Patents Assigned to Rambus Inc.
  • Patent number: 8745315
    Abstract: A memory system includes nonvolatile physical memory, such as flash memory, that exhibits a wear mechanism asymmetrically associated with write operations. A relatively small cache of volatile memory reduces the number of writes, and wear-leveling memory access methods distribute writes evenly over the nonvolatile memory.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: June 3, 2014
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, Ely K. Tsern
  • Patent number: 8743636
    Abstract: In memory module populated by memory components having a write-timing calibration mode, control information that specifies a write operation is received via an address/control signal path and write data corresponding to the write operation is received via a data signal path. Each memory component receives multiple delayed versions of a timing signal used to indicate that the write data is valid, and outputs signals corresponding to the multiple delayed versions of the timing signal to enable determination, in a memory controller, of a delay interval between outputting the control information on the address/control signal path and outputting the write data on the data signal path.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: June 3, 2014
    Assignee: Rambus Inc.
    Inventor: Frederick A. Ware
  • Patent number: 8743973
    Abstract: A receiver circuit to receive signals from first and second pairs of transmission lines includes first and second interfaces, each with first and second input nodes to receive respective signals. The receiver circuit also includes a resistor network with first, second, third, and fourth resistive elements. The first and second resistive elements are each connected between the input nodes of a respective interface. The third and fourth resistive elements each include a pair of resistors connected in series between the input nodes of a respective interface, and an intermediate node between the resistors. The intermediate nodes are connected to an AC ground. The receiver circuit further includes a differential amplifier with first and second inputs coupled respectively to the first and second interfaces and an output to provide a signal derived from common mode components of the signals received at the input nodes.
    Type: Grant
    Filed: May 25, 2011
    Date of Patent: June 3, 2014
    Assignee: Rambus Inc.
    Inventors: Lei Luo, Brian S. Leibowitz, Jared L. Zerbe, Barry W. Daly, Wayne D. Dettloff, John C. Eble, III, John Wilson
  • Publication number: 20140149654
    Abstract: A single-ended receiver includes an internal voltage generation circuit to set a first internal reference voltage (Vref). A model voltage generation circuit is configurable to receive an external reference voltage to be calibrated during an initial calibration. The model voltage generation circuit is configurable to track an offset value for voltage-temperature (VT) drift and the offset value is applied to the internal voltage generation circuit to calibrate the internal Vref during a periodic calibration of the single-ended receiver.
    Type: Application
    Filed: November 21, 2013
    Publication date: May 29, 2014
    Applicant: Rambus Inc.
    Inventors: Pravin Kumar Venkatesan, Kashinath Prabhu, Makarand Shirasgaonkar, Wayne Dettloff
  • Publication number: 20140149618
    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: November 14, 2013
    Publication date: May 29, 2014
    Applicant: Rambus Inc.
    Inventors: Pravin Kumar Venkatesan, Liji Gopalakrishnan, Kashinath Prabhu, Makarand Shirasgaonkar
  • Publication number: 20140145760
    Abstract: A transceiver includes a transmitter and receiver that form a series current path between two power-supply nodes. Powering both the transmitter and receiver with the same supply current saves power. The transmitter functions as a resistive load for the receiver, and thus performs useful work with power that would otherwise be dissipated as waste heat.
    Type: Application
    Filed: June 11, 2012
    Publication date: May 29, 2014
    Applicant: Rambus Inc.
    Inventors: Huy Nguyen, Kambiz Kaviani, Yohan Usthavvia Frans
  • Patent number: 8737162
    Abstract: In a low-power signaling system, an integrated circuit device includes an open loop-clock distribution circuit and a transmit circuit that cooperate to enable high-speed transmission of information-bearing symbols unaccompanied by source-synchronous timing references. The open-loop clock distribution circuit generates a transmit clock signal in response to an externally-supplied clock signal, and the transmit circuit outputs a sequence of symbols onto an external signal line in response to transitions of the transmit clock signal. Each of the symbols is valid at the output of the transmit circuit for a symbol time and a phase offset between the transmit clock signal and the externally-supplied clock signal is permitted to drift by at least the symbol time.
