Patents by Inventor Ian P. Shaeffer

Ian P. 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: 20140164823
    Abstract: Components of a memory system, such as a memory controller and memory device, which detect accumulated memory read disturbances and correct such disturbances before they reach a level that causes errors. The memory device includes a memory array and a disturbance control circuit. The memory array includes a plurality of memory rows. Each memory row is associated with a disturbance warning circuit having a state that corresponds to an accumulated disturbance in the memory row. The disturbance control circuit determines, responsive to an activation of a memory row of the plurality of memory rows specified by a row access command, whether the disturbance condition is present in the memory row based on the state of the disturbance warning circuit associated with the memory row. If a disturbance condition is present, the disturbance control circuit causes a recovery operation to be performed on the memory row to reduce the accumulated disturbances.
    Type: Application
    Filed: December 5, 2013
    Publication date: June 12, 2014
    Applicant: Rambus Inc.
    Inventors: Hongzhong Zheng, Brent Haukness, Mehmet Günhan Ertosun, Ian P. Shaeffer
  • Patent number: 8749042
    Abstract: Multiple devices, including a first device and a second device, have operational circuitry and opposing first and second surfaces. First and second electrical contacts are formed at the first surface, while a third electrical contact is formed at the second surface opposite the first electrical contact. The first electrical contact is electrically connected to the operational circuitry, and the second electrical contact is electrically connected to the third electrical contact. The first device and the second device are subsequently stacked such that the first surface of the second device is located adjacent the second surface of the first device such that the first electrical contact of the second device is aligned with the third electrical contact of the first device. The first electrical contact of the second device is electrically connected to the third electrical contact of the first device.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: June 10, 2014
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, Ely K. Tsern, Ian P. Shaeffer
  • Publication number: 20140140149
    Abstract: A memory controller includes an interface to receive a data strobe signal and corresponding read data. The data strobe signal and the read data correspond to a read command issued by the memory controller, and the read data is received in accordance with the data strobe signal and an enable signal. A circuit in the memory controller is to dynamically adjust a timing offset between the enable signal and the data strobe signal, and control logic is to issue a supplemental read command in accordance with a determination that a time interval since a last read command issued by the memory controller exceeds a predetermined value.
    Type: Application
    Filed: August 5, 2013
    Publication date: May 22, 2014
    Applicant: Rambus Inc.
    Inventors: Bret Stott, Frederick A. Ware, Ian P. Shaeffer, Yuanlong Wang
  • Publication number: 20140108889
    Abstract: A memory system supporting error detection and correction (EDC) coverage. The system includes a memory controller and a memory buffer. The memory buffer includes an interface to a first group of memory devices and an interface to a second group of memory devices. The memory buffer accesses data from the first group of memory devices and accesses first error information corresponding to the data from the second group of devices. The memory buffer also accesses additional data from the second group of memory devices and accesses second error information corresponding to the additional data from a device in the first group of memory devices. EDC coverage may also be configured by the memory controller so that some data accesses have EDC coverage and other data accesses do not have EDC coverage.
    Type: Application
    Filed: May 14, 2012
    Publication date: April 17, 2014
    Applicant: RAMBUS INC.
    Inventor: Ian P. Shaeffer
  • Patent number: 8638637
    Abstract: A memory controller having a time-staggered request signal output. A first timing signal is generated while a second timing signal is generated having a first phase difference relative to the first timing signal. An address value is transmitted in response to the first timing signal and a control value is transmitted in response to the second timing signal, the address value and control value constituting portions of a first memory access request.
    Type: Grant
    Filed: December 19, 2012
    Date of Patent: January 28, 2014
    Assignee: Rambus Inc.
    Inventors: Ian P. Shaeffer, Bret Stott, Benedict C. Lau
  • Publication number: 20140016423
    Abstract: Components of a memory system, such as a memory controller and a memory device, that reduce delay in exiting self-refresh mode by controlling the refresh timing of the memory device. The memory device includes a memory core. An interface circuit of the memory device receives an external refresh signal indicating an intermittent refresh event. A refresh circuit of the memory device generates an internal refresh signal indicating an internal refresh event of the memory device. A refresh control circuit of the memory device performs a refresh operation on a portion of the memory core responsive to the internal refresh event, at a time relative to the intermittent refresh event indicated by the external refresh signal.
