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).

  • Patent number: 8068357
    Abstract: A memory controller operates in two modes to support different types of memory devices. In a first mode, the memory controller distributes a dedicated reference voltage with each of a plurality of signal bundles to a corresponding plurality of memory devices. The reference voltages are conveyed using pads that are alternatively used for e.g. timing-reference signals in a second mode, so the provision for bundle-specific reference voltages need not increase the number of pads on the memory controller.
    Type: Grant
    Filed: September 4, 2008
    Date of Patent: November 29, 2011
    Assignee: Rambus Inc.
    Inventors: Frederick Ware, John Wilson, John C. Eble, III, Jade M. Kizer, Lei Luo, John W. Poulton, Ian Shaeffer
  • Publication number: 20110228614
    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: May 31, 2011
    Publication date: September 22, 2011
    Applicant: RAMBUS INC.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel
  • Publication number: 20110216611
    Abstract: A system that calibrates timing relationships between signals involved in performing write operations is described. This system includes a memory controller which is coupled to a set of memory chips, wherein each memory chip includes a phase detector configured to calibrate a phase relationship between a data-strobe signal and a clock signal received at the memory chip from the memory controller during a write operation. Furthermore, the memory controller is configured to perform one or more write-read-validate operations to calibrate a clock-cycle relationship between the data-strobe signal and the clock signal, wherein the write-read-validate operations involve varying a delay on the data-strobe signal relative to the clock signal by a multiple of a clock period.
    Type: Application
    Filed: May 19, 2011
    Publication date: September 8, 2011
    Applicant: RAMBUS INC.
    Inventors: Thomas J. Giovannini, Alok Gupta, Ian Shaeffer, Steven C. Woo
  • Publication number: 20110208905
    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: Application
    Filed: October 15, 2009
    Publication date: August 25, 2011
    Applicant: RAMBUS INC.
    Inventors: Ian Shaeffer, Brent Steven Haukness
  • Publication number: 20110191526
    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: December 23, 2008
    Publication date: August 4, 2011
    Inventors: Brent Haukness, Ian Shaeffer
  • Publication number: 20110066792
    Abstract: This disclosure provides a method and system that segment flash memory to have differently managed regions. More particularly, flash memory is segmented into a “non-volatile” region, where program counts are restricted to preserve baseline retention assumptions, and a “volatile” region, where program counts are unrestricted. Contrary to conventional wisdom, wear leveling is not performed on all flash memory, as the volatile region is regarded as degraded, and as the non-volatile region has program counts restricted to promote long-term retention. More than two regions may also be created; each of these may be associated with intermediate program counts and volatility expectations, and wear leveling may be applied to each of these on an independent basis if desired. Refresh procedures may optionally be applied to the region of flash memory which is treated as volatile memory.
    Type: Application
    Filed: February 4, 2009
    Publication date: March 17, 2011
    Applicant: RAMBUS INC.
    Inventors: Ian Shaeffer, Brent Haukness
  • Publication number: 20110060875
    Abstract: A memory system (100B) includes an array of non-volatile memory cells (140) and a memory controller (110) having a first port (port connected to line 101) to receive a program command that addresses a number of the memory cells for a programming operation, having a second port (port connected to lines 102 and 103) coupled to the memory array via a command pipeline, and configured to create a plurality of fractional program commands in response to the program command. Execution of each fractional program command applies a single program pulse to the addressed memory cells to incrementally program the addressed memory cells with program data, where the duration of the program pulse associated with each fractional program command is a selected fraction of the total programming time typically required to program the memory cells.
    Type: Application
    Filed: May 6, 2009
    Publication date: March 10, 2011
    Inventors: Brent S. Haukness, Ian Shaeffer, Gary B. Bronner
  • Publication number: 20110016278
    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: March 5, 2009
    Publication date: January 20, 2011
    Inventors: Frederick Ware, Craig E. Hampel, Ian Shaeffer, Scott C. Best
  • Publication number: 20110004726
    Abstract: Embodiments of a circuit are described. This circuit includes control logic that generates multiple piecewise-erase commands to erase information stored in a storage cell of a memory device formed within another circuit. Note that execution of a single one of the multiple piecewise-erase commands within the memory device may be insufficient to erase the information stored in the storage cell. Moreover, the first circuit includes an interface that receives the multiple piecewise-erase commands from the control logic and that transmits the multiple piecewise-erase commands to the memory device.