    Type: Grant
    Filed: July 9, 2009
    Date of Patent: May 27, 2014
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, Robert E. Palmer, John W. Poulton
  • Patent number: 8737106
    Abstract: A multi-die memory device includes a first die of a first type and configured to electrically interface with an external processor via a first synchronous interface operating at a first clock rate, and at least one second die of a second type and configured for data storage. Each second die transacts data with the first die via a second synchronous interface operating at a second clock rate, where the first clock rate is an integer multiple of the second clock rate, and where a timing reference associated with the second synchronous interface is transmitted by the first die to the second die.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: May 27, 2014
    Assignee: Rambus Inc.
    Inventors: Scott C. Best, Ming Li
  • Publication number: 20140139261
    Abstract: Described are integrated-circuit die with differential receivers, the inputs of which are coupled to external signal pads. Termination legs coupled to the signal pads support multiple termination topologies. These termination legs can support adjustable impedances, capacitances, or both, which may be controlled using an integrated memory.
    Type: Application
    Filed: May 30, 2013
    Publication date: May 22, 2014
    Applicant: Rambus Inc
    Inventor: Huy Nguyen
  • 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: 20140140389
    Abstract: An integrated circuit is disclosed that includes a receiver circuit to receive duobinary data symbols from a first signaling lane. The receiver circuit includes sampling circuitry to determine symbol state, and a duobinary decoder. The duobinary decoder is coupled to the sampling circuitry and converts the detected states to a PAM2 coded symbol stream. A decision-feedback equalizer (DFE) is provided that has inputs coupled to the sampling circuitry in parallel with the duobinary decoder. The DFE cooperates with the sampling circuitry to form a feedback path, such that the duobinary decoder is external to the feedback path.
    Type: Application
    Filed: November 6, 2013
    Publication date: May 22, 2014
    Applicant: Rambus Inc.
    Inventor: E-Hung Chen
  • Publication number: 20140140419
    Abstract: A single-ended data transmission system transmits a signal having a signal voltage that is referenced to a power supply voltage and that swings above and below the power supply voltage. The power supply voltage is coupled to a power supply rail that also serves as a signal return path. The signal voltage is derived from two signal supply voltages generated by a pair of charge pumps that draw substantially same amount of current from a power supply.
    Type: Application
    Filed: November 5, 2013
    Publication date: May 22, 2014
    Applicant: Rambus Inc.
    Inventors: John W. Poulton, Frederick A. Ware, Carl W. Werner
  • Publication number: 20140133536
    Abstract: A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2N?1 bits, where N is equal to or greater than 7, while the second calibration sequence utilizes short calibration patterns, such as fixed codes less than 16 bytes, and for example as short as 2 bytes long.
    Type: Application
    Filed: January 1, 2014
    Publication date: May 15, 2014
    Applicant: Rambus Inc.
    Inventors: Craig E. Hampel, Frederick A. Ware, Richard E. Perego
  • Patent number: 8716780
    Abstract: A memory device includes a planar substrate, a plurality of horizontal conductive planes above the planar substrate, and a plurality of horizontal insulating layers interleaved with the plurality of horizontal conductive planes. An array of vertical conductive columns, perpendicular to the pluralities of conductive planes and insulating layers, passes through apertures in the pluralities of conductive planes and insulating layers. The memory device includes a plurality of programmable memory elements, each of which couples one of the horizontal conductive planes to a respective vertical conductive column.
    Type: Grant
    Filed: August 26, 2010
    Date of Patent: May 6, 2014
    Assignee: Rambus Inc.