    Type: Application
    Filed: July 9, 2013
    Publication date: January 16, 2014
    Inventors: Frederick A. Ware, Brent Haukness, Ian P. Shaeffer, James E. Harris
  • Patent number: 8610455
    Abstract: In an integrated circuit device having dynamically selected on-die termination, a set of data inputs are coupled respectively to a set of termination circuits, each termination circuit having multiple controllable termination impedance configurations.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: December 17, 2013
    Assignee: Rambus Inc.
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Patent number: 8610459
    Abstract: An integrated circuit device transmits, to a dynamic random access memory device (DRAM), a write command indicating that write data is to be sampled by a data interface of the DRAM, and a plurality of commands that specify programming a plurality of control values into a plurality of corresponding registers in the DRAM. The plurality of control values include first and second control values that indicate respective first and second terminations that the DRAM is to apply to the data interface during a time interval that begins a predetermined amount of time after the DRAM receives the write command, the first termination to be applied during a first portion of the time interval while the data interface is sampling the write data and the second termination to be applied during a second portion of the time interval after the write data is sampled.
    Type: Grant
    Filed: May 24, 2012
    Date of Patent: December 17, 2013
    Assignee: Rambus Inc.
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Patent number: 8599631
    Abstract: A system includes a plurality of memory devices arranged in a fly-by topology, each of the memory devices having on-die termination (ODT) circuitry for connection to an address and control (RQ) bus. The ODT circuitry has at least one input for controlling termination of one or more signal lines of the RQ bus. Application of a first logic level to the at least one input enables termination of the one or more signal lines. Application of a second logic level to the at least one input disables termination of the one or more signal lines.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: December 3, 2013
    Assignee: Rambus Inc.
    Inventors: Ian P. Shaeffer, Kyung S. Oh
  • Publication number: 20130307584
    Abstract: An integrated circuit memory device stores a plurality of digital values that specify respective termination impedances. The memory device switchably couples respective sets of load elements to a data input/output (I/O) to apply the termination impedances specified by the digital values, including, applying a first termination impedance to the data I/O during an idle state of the memory device, applying a first one of two non-equal termination impedances to the data I/O while the memory device receives write data in a memory write operation and applying a second one of the two non-equal termination impedances to the data I/O while another memory device receives write data in a memory write operation. When outputting read data via the data I/O in a memory read operation, the memory device switchably couples to the data I/O at least a portion of the load elements included in the sets of load elements.
    Type: Application
    Filed: July 26, 2013
    Publication date: November 21, 2013
    Applicant: Rambus Inc.
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Publication number: 20130254585
    Abstract: A memory controller includes a clock generator to generate a first clock signal and a timing circuit to generate a second clock signal from the first clock signal. The second clock signal times communications with any of a plurality of memory devices in respective ranks, including a first memory device in a first rank and a second memory device in a second rank. The timing circuit is configured to adjust a phase of the first clock signal, when the memory controller is communicating with the second memory device, based on calibration data associated with the second memory device and timing adjustment data associated with feedback from at least the first memory device.
    Type: Application
    Filed: November 9, 2011
    Publication date: September 26, 2013
    Applicant: RAMBUS INC.
    Inventors: Jared L. Zerbe, Ian P. Shaeffer, John Eble
  • Publication number: 20130201770
    Abstract: Row activation operations within a memory component are carried out with respect to subrows instead of complete storage rows to reduce power consumption. Further, instead of activating subrows in response to row commands, subrow activation operations are deferred until receipt of column commands that specify the column operation to be performed and the subrow to be activated.
    Type: Application
    Filed: June 8, 2012
    Publication date: August 8, 2013
    Inventors: James Edward Harris, Thomas Vogelsang, Frederick A. Ware, Ian P. Shaeffer
  • Patent number: 8504788
    Abstract: A memory controller includes an interface to receive a data strobe signal and corresponding read data. The data strobe signal and the read data correspond to a read command issued by the memory controller, and the read data is received in accordance with the data strobe signal and an enable signal. A circuit in the memory controller is to dynamically adjust a timing offset between the enable signal and the data strobe signal, and control logic is to issue a supplemental read command if a time interval since a last read command issued by the memory controller exceeds a predetermined value.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: August 6, 2013
    Assignee: Rambus Inc.
