209922
    Abstract: A memory space of a module connected to a memory controller via a memory interface may be used as a command buffer. Commands received by the module via the command buffer are executed by the module. The memory controller may write to the command buffer out-of-order. The memory controller may delay or eliminate writes to the command buffer. Tags associated with commands are used to specify the order commands are executed. A status buffer in the memory space of the module is used to communicate whether commands have been received or executed. Information received via the status buffer can be used as a basis for a determination to re-send commands to the command buffer.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: February 19, 2019
    Assignee: Rambus Inc.
    Inventors: Liji Gopalakrishnan, Vlad Fruchter, Lawrence Lai, Pradeep Batra, Steven C. Woo, Wayne Frederick Ellis
  • Publication number: 20190043551
    Abstract: An integrated circuit includes a physical layer interface having a control timing domain and a data timing domain, and circuits that enable the control timing domain during a change in power conservation mode in response to a first event, and that enable the data timing domain in response to a second event. The control timing domain can include interface circuits coupled to a command and address path, and the data timing domain can include interface circuits coupled to a data path.
    Type: Application
    Filed: July 11, 2018
    Publication date: February 7, 2019
    Inventors: Ian Shaeffer, Lei Luo, Liji Gopalakrishnan
  • Publication number: 20180336089
    Abstract: A memory system employs an addressing scheme to logically divide rows of memory cells into separate contiguous regions, one for data storage and another for error detection and correction (EDC) codes corresponding to that data. Data and corresponding EDC codes are stored in the same row of the same bank. Accessing data and corresponding EDC code in the same row of the same bank advantageously saves power and avoids bank conflicts. The addressing scheme partitions the memory without requiring the requesting processor to have an understanding of the memory partition.
    Type: Application
    Filed: April 26, 2018
    Publication date: November 22, 2018
    Inventors: Frederick A. Ware, John Eric Linstadt, Liji Gopalakrishnan
  • Patent number: 10089256
    Abstract: A transmitter is coupled to a command and address (CA) bus. The transmitter is configurable with dual-mode support to send commands over the CA bus in a first swing mode and a second swing mode. The transmitter is configurable to send a first command over the CA bus via the pins while in the first swing mode, initiate calibration of the master device to send commands over the CA bus in the second swing mode, and to send a second command over the CA bus via the pins while in the second swing mode.
    Type: Grant
    Filed: June 7, 2017
    Date of Patent: October 2, 2018
    Assignee: Rambus Inc.
    Inventors: Pravin Kumar Venkatesan, Liji Gopalakrishnan, Kashinath Prabhu, Makarand Shirasgaonkar
  • Patent number: 10026466
    Abstract: An integrated circuit includes a physical layer interface having a control timing domain and a data timing domain, and circuits that enable the control timing domain during a change in power conservation mode in response to a first event, and that enable the data timing domain in response to a second event. The control timing domain can include interface circuits coupled to a command and address path, and the data timing domain can include interface circuits coupled to a data path.
    Type: Grant
    Filed: June 7, 2017
    Date of Patent: July 17, 2018
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Lei Luo, Liji Gopalakrishnan
  • Publication number: 20170372768
    Abstract: An integrated circuit includes a physical layer interface having a control timing domain and a data timing domain, and circuits that enable the control timing domain during a change in power conservation mode in response to a first event, and that enable the data timing domain in response to a second event. The control timing domain can include interface circuits coupled to a command and address path, and the data timing domain can include interface circuits coupled to a data path.
    Type: Application
    Filed: June 7, 2017
    Publication date: December 28, 2017
    Inventors: Ian Shaeffer, Lei Luo, Liji Gopalakrishnan