Patents by Inventor Ian Shaeffer

Ian Shaeffer 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: 20140347950
    Abstract: Described are memory modules that support dynamic point-to-point extensibility using fixed-width memory die. The memory modules include data-width translators that allow the modules to vary the effective width of their external memory interfaces without varying the width of the internal memory interfaces extending between the translators and associated fixed-width dies. The data-width translators use a data-mask signal to selectively prevent memory accesses to subsets of physical addresses. This data masking divides the physical address locations into two or more temporal subsets of the physical address locations, effectively increasing the number of uniquely addressable locations in a given module. Reading temporal addresses in write order can introduce undesirable read latency. Some embodiments reorder read data to reduce this latency.
    Type: Application
    Filed: March 3, 2014
    Publication date: November 27, 2014
    Inventor: Ian Shaeffer
  • Patent number: 8868873
    Abstract: In a reconfigurable data strobe-based memory system, data strobes may be re-tasked in different modes of operation. For example, in one mode of operation a differential data strobe may be used as a timing reference for a given set of data signals. In a second mode of operation, one of the components of the differential data strobe may be used as a timing reference for a first portion of the set of data signals and the other component used as a timing reference for a second portion of the set of data signals. Different data mask-related schemes also may be invoked for different modes of operation. For example, in a first mode of operation a memory controller may generate a data mask signal to prevent a portion of a set of data from being written to a memory array. Then, in a second mode of operation the memory controller may invoke a coded value replacement scheme or a data strobe transition inhibition scheme to prevent a portion of a set of data from being written to a memory array.
    Type: Grant
    Filed: August 25, 2008
    Date of Patent: October 21, 2014
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Frederick Ware, Craig E. Hampel
  • Patent number: 8842492
    Abstract: Multiple timing reference signals (e.g., clock signals) each cycling at the same frequency are distributed in a fly-by topology to a plurality of memory devices in various embodiments are presented. These multiple clock signals each have a different phase relationship to each other (e.g., quadrature). A first circuit receives a first of these clocks as a first timing reference signal. A second circuit receives a second of these clocks as a second timing reference signal. A plurality of receiver circuits receive signals synchronously with respect to the first timing reference signal and the second timing reference signal, such that a first signal value is resolved using the first timing reference signal and a second signal value is resolved using the second timing reference signal.
    Type: Grant
    Filed: November 19, 2011
    Date of Patent: September 23, 2014
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Frederick A. Ware, Scott C. Best
  • Publication number: 20140237152
    Abstract: A memory module comprises a data interface including a plurality of data lines and a plurality of configurable switches coupled between the data interface and a data path to one or more memories. The effective width of the memory module can be configured by enabling or disabling different subsets of the configurable switches. The configurable switches may be controlled by manual switches, by a buffer on the memory module, by an external memory controller, or by the memories on the memory module.
    Type: Application
    Filed: February 18, 2014
    Publication date: August 21, 2014
    Applicant: Rambus Inc.
    Inventors: AMIR AMIRKHANY, SURESH RAJAN, RAVINDRANATH KOLLIPARA, IAN SHAEFFER, DAVID A. SECKER
  • Publication number: 20140223068
    Abstract: Systems, among other embodiments, include topologies (data and/or control/address information) between an integrated circuit buffer device (that may be coupled to a master, such as a memory controller) and a plurality of integrated circuit memory devices. For example, data may be provided between the plurality of integrated circuit memory devices and the integrated circuit buffer device using separate segmented (or point-to-point link) signal paths in response to control/address information provided from the integrated circuit buffer device to the plurality of integrated circuit buffer devices using a single fly-by (or bus) signal path. An integrated circuit buffer device enables configurable effective memory organization of the plurality of integrated circuit memory devices. The memory organization represented by the integrated circuit buffer device to a memory controller may be different than the actual memory organization behind or coupled to the integrated circuit buffer device.
    Type: Application
    Filed: August 30, 2013
    Publication date: August 7, 2014
    Applicant: Rambus Inc.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel
  • Publication number: 20140189466
    Abstract: Systems and methods are provided for detecting and correcting address errors in a memory system. In the memory system, a memory device generates an error-detection code based on an address transmitted via an address bus and transmits the error-detection code to a memory controller. The memory controller transmits an error indication to the memory device in response to the error-detection code.
    Type: Application
    Filed: March 7, 2014
    Publication date: July 3, 2014
    Applicant: Rambus Inc.
