Rambus Inc.

Cryptography Research, Inc.

Cadence Design Systems, Inc.

Yeung, Chi-ming

Woo, Steven

Perego, Richard

Batra, Pradeep

Lai, Lawrence

Steven Cameron Woo

Craig Edward Hampel

Ian P Shaeffer

Thomas J Giovannini

Alok Gupta

Thomas Vogelsang

Ely K Tsern

Richard Maurice Barth

Michael Raymond Miller

Pradeep Batra

Michael T Ching

David A Secker

Thomas J Sheffler

Frederick Abbott Ware

Lawrence Lai

Vlad Fruchter

Ramprasad Satagopan

Richard E Perego

Billy Wayne Garrett, Jr

Taeksang Song

Ravindranath T Kollipara

Catherine Yuhjung Chen

Abhijit Mukund Abhyankar

John Eric Linstadt

Bohuslav Rychlik

Christopher Haywood

Keith Lowery

Liji Gopalakrishnan

Benjamin Che-Ming Jun

Evan Lawrence Erickson

Torsten Partsch

Chi-Ming Yeung

Ronald Lee

Matthew Evan Orzen

Joel Patrick Wittenauer

George Michael Uhler

Chi-Ming (Philip) Yeung

Mark A Horowitz

Scott C Best

Donald C Stark

Wayne Frederick Ellis

Wayne S Richardson

Jun Y Kim

Qi Lin

Chad A Bellows

Liang Leon Peng

Kurt T Knorpp

Sreeja Menon

Kartik Dayalal Kariya

Don Stark

John Philip Privitera

Amit Kedia

Brent Steven Haukness

Dongyun Lee

Trung Am Diep

Mark D Kellam

Bradley A May

Liewei Bao

Amogh Agrawal

Joseph James Tringali

Brian H Tsang

Pooneh Safayenikoo

Michael Ching

A buffer integrated circuit (IC) chip is disclosed. The buffer IC chip includes host interface circuitry to receive a read command to retrieve read data from a memory. Memory interface circuitry couples to the memory. Data freshness authentication circuitry performs a freshness verification operation on the read data. Read data forwarding circuitry, in a skid mode of operation, transmits the read data to the host prior to completion of the freshness verification operation.

Buffer device with low-latency skid mode for data freshness

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.

Memory device having hidden refresh

A high-capacity cache memory is implemented by multiple heterogenous DRAM dies, including a dedicated tag-storage DRAM die architected for low-latency tag-address retrieval and thus rapid hit/miss determination, and one or more capacity-optimized cache-line DRAM dies that render a net cache-line storage capacity orders of magnitude beyond that of state-of-the art SRAM cache implementations. The tag-storage die serves double-duty in some implementations, yielding rapid tag hit/miss determination for cache-line read/write requests while also serving as a high-capacity snoop-filter in a memory-sharing multiprocessor environment.

DRAM cache with stacked, heterogenous tag and data dies

An apparatus and method for flexible metadata allocation and caching. In one embodiment of the method first and second requests are received from first and second applications, respectively, wherein the requests specify a reading of first and second data, respectively, from one or more memory devices. The circuit reads the first and second data in response to receiving the first and second requests. Receiving first and second metadata from the one or more memory devices in response to receiving the first and second requests. The first and second metadata correspond to the first and second data, respectively. The first and second data are equal in size, and the first and second metadata are unequal in size.

Flexible metadata allocation and caching

A memory system includes two or more memory controllers capable of accessing the same dynamic, random-access memory (DRAM), one controller having access to the DRAM or a subset of the DRAM at a time. Different subsets of the DRAM are supported with different refresh-control circuitry, including respective refresh-address counters. Whichever controller has access to a given subset of the DRAM issues refresh requests to the corresponding refresh-address counter. Counters are synchronized before control of a given subset of the DRAM is transferred between controllers to avoid a loss of stored data.

Multi-modal refresh of dynamic, random-access memory

A DRAM includes at least four groups of memory cores and at least four memory access channel interfaces that, in a first mode, each respectively are to receive memory access commands, directed to a corresponding one of the groups of memory cores. One-half of the memory access channel interfaces are to, in a second mode, each respectively receive memory access commands, directed to a corresponding two of four of the groups of memory cores. The memory access channel interfaces to have electrical connection conductors that lie on opposing sides of at least one line of reflectional symmetry from a second one-half of the one-half of the at least four memory access channel interfaces.

