Abstract: During system initialization, each data buffer device and/or memory device on a memory module is configured with a unique (at least to the module) device identification number. In order to access a single device (rather than multiple buffers and/or memory devices), a target identification number is written to all of the devices using a command bus connected to all of the data buffer devices or memory devices, respectively. The devices whose respective device identification numbers do not match the target identification number are configured to ignore future command bus transactions (at least until the debug mode is turned off.) The selected device that is configured with a device identification number matching the target identification number is configured to respond to command bus transactions.

Abstract: Memory controllers, devices, modules, systems and associated methods are disclosed. In one embodiment, an integrated circuit (IC) memory controller is disclosed. The IC memory controller includes a first controller command/address (C/A) interface to transmit first and second read commands for first and second read data to a first memory C/A interface of a first bank group of memory. A second command/address (C/A) interface transmits third and fourth read commands for third and fourth read data to a second memory C/A interface of a second bank group of memory. Receiver circuitry receives the first and second read data via a first data link interface and the third and fourth read data via the second data link interface. For a first operating mode, the first and second read data are received after respective first delays following transmission of the first and second read commands and at a first serialization ratio.

Abstract: A memory system includes dynamic random-access memory (DRAM) components that include interconnected and redundant component data interfaces. The redundant interfaces facilitate memory interconnect topologies that accommodate considerably more DRAM components per memory channel than do traditional memory systems, and thus offer considerably more memory capacity per channel, without concomitant reductions in signaling speeds. Each DRAM component includes multiplexers that allow either of the data interfaces to write data to or read data from a common set of memory banks, and to selectively relay write and read data to and from other components, bypassing the local banks. Delay elements can impose selected read/write delays to align read and write transactions from and to disparate DRAM components.

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.

Abstract: An integrated circuit comprises a signal transmitter and a sampling circuit coupled to the signal transmitter, wherein the sampling circuit is to sample output voltage levels of an output of the signal transmitter at different respective times. The integrated circuit further comprises a measurement circuit coupled to the sampling circuit, wherein the measurement circuit is to compare the output voltage levels of the output of the signal transmitter to corresponding reference voltages to identify a first time when a first output voltage level equals a first reference voltage and a second time when a second output voltage level equals a second reference voltage. A time difference between the first time and the second time is used to configure a slew rate adjustment control of the signal transmitter.

Abstract: A first sequence of data bits is shifted into storage elements of a signal receiver during a first sequence of bit-time intervals, and a memory access command indicates that a second sequence of data bits is to be received within the signal receiver during a second sequence of bit-time intervals. Contents of the shift-register storage elements are conditionally overwritten with a predetermined set of seed bits, depending on whether one or more bit-time intervals will transpire between the first and second sequences of bit-time intervals. Equalization signals generated based, at least in part, on contents of the shift-register storage elements are used to adjust respective signal levels representative of one or more bits of the second sequence of data bits.

Abstract: A memory module includes at least two memory devices. Each of the memory devices perform verify operations after attempted writes to their respective memory cores. When a write is unsuccessful, each memory device stores information about the unsuccessful write in an internal write retry buffer. The write operations may have only been unsuccessful for one memory device and not any other memory devices on the memory module. When the memory module is instructed, both memory devices on the memory module can retry the unsuccessful memory write operations concurrently. Both devices can retry these write operations concurrently even though the unsuccessful memory write operations were to different addresses.

Abstract: A multi-rank memory system in which calibration operations are performed between a memory controller and one rank of memory while data is transferred between the controller and other ranks of memory. A memory controller performs a calibration operation that calibrates parameters pertaining to transmission of data via a first data bus between the memory controller and a memory device in a first rank of memory. While the controller performs the calibration operation, the controller also transfers data with a memory device in a second rank of memory via a second data bus.

Abstract: A memory module comprises an address buffer circuit, a command/address channel, and a plurality of memory components controlled by the address buffer circuit via the command/address channel. At least one memory component comprises a plurality of data ports, a memory core to store data, and a data interface. The data interface is capable of transferring data between the memory core and the data ports. The data interface supports a first data width mode in which the data interface transfers data at a first bit width and a first burst length via the data ports. The data interface also supports a second data width mode in which the data interface transfers data at a second bit width and second burst length via the data ports. The first bit width is greater than the second bit width and the first burst length is shorter than the second burst length.

Abstract: In one embodiment, a memory device includes a memory core and input receivers to receive commands and data. The memory device also includes a register to store a value that indicates whether a subset of the input receivers are powered down in response to a control signal. A memory controller transmits commands and data to the memory device. The memory controller also transmits the value to indicate whether a subset of the input receivers of the memory device are powered down in response to the control signal. In addition, in response to a self-fresh command, the memory device defers entry into a self-refresh operation until receipt of the control signal that is received after receiving the self-refresh command.

Abstract: A multi-element device includes a plurality of memory elements, each of which includes a memory array, access circuitry to control access to the memory array, and power control circuitry. The power control circuitry, which includes one or more control registers for storing first and second control values, controls distribution of power to the access circuitry in accordance with the first control value, and controls distribution of power to the memory array in accordance with the second control value. Each memory element also includes sideband circuitry for enabling a host system to set at least the first control value and the second control value in the one or more control registers.

Abstract: A combinational logic circuit includes input circuitry to receive a first and second input signals that transition between supply voltages of first and second voltage domain, respectively. The input circuitry generates, based on the first and second input signals, a first internal signal that transitions between one of the supply voltages of the first voltage domain and one of the supply voltages of the second voltage domain. Output circuitry within the combinational logic circuit generates an output signal that transitions between the upper and lower supply voltages of the first voltage domain in response to transition of the first internal signal.

Abstract: A system includes a memory controller and a memory device having a command interface, refresh circuitry, control logic, and a plurality of memory banks, each with a plurality of rows of memory cells. The command interface is operable to receive a refresh command from a memory controller and the refresh circuitry is configured to perform one or more refresh operations to refresh data stored in at least one bank of the plurality of memory banks during a refresh time interval in response to the refresh command from the memory controller. The control logic is to configure the command interface to enter a calibration mode during the refresh time interval, and the command interface is configured to perform a calibration operation in the calibration mode during the refresh time interval.

Abstract: A memory module can be programmed to deliver relatively wide, low-latency data in a first access mode, or to sacrifice some latency in return for a narrower data width, a narrower command width, or both, in a second access mode. The narrow, higher-latency mode requires fewer connections and traces. A controller can therefore support more modules, and thus increased system capacity. Programmable modules thus allow computer manufacturers to strike a desired balance between memory latency, capacity, and cost.

Abstract: A memory device comprising a programmable command-and-address (CA) interface and/or a programmable data interface is described. In an operational mode, two or more CA interfaces may be active. In another operational mode, at least one, but not all, CA interfaces may be active. In an operational mode, all of the data interfaces may be active. In another operational mode, at least one, but not all, data interfaces may be active. The memory device can include circuitry to select: an operational mode; a sub-mode within an operational mode; one or more CA interfaces as the active CA interface(s); a main CA interface from multiple active CA interfaces; and/or one or more data interfaces as the active data interfaces. The circuitry may perform these selection(s) based on one or more bits in one or more registers and/or one or more signals received on one or more pins.

Abstract: An integrated circuit (IC) memory device includes an array of storage cells configured into multiple banks. Interface circuitry receives refresh commands from a host memory controller to refresh the multiple banks for a first refresh mode. On-die refresh control circuitry selectively generates local refresh commands to refresh the multiple banks in cooperation with the host memory controller during a designated hidden refresh interval in a second refresh mode. Mode register circuitry stores a value indicating whether the on-die refresh control circuitry is enabled for use during the second refresh mode. The interface circuitry includes backchannel control circuitry to transmit a corrective action control signal during operation in the second refresh mode.

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.

Abstract: A memory device is disclosed that includes a row of storage locations that form plural columns. The plural columns include data columns to store data and a tag column to store tag information associated with error locations in the data columns. Each data column is associated with an error correction location including an error code bit location. Logic retrieves and stores the tag information associated with the row in response to activation of the row. A bit error in an accessed data column is repaired by a spare bit location based on the tag information.

Abstract: A memory system includes a dynamic random access memory (DRAM) device, a second memory device, and a memory controller circuit. The memory controller circuit is coupled to the DRAM device by a first data channel configured to transfer first data between the memory controller circuit and the DRAM device on behalf of a host, and is also coupled to the DRAM device by a second data channel configured to transfer second data between the memory controller circuit and the DRAM device on behalf of the second memory device while the first data is being transferred across the first data bus.

Abstract: A cache memory includes cache lines to store information. The stored information is associated with physical addresses that include first, second, and third distinct portions. The cache lines are indexed by the second portions of respective physical addresses associated with the stored information. The cache memory also includes one or more tables, each of which includes respective table entries that are indexed by the first portions of the respective physical addresses. The respective table entries in each of the one or more tables are to store indications of the second portions of respective physical addresses associated with the stored information.