    Type: Application
    Filed: February 19, 2009
    Publication date: January 6, 2011
    Applicant: RAMBUS INC.
    Inventors: Brent S. Haukness, Ian Shaeffer, Gary B. Bronner
  • Patent number: 7836378
    Abstract: An integrated circuit, such as an integrated circuit memory or buffer device, method and system, among other embodiments, generate a plurality of error codes, such as CRC codes, corresponding to control information, write data and read data transactions, respectively. The plurality of separately generated CRC codes is logged or stored in respective storage circuits, such as circular buffers. The stored plurality of CRC codes corresponding to each transaction then may be used to determine whether an error occurred during a particular transaction and thus whether a retry of the particular transaction is issued. The integrated circuit includes a compare circuit to compare a CRC code generated by the integrated circuit with a CRC code provided by a controller device. A CRC code corresponding to read data is transferred to a controller device using a data mask signal line that is not being used during a read transaction.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: November 16, 2010
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Craig Hampel, Yuanlong Wang, Fred Ware
  • Publication number: 20100268901
    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: Application
    Filed: August 25, 2008
    Publication date: October 21, 2010
    Inventor: Ian Shaeffer
  • Publication number: 20100180143
    Abstract: Techniques for improved timing control of memory devices are disclosed. In one embodiment, the techniques may be realized as a memory controller to communicate with a memory device via a communications link. The memory controller may comprise a memory interface to exchange data with the memory device via a set of N conductors according to at least one clock, the data being encoded such that each M bits of data are represented by at least one symbol and each symbol is associated with a combination of signal levels on a group of n conductors, wherein M<N and n is equal to at least one and at most N. The memory may also comprise clock control logic to receive timing calibration information from the memory device and to output a signal to adjust a phase of the at least one clock based on the timing calibration information.
    Type: Application
    Filed: April 14, 2008
    Publication date: July 15, 2010
    Applicant: Rambus Inc.
    Inventors: Frederick A. Ware, Carl Werner, Ian Shaeffer
  • Publication number: 20100146199
    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: February 10, 2010
    Publication date: June 10, 2010
    Applicant: RAMBUS INC.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel
  • Patent number: 7729151
    Abstract: A system includes a master device and a first memory module having a plurality of integrated circuit memory devices and a plurality of integrated circuit buffer devices that operate in first and second modes of operation (bypass mode). In a first mode of operation, a first memory module provides read data from the plurality of integrated circuit memory devices (via a integrated circuit buffer device) on a first signal path to the master and a second memory module simultaneously provides read data from its plurality of integrated circuit memory devices (via another integrated circuit buffer device on the second module) on a third signal path coupled to the master device.
    Type: Grant
    Filed: July 28, 2006
    Date of Patent: June 1, 2010
    Assignee: Rambus Inc.
    Inventors: Ely Tsern, Ian Shaeffer, Craig Hampel
  • Patent number: 7685364
    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: April 15, 2009
    Date of Patent: March 23, 2010
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel
  • Publication number: 20100050010
    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: October 27, 2009
    Publication date: February 25, 2010
    Applicant: Rambus Inc.
    Inventor: Ian Shaeffer
  • Patent number: 7610417
    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: November 30, 2005
    Date of Patent: October 27, 2009
    Assignee: Rambus Inc.
    Inventor: Ian Shaeffer
  • Publication number: 20090235113
    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: April 15, 2009
    Publication date: September 17, 2009
    Applicant: RAMBUS INC.
    Inventors: Ian Shaeffer, Craig E. Hampel
  • Publication number: 20090198924
    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: April 15, 2009
    Publication date: August 6, 2009
    Applicant: Rambus Inc.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel
  • Patent number: 7562271
    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: April 6, 2007
    Date of Patent: July 14, 2009
    Assignee: Rambus Inc.
    Inventors: Ian Shaeffer, Ely Tsern, Craig Hampel