Patents Assigned to Rambus
  • Patent number: 11682448
    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: Grant
    Filed: June 28, 2022
    Date of Patent: June 20, 2023
    Assignee: Rambus Inc.
    Inventors: Thomas J. Giovannini, Alok Gupta, Ian Shaeffer, Steven C. Woo
  • Patent number: 11681648
    Abstract: The timing of the synchronous interface is controlled by a clock signal driven by a controller. The clock is toggled in order to send a command to a memory device via the interface. If there are no additional commands to be sent via the interface, the controller suspends the clock signal. When the memory device is ready, the memory device drives a signal back to the controller. The timing of this signal is not dependent upon the clock signal. Receipt of this signal by the controller indicates that the memory device is ready and the clock signal should be resumed so that a status of the command can be returned via the interface, or another command issued via the interface.
    Type: Grant
    Filed: December 22, 2021
    Date of Patent: June 20, 2023
    Assignee: Rambus Inc.
    Inventor: Yuanlong Wang
  • Patent number: 11683050
    Abstract: Memory controllers, devices and associated methods are disclosed. In one embodiment, a memory controller includes write circuitry to transmit write data to a memory device, the write circuitry includes a write error detection correction (EDC) encoder to generate first error information associated with the write data. Data bus inversion (DBI) circuitry conditionally inverts data bits associated with each of the write data words based on threshold criteria. Read circuitry receives read data from the memory device. The read circuitry includes a read EDC encoder to generate second error information associated with the received read data. Logic evaluates the first and second error information and conditionally reverse-inverts at least a portion of the read data based on the decoding.
    Type: Grant
    Filed: May 13, 2022
    Date of Patent: June 20, 2023
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, John Eric Linstadt
  • Patent number: 11681342
    Abstract: A circuit interface includes one or more processors that generate opcodes, a plurality of interface control circuits, each including a respective processing element responsive to the opcodes generated by one or more processors. Each interface control circuit corresponds to a respective link of a plurality of links of a device-to-device interface (DDI), and each link of the plurality of links of the DDI is for transmitting or receiving signals from one or more sources or one or more destinations external to the circuit.
    Type: Grant
    Filed: January 4, 2021
    Date of Patent: June 20, 2023
    Assignee: RAMBUS INC.
    Inventor: Stephen G. Tell
  • Patent number: 11683057
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Grant
    Filed: November 16, 2021
    Date of Patent: June 20, 2023
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Nhat Nguyen, Yikui Jen Dong, Arash Zargaran-Yazd, Wendemagegnehu Beyene
  • Patent number: 11681632
    Abstract: A memory controller includes logic circuitry to generate a first data address identifying a location in a first external memory array for storing first data, a first tag address identifying a location in a second external memory array for storing a first tag, a second data address identifying a location in the second external memory array for storing second data, and a second tag address identifying a location in the first external memory array for storing a second tag. The memory controller includes an interface that transfers the first data address and the first tag address for a first set of memory operations in the first and the second external memory arrays. The interface transfers the second data address and the second tag address for a second set of memory operations in the first and the second external memory arrays.
    Type: Grant
    Filed: October 6, 2020
    Date of Patent: June 20, 2023
    Assignee: Rambus Inc.
    Inventor: Frederick A. Ware
  • Patent number: 11675657
    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 15, 2022
    Date of Patent: June 13, 2023
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, John E. Linstadt, Liji Gopalakrishnan
  • Patent number: 11677571
    Abstract: A physically unclonable function circuit (PUF) is used to generate a fingerprint value based on the uniqueness of the physical characteristics (e.g., resistance, capacitance, connectivity, etc.) of a tamper prevention (i.e., shielding) structure that includes through-silicon vias and metallization on the backside of the integrated circuit. The physical characteristics depend on random physical factors introduced during manufacturing. This causes the chip-to-chip variations in these physical characteristics to be unpredictable and uncontrollable which makes more difficult to duplicate, clone, or modify the structure without changing the fingerprint value. By including the through-silicon vias and metallization on the backside of the integrated circuit as part of the PUF, the backside of the chip can be protected from modifications that can be used to help learn the secure cryptographic keys and/or circumvent the secure cryptographic (or other) circuitry.