    Inventors: Mark D. Kellam, Gary B. Bronner
  • Patent number: 8717797
    Abstract: A dynamic random access memory (DRAM) device has a hierarchical bitline structure with local bitlines and global bitlines formed on different metal layers. The local bitlines are separated into a plurality of local bitline sections, and bitline isolation switches are configured to connect or disconnect the local bitline sections to or from the global bitlines. As a result, the local bitlines with higher per-length capacitance can be made shorter, since the global bitline with lower per-length capacitance is used to route the signal from the cell capacitances of the memory cells to the remote sense amplifiers.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: May 6, 2014
    Assignee: Rambus Inc.
    Inventor: Thomas Vogelsang
  • Patent number: 8717837
    Abstract: A memory module having memory components, a termination structure, an address/control signal path, a clock signal path, multiple data signal paths and multiple strobe signal paths. The strobe signal paths and data signal paths are coupled to respective memory components, and the address/control signal path and clock signal path are coupled in common to all the memory components. The address/control signal path extends along the memory components to the termination structure such that control signals propagating toward the termination structure arrive at address/control inputs of respective memory components at progressively later times corresponding to relative positions of the memory components.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: May 6, 2014
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, Ely K. Tsern, Richard E. Perego, Craig E. Hampel
  • Patent number: 8717052
    Abstract: Methods, systems, and apparatus for testing semiconductor devices. A semiconductor device includes one or more external terminals configured to receive fuse configuration data from an external source. The semiconductor device also includes a soft-blow circuit to generate a soft-blow signal based on the fuse configuration data, and a fuse circuit that includes a fuse and has first and second operational states corresponding to the fuse being intact and blown, respectively. The fuse circuit is configured to receive the soft-blow signal and to select its operational state to be the first or second operational state based on the received soft-blow signal.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: May 6, 2014
    Assignee: Rambus Inc.
    Inventors: Adrian E. Ong, Paul Fuller, Nick van Heel, Mark Thomann
  • Patent number: 8711922
    Abstract: A multi-phase partial response equalizer is disclosed. The equalizer includes receiver circuitry to receive a data symbol over N bit intervals and to generate N sets of samples in response to N clock signals having different phases. A first storage stage is provided, including storage elements to store the sets of samples during a common clock interval. First and second selection circuits are respectively coupled to an input and an output of the first storage stage. An output storage stage is coupled to the second selection circuit to store an output sample. The first and second selection circuits, over multiple clock intervals, cooperatively select the output sample from one of the sets of samples based on a most recent previous output sample.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: April 29, 2014
    Assignee: Rambus Inc.
    Inventors: Jie Shen, Ting Wu, Kun-Yang (Ken) Chang
  • Patent number: 8711996
    Abstract: An integrated circuit includes samplers, a phase error determination circuit, and periodic signal generators. The samplers generate respective sampled signals by sampling respective input signals in response to respective periodic signals. The input signals have a common phase error. The phase error determination circuit receives the sampled signals from the samplers. The phase error determination circuit generates a representation of the common phase error of the input signals in response to sampled signals received in a set-up mode in which the samplers sample respective input signals having a common bit pattern. The periodic signal generators generate the periodic signals differing in phase from one another by defined phase differences in the set-up mode and subject the periodic signals to a common phase shift in a normal mode in response to the representation of the common phase error. The common phase shift matches the common phase error of the input signals.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: April 29, 2014
    Assignee: Rambus Inc.
    Inventor: Kun-Yung Chang
  • Publication number: 20140112089
    Abstract: Methods and apparatuses for communicating information are described. In some embodiments, a first integrated circuit (IC) provides a clock signal and a data signal to a second IC, wherein the data bits of the data signal are timed according to the clock signal, and wherein the frequency of the clock signal is capable of being changed even when the data signal is valid.
    Type: Application
    Filed: October 9, 2013
    Publication date: April 24, 2014
    Applicant: Rambus Inc.
    Inventors: Brian Hing-Kit Tsang, Jared L. Zerbe