    Inventors: Bret Stott, Frederick A. Ware, Ian P. Shaeffer, Yuanlong Wang
  • Publication number: 20130148447
    Abstract: Components of a memory system, such as a memory controller or memory device, that operate in different power states to reduce the overall power consumption of the memory system. In some of the power states, distribution circuitry that distributes a timing signal within the components may be powered on when the output of the distribution circuitry is needed. In other power states, the distribution circuitry may be powered off when the output of the distribution circuitry is not needed. Additionally, power states in the memory device may be triggered off memory access commands issued by the memory controller.
    Type: Application
    Filed: December 6, 2012
    Publication date: June 13, 2013
    Inventors: Ian P. Shaeffer, Jared L. Zerbe, Frederick A. Ware
  • Patent number: 8380943
    Abstract: A memory module having a plurality of memory devices and a memory buffer that translates between a variable width primary data port and a plurality of fixed width secondary data ports, each of which is coupled to one of the memory devices. The translation is effected by distributing the width of the primary data port to all or to a subset of the secondary data ports. In another aspect, the invention comprises a memory buffer that supports adjustable data width in a variety of ways.
    Type: Grant
    Filed: January 7, 2009
    Date of Patent: February 19, 2013
    Assignee: Rambus Inc.
    Inventor: Ian P. Shaeffer
  • Patent number: 8344475
    Abstract: In a system having a memory device, an event is detected during system operation. The memory device is heated to reverse use-incurred degradation of the memory device in response to detecting the event. In another system, the memory device is heated to reverse use-incurred degradation concurrently with execution of a data access operation within another memory device of the system. In another system having a memory controller coupled to first and second memory devices, data is evacuated from the first memory device to the second memory device in response to determining that a maintenance operation is needed within the first memory device.
    Type: Grant
    Filed: August 19, 2010
    Date of Patent: January 1, 2013
    Assignee: Rambus Inc.
    Inventors: Ian P. Shaeffer, Gary B. Bronner, Brent S. Haukness, Kevin S. Donnelly, Frederick A. Ware, Mark A. Horowitz
  • Patent number: 8339878
    Abstract: A memory controller having a time-staggered request signal output. A first timing signal is generated while a second timing signal is generated having a first phase difference relative to the first timing signal. An address value is transmitted in response to the first timing signal and a control value is transmitted in response to the second timing signal, the address value and control value constituting portions of a first memory access request.
    Type: Grant
    Filed: December 23, 2011
    Date of Patent: December 25, 2012
    Assignee: Rambus Inc.
    Inventors: Ian P. Shaeffer, Bret Stott, Benedict C. Lau
  • Publication number: 20120265930
    Abstract: An integrated circuit device transmits, to a dynamic random access memory device (DRAM), a write command indicating that write data is to be sampled by a data interface of the DRAM, and a plurality of commands that specify programming a plurality of control values into a plurality of corresponding registers in the DRAM. The plurality of control values include first and second control values that indicate respective first and second terminations that the DRAM is to apply to the data interface during a time interval that begins a predetermined amount of time after the DRAM receives the write command, the first termination to be applied during a first portion of the time interval while the data interface is sampling the write data and the second termination to be applied during a second portion of the time interval after the write data is sampled.
    Type: Application
    Filed: May 24, 2012
    Publication date: October 18, 2012
    Inventors: Kyung Suk Oh, Ian P. Shaeffer
  • Publication number: 20120188835
    Abstract: A memory controller having a time-staggered request signal output. A first timing signal is generated while a second timing signal is generated having a first phase difference relative to the first timing signal. An address value is transmitted in response to the first timing signal and a control value is transmitted in response to the second timing signal, the address value and control value constituting portions of a first memory access request.
    Type: Application
    Filed: December 23, 2011
    Publication date: July 26, 2012
    Inventors: Ian P. Shaeffer, Bret Stott, Benedict C. Lau
  • Patent number: 8188762
    Abstract: A control component outputs to an integrated circuit device an indication to apply one of a plurality of controllable termination impedance configurations at a data input of the integrated circuit device. The indication causes the integrated circuit device to apply a first of the controllable termination impedance configurations at the data input during a first internal state of the integrated circuit device corresponding to the reception of write data on the data input, and causes the integrated circuit device to apply a second of the controllable termination impedance configurations at the data input during a second internal state of the integrated circuit device that follows the first internal state.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: May 29, 2012
    Assignee: Rambus Inc.
    Inventors: Kyung Suk Oh, Ian P. Shaeffer