    Type: Grant
    Filed: November 30, 2017
    Date of Patent: June 13, 2023
    Assignee: Rambus Inc.
    Inventor: Scott C. Best
  • Patent number: 11677487
    Abstract: In a general aspect, a network transmission interface can include, within an egress data path, a physical coding sublayer (PCS) operating in a constant bitrate domain for transmitting data frames on a network link; a timestamp unit configured to insert timestamps in payloads of the frames; a transmission media access control (MAC) unit located at a boundary between the constant bitrate domain and a variable bitrate domain, configured to receive the frames at a variable bitrate, encapsulate the frames, and provide the encapsulated frames at a constant bitrate; a MAC layer security unit located downstream from the timestamp unit, configured to sign and optionally encrypt the payloads and expand each frame with a security tag and an integrity check value (ICV). The timestamp unit and the MAC layer security unit (26b) can both operate in the constant bitrate domain.
    Type: Grant
    Filed: June 28, 2021
    Date of Patent: June 13, 2023
    Assignee: Rambus Inc.
    Inventor: Maksym Demchenko
  • Patent number: 11677391
    Abstract: A latency controller within an integrated circuit device retimes command-stream-triggered control and timing signals into endpoint timing domains having respective time-varying phase offsets relative to a reference clock by iteratively estimating and logging the phase offsets independently of commands streaming into the integrated circuit device.
    Type: Grant
    Filed: January 26, 2022
    Date of Patent: June 13, 2023
    Assignee: Rambus Inc.
    Inventors: Robert E. Palmer, Andrew M. Fuller, William F. Stonecypher
  • Patent number: 11671522
    Abstract: Embodiments of the present invention are directed to memories used in server applications. More specifically, embodiments of the present invention provide a server that has memory management module that is connected to the processor using one or more DDR channels. The memory management module is configured to provide the processor local access and network access to memories on a network. There are other embodiments as well.
    Type: Grant
    Filed: August 27, 2021
    Date of Patent: June 6, 2023
    Assignee: Rambus Inc.
    Inventor: Christopher Haywood
  • Patent number: 11671108
    Abstract: Disclosed is a successive approximation register (SAR) analog to digital converter (ADC) that uses two or more comparators. This allows the output of one comparator to be latched while the other comparators are comparing and switching. Statistical measures are used to correct the offsets of one or more of the comparators. If a statistically significant mismatch in the number of 1's and 0's occurs in a subset of the bits, adjustments to the offsets of one or more of the comparators are made until there is roughly an equal number of 1 and 0 values. This can reduce or eliminate the need for dedicated offset correction cycles.
    Type: Grant
    Filed: April 25, 2022
    Date of Patent: June 6, 2023
    Assignee: Rambus Inc.
    Inventors: Kenneth C. Dyer, Marcus Van Ierssel
  • Patent number: 11669379
    Abstract: A controller includes a link interface that is to couple to a first link to communicate bi-directional data and a second link to transmit unidirectional error-detection information. An encoder is to dynamically add first error-detection information to at least a portion of write data. A transmitter, coupled to the link interface, is to transmit the write data. A delay element is coupled to an output from the encoder. A receiver, coupled to the link interface, is to receive second error-detection information corresponding to at least the portion of the write data. Error-detection logic is coupled to an output from the delay element and an output from the receiver. The error-detection logic is to determine errors in at least the portion of the write data by comparing the first error-detection information and the second error-detection information, and, if an error is detected, is to assert an error condition.
    Type: Grant
    Filed: April 25, 2022
    Date of Patent: June 6, 2023
    Assignee: Rambus Inc.
    Inventors: Yuanlong Wang, Frederick A. Ware
  • Patent number: 11671286
    Abstract: A receiver utilizes loop-unrolled decision feedback equalization (DFE). For each sample, two comparators, each configured with different thresholds, sample an input signal. The output of one of these comparators is selected and used as the output of the receiver and may be optionally input to additional DFE circuitry. The output of the other (non-selected) comparator is used to adjust an input offset voltage of that same comparator. Adjustments to the offset voltages of the comparators may be based on a statistical analysis of the respective outputs of the two comparators when not selected. Adjustments to the offset voltages of the comparators may be based on comparisons between the respective outputs of the two comparators when not selected to the outputs of a reference comparator that has been calibrated for minimal or zero offset.