    Inventors: Ian Shaeffer, Craig E. Hampel
  • Publication number: 20140112084
    Abstract: A memory controller is disclosed. The memory controller is configured to be connected to one or more memory devices via an address and control (RQ) bus. Each of the memory devices have on-die termination (ODT) circuitry connected to a subset of signal lines of the RQ bus, and the memory controller is operable to selectively disable the ODT circuitry in at least one memory device of the one or more memory devices.
    Type: Application
    Filed: November 22, 2013
    Publication date: April 24, 2014
    Applicant: Rambus Inc.
    Inventors: Ian Shaeffer, Kyung Suk Oh
  • Patent number: 8707110
    Abstract: Systems and methods are provided for detecting and correcting address errors in a memory system. In the memory system, a memory device generates an error-detection code based on an address transmitted via an address bus and transmits the error-detection code to a memory controller. The memory controller transmits an error indication to the memory device in response to the error-detection code. The error indication causes the memory device to remove the received address and prevent a memory operation.
    Type: Grant
    Filed: September 6, 2013
    Date of Patent: April 22, 2014
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Craig E. Hampel
  • Patent number: 8707009
    Abstract: Described are memory modules that support dynamic point-to-point extensibility using fixed-width memory die. The memory modules include data-width translators that allow the modules to vary the effective width of their external memory interfaces without varying the width of the internal memory interfaces extending between the translators and associated fixed-width dies. The data-width translators use a data-mask signal to selectively prevent memory accesses to subsets of physical addresses. This data masking divides the physical address locations into two or more temporal subsets of the physical address locations, effectively increasing the number of uniquely addressable locations in a given module. Reading temporal addresses in write order can introduce undesirable read latency. Some embodiments reorder read data to reduce this latency.
    Type: Grant
    Filed: September 26, 2012
    Date of Patent: April 22, 2014
    Assignee: Rambus Inc.
    Inventor: Ian Shaeffer
  • Publication number: 20140068169
    Abstract: A memory module includes a substrate having signal lines thereon that form a control path and a plurality of data paths. A plurality of memory devices are mounted on the substrate. Each memory device is coupled to the control path and to a distinct data path. The memory module includes control circuitry to enable each memory device to process a distinct respective memory access command in a succession of memory access commands and to output data on the distinct data path in response to the processed memory access command.
    Type: Application
    Filed: June 20, 2013
    Publication date: March 6, 2014
    Inventors: Frederick Ware, Craig E. Hampel, Ian Shaeffer, Scott C. Best
  • Publication number: 20140052934
    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 26, 2013
    Publication date: February 20, 2014
    Applicant: Rambus Inc.
    Inventors: Liji Gopalakrishnan, Ian Shaeffer, Yi Lu
  • Patent number: 8645617
    Abstract: This disclosure provides a non-volatile memory device that concurrently processes multiple page reads, erases or writes involving the same memory space. The device relies upon a crossbar and a set of page buffers that may each be dynamically assigned to each read or write request. The device also separates memory array control from IO control, such that multiple cycle state change operations can be performed while the buffers are used to transfer data into and out of the buffers along an external data bus; using this structure, the memory device can accept multiple transactions where pages can be immediately loaded into buffers and then “pipelined” either for transfer to a write data register or to an external bus as appropriate. By significantly mitigating the substantial “busy time” associated with program and erase of non-volatile memory devices, especially flash devices, this disclosure greatly expands potential application of such devices.
    Type: Grant
    Filed: October 15, 2009
    Date of Patent: February 4, 2014
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Brent Steven Haukness
  • Publication number: 20140006691
    Abstract: This disclosure provides a method of accurately determining expected transaction times associated with flash memory subdivisions, such as devices, blocks or pages. By performing a test transaction to program each bit of each such unit, the maximum expected programming time of each unit may be determined in advance and used for scheduling purposes. For example, in a straightforward implementation, a relatively accurate, empirically measured time limit may be identified and used to efficiently manage and schedule flash memory transactions without awaiting ultimate resolution of attempts to write to a non-responsive page. This disclosure also provides other uses of empirically-measured maximum flash memory transaction times, including via multiple memory modes and prioritized memory; for example, if a high performance mode is desired, low variation in flash memory transaction times may be tolerated, and units not satisfying these principles may be marked relatively quickly.