Quad-channel DRAM

An application-specific integrated circuit for an artificial neural network is integrated with a high-bandwidth memory. A processing die with tiled neural-network processing units is bonded to a stack of memory dies with memory banks laid out to establish relatively short connections to overlying processing units. The memory banks form vertical groups of banks for each overlying processing unit. A switch matrix on the processing die allows each processing unit to communicate with its vertical group of banks via a short, fast inter-die memory channel or with more remote groups of banks under neighboring processing units.

Methods and circuits for aggregating processing units and dynamically allocating memory

An interconnected stack of one or more Dynamic Random Access Memory (DRAM) die has a base logic die and one or more custom logic or processor die. The processor logic die snoops commands sent to and through the stack. In particular, the processor logic die may snoop mode setting commands (e.g., mode register set—MRS commands). At least one mode setting command that is ignored by the DRAM in the stack is used to communicate a command to the processor logic die. In response the processor logic die may prevent commands, addresses, and data from reaching the DRAM die(s). This enables the processor logic die to send commands/addresses and communicate data with the DRAM die(s). While being able to send commands/addresses and communicate data with the DRAM die(s), the processor logic die may execute software using the DRAM die(s) for program and/or data storage and retrieval.

Stacked device communication

Command/address and timing information is distributed to buffer integrated circuits on a module using multiple wavelengths of light modulated with the same information. Each individual wavelength of modulated light carrying command/address information is received by a corresponding single buffer device that deserializes the command/address information and communicates it electrically to memory devices(s). Likewise, each individual wavelength of modulated light carrying timing/synchronization/clock information is received by a corresponding single buffer device and used to synchronize accesses to the memory device(s). Thus, multiple buffer integrated circuits on a module each receive information from the CPU using different wavelengths of light transmitted on the same waveguide.

Bus distribution using multiwavelength multiplexing

The creation, maintenance, and accessing of page tables is done by a virtual machine monitor running on a computing system rather than the guest operating systems. This allows page table walks to be completed in fewer memory accesses when compared to the guest operating system's maintenance of the page tables. In addition, the virtual machine monitor may utilize additional resources to offload page table access and maintenance functions from the CPU to another device, such as a page table management device or page table management node. Offloading some or all page table access and maintenance functions to a specialized device or node enables the CPU to perform other tasks during page table walks and/or other page table maintenance functions.

Page table manager

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.

Method and apparatus for calibrating write timing in a memory system

A memory system includes a memory controller, a plurality of serial data buffers, and a plurality of memory devices. The memory controller issues packetized commands and data to the serial data buffers. The serial data buffers each apply a different remapping function to remap an input command address in the packetized commands to respective remapped memory addresses that are different for each serial data buffer. The serial data buffers then issue commands to the memory devices using the remapped addresses. The remapping functions may be designed to mitigate row hammer effects. The serial data buffers may furthermore apply transformations to read and write data to facilitate encryption and decryption.

Data buffer for memory devices with memory address remapping

Multiple device stacks are interconnected in a ring topology. The inter-device stack communication may utilize a handshake protocol. This ring topology may include the host so that the host may initialize and load the device stacks with data and/or commands (e.g., software, algorithms, etc.). The inter-device stack interconnections may also be configured to include/remove the host and/or to implement varying numbers of separate ring topologies. By configuring the system with more than one ring topology, and assigning different problems to different rings, multiple, possibly unrelated, machine learning tasks may be performed in parallel by the device stack system.

Stacked device system

System and method for improved transferring of data involving memory device systems. A memory appliance (MA) comprising a plurality of memory modules is configured to store data within the plurality of memory modules and further configured to receive data commands from the first server and a second server coupled to the MA. The data commands may include direction memory access commands such that the MA can service the data commands while bypassing a host controller of the MA.

Memory appliance couplings and operations

An interconnected stack of one or more Dynamic Random Access Memory (DRAM) die also has one or more custom logic, controller, or processor die. The custom die(s) of the stack include direct channel interfaces that allow direct access to memory regions on one or more DRAMs in the stack. The direct channels are time-division multiplexed such that each DRAM die is associated with a time slot on a direct channel. The custom die configures a first DRAM die to read a block of data and transmit it via the direct channel using a time slot that is assigned to a second DRAM die. The custom die also configures the second memory device to receive the first block of data in its assigned time slot and write the block of data.

Block copy

Growing community of inventors

Saratoga, CA, United States of America

Steven Cameron Woo