    Type: Grant
    Filed: December 10, 2019
    Date of Patent: June 6, 2023
    Assignee: Rambus Inc.
    Inventors: Mohammad Sadegh Jalali, Marcus Van Ierssel
  • Patent number: 11669124
    Abstract: A memory controller having a data receiver to sample data at a sample timing using a strobe signal, wherein the data and the strobe signal are sent by a memory device in connection with a read operation initiated by the memory controller, and a strobe receiver to receive the strobe signal, wherein a phase of the strobe signal has a drift relative to a reference by an amount. The memory controller further having a monitoring circuit to monitor the strobe signal and determine the amount of the drift, and an adjustment circuit to update the sample timing of the data receiver based on the amount of drift determined by the monitoring signal.
    Type: Grant
    Filed: April 7, 2022
    Date of Patent: June 6, 2023
    Assignee: Rambus Inc.
    Inventors: Scott C. Best, Abhijit M. Abhyankar, Kun-Yung Chang, Frank Lambrecht
  • Patent number: 11664332
    Abstract: A camouflaged application specific integrated circuit is disclosed. The camouflaged ASIC includes at least one camouflaged FinFET, which includes a substrate of a first conductivity type, a fin, disposed on the substrate, the fin including a source region of a second conductivity type, a drain region of the second conductivity type, and a channel region of the first conductivity type. The camouflaged application specific integrated circuit also includes a gate disposed over and substantially perpendicular to the channel region, forming one or more transistor junctions with the fin. In one embodiment, the substrate includes a punch through stop (PTS) region of the second conductivity type disposed between the fin and the substrate, the PTS region electrically shorting the source region of the fin to the drain region of the fin.
    Type: Grant
    Filed: January 25, 2021
    Date of Patent: May 30, 2023
    Assignee: RAMBUS INC.
    Inventors: Lap Wai Chow, Bryan J. Wang, James P. Baukus, Ronald P. Cocchi
  • Patent number: 11663138
    Abstract: Memory pages are background-relocated from a low-latency local operating memory of a server computer to a higher-latency memory installation that enables high-resolution access monitoring and thus access-demand differentiation among the relocated memory pages. Higher access-demand memory pages are background-restored to the low-latency operating memory, while lower access-demand pages are maintained in the higher latency memory installation and yet-lower access-demand pages are optionally moved to yet higher-latency memory installation.
    Type: Grant
    Filed: December 6, 2021
    Date of Patent: May 30, 2023
    Assignee: Rambus Inc.
    Inventors: Evan Lawrence Erickson, Christopher Haywood, Mark D. Kellam
  • Patent number: 11665028
    Abstract: An integrated circuit equalizes a data signal expressed as a series of symbols. The symbols form data patterns with different frequency components. By considering these patterns, the integrated circuit can experiment with equalization settings specific to a subset of the frequency components, thereby finding an equalization control setting that optimizes equalization. Optimization can be accomplished by setting the equalizer to maximize symbol amplitude.
    Type: Grant
    Filed: September 23, 2021
    Date of Patent: May 30, 2023
    Assignee: Rambus Inc.
    Inventor: Ramin Farjad-Rad
  • Patent number: 11664907
    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: Grant
    Filed: January 13, 2022
    Date of Patent: May 30, 2023
    Assignee: Rambus Inc.
    Inventors: Craig E. Hampel, Frederick A. Ware, Richard E. Perego
  • Patent number: 11664067
    Abstract: An integrated circuit device outputs a sequence of differently delayed calibration data timing signals to a DRAM component via a data-signal timing line as part of a timing calibration operation and then stores a delay value, based on at least one of the calibration data timing signals, that compensates for a difference in signal propagation times over the data-signal timing line and a command/address-signal timing line. After the timing calibration operation, the integrated circuit device outputs write data to the DRAM component and outputs a write data timing signal, delayed according to the delay value, to via the data-signal timing line to time reception of the first write data within the DRAM.
    Type: Grant
    Filed: August 2, 2021
    Date of Patent: May 30, 2023
    Assignee: Rambus Inc.
    Inventor: Frederick A. Ware