    Type: Application
    Filed: June 13, 2013
    Publication date: January 2, 2014
    Inventors: Brent Haukness, Ian Shaeffer
  • Publication number: 20140002131
    Abstract: Local on-die termination controllers for effecting termination of a high-speed signaling links simultaneously engage on-die termination structures within multiple integrated-circuit memory devices disposed on the same memory module, and/or within the same integrated-circuit package, and coupled to the high-speed signaling link. A termination control bus is coupled to memory devices on a module, and provides for peer-to-peer communication of termination control signals.
    Type: Application
    Filed: January 20, 2012
    Publication date: January 2, 2014
    Applicant: RAMBUS INC.
    Inventor: Ian Shaeffer
  • Publication number: 20130346721
    Abstract: A first timing reference signal and a second timing reference signal are sent to a memory device. The second timing reference signal has approximately a quadrature phase relationship with respect to the first timing reference signal. A plurality of serial data patterns are received from the memory device. The transitions of the first timing reference and the second timing reference determining when transitions occur between the bits of the plurality of data patterns. Timing indicators associated with when received transitions occur between the bits of the plurality of data patterns are received from the memory device. The timing indicators are each measured using a single sampler. Based on the timing indicators, a first duty cycle adjustment for the first timing reference signal, a second duty cycle adjustment for the second timing reference signal, and a quadrature phase adjustment are determined and applied.
    Type: Application
    Filed: March 21, 2012
    Publication date: December 26, 2013
    Applicant: Rambus Inc.
    Inventors: Thomas Giovannini, Scott Best, Lei Luo, Ian Shaeffer
  • Publication number: 20130339775
    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: March 8, 2012
    Publication date: December 19, 2013
    Applicant: RAMBUS INC.
    Inventors: Ian Shaeffer, Lei Luo, Liji Gopalakrishnan
  • Publication number: 20130314968
    Abstract: The disclosed embodiments relate to the design of a memory system which includes a set of one or more memory modules, wherein each memory module in the set has a clamshell configuration, wherein pairs of opposing memory packages containing memory chips are located on opposite sides of the memory module. The memory system also includes a multi-drop path containing signal lines which pass through the set of memory modules, and are coupled to memory packages in the set of memory modules. For a given signal line in the multi-drop path, a first memory package and a second memory package that comprise a given pair of opposing memory packages are coupled to the given signal line at a first location and a second location, respectively, wherein the first location and the second location are separated from each other by a distance d1 along the given signal line.
    Type: Application
    Filed: February 7, 2012
    Publication date: November 28, 2013
    Inventors: Ian Shaeffer, Ravindranath Kollipara
  • Patent number: 8555116
    Abstract: Systems and methods are provided for detecting and correcting address errors in a memory system. In the memory system, a memory device generates an error-detection code based on an address transmitted via an address bus and transmits the error-detection code to a memory controller. The memory controller transmits an error indication to the memory device in response to the error-detection code. The error indication causes the memory device to remove the received address and prevent a memory operation.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: October 8, 2013
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Craig E. Hampel
  • Publication number: 20130258755
    Abstract: An embodiment is directed to an integrated circuit device having programmable input capacitance. For example, a programmable register of a memory device may store a value representative of an adjustment to the input capacitance value of a control pin. An embodiment is directed to controlling the skew of a synchronous memory system by allowing programmability of the lighter loaded pins in order to increase their load to match the more heavily loaded pins. By matching lighter loaded pins to more heavily loaded pins, the system exhibits improved synchronization of propagation delays of the control and address pins. In addition, an embodiment provides the ability to vary the loading depending on how many ranks are on the device.
    Type: Application
    Filed: March 18, 2013
    Publication date: October 3, 2013
    Applicant: RAMBUS, INC.
    Inventors: Ravindranath Kollipara, Lei Luo, Ian Shaeffer
  • Patent number: 8539152
    Abstract: Systems, among other embodiments, include topologies (data and/or control/address information) between an integrated circuit buffer device (that may be coupled to a master, such as a memory controller) and a plurality of integrated circuit memory devices. For example, data may be provided between the plurality of integrated circuit memory devices and the integrated circuit buffer device using separate segmented (or point-to-point link) signal paths in response to control/address information provided from the integrated circuit buffer device to the plurality of integrated circuit buffer devices using a single fly-by (or bus) signal path. An integrated circuit buffer device enables configurable effective memory organization of the plurality of integrated circuit memory devices. The memory organization represented by the integrated circuit buffer device to a memory controller may be different than the actual memory organization behind or coupled to the integrated circuit buffer device.
    Type: Grant
    Filed: May 31, 2011
    Date of Patent: September 17, 2013
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel