Rambus Inc.

Sony Electronics Inc

Other

Kurt T Knorpp

Jun Y Kim

Donald C Stark

Wayne S Richardson

Natsuki Kushiyama

Michael Tak-Kei Ching

Lee-Lean Shu

Katsunori Seno

Chad A Bellows

Steven Cameron Woo

Michael T Ching

Frederick Abbott Ware

Lawrence Lai

Kishore Ven Kasamsetty

Wayne Fang

Embodiments of a memory device are described. This memory device includes a signal connector which is electrically coupled to a command/address (CA) link, and an interface circuit, which is electrically coupled to the signal connector, and which receives CA packets via the CA link. A given CA packet includes an address field having address information corresponding to one or more storage locations in the memory device. Moreover, the memory device includes control logic having two operating modes, where, during a first operating mode, the control logic decodes address information in the CA packets using full-field sampling, and, during the second operating mode, the control logic decodes a portion of the address information in the CA packets using sub-field sampling.

Request-command encoding for reduced-data-rate testing

An integrated circuit memory device has a storage array with an adjustable number of memory banks, a row of sense amplifiers to access storage cells in the storage array; and memory access control circuitry. The memory access control circuitry provides a first number of memory banks and a first page size in the integrated circuit memory device in a first mode of operation, and provides a second number of memory banks and a second page size in the integrated circuit memory device in a second mode of operation. The memory access control circuitry includes logic circuitry to adjust the number of memory banks in the integrated circuit memory device, and to adjust the page size of the integrated circuit memory device.

Integrated circuit memory device having dynamic memory bank count and page size

A pulse multiplexed output subsystem is disclosed. In one particular exemplary embodiment, the output subsystem may comprise a plurality of pulse generators, a first pair of transistors, and a second pair of transistors, wherein each of the first pair of transistors is coupled to a respective one of a first pair of the plurality of pulse generators, and wherein each of the second pair of transistors is coupled to a respective one of a second pair of the plurality of pulse generators. The output subsystem may also comprise a first pair of resistive loads, wherein each of the first pair of resistive loads is coupled to a respective one of the first pair of transistors and a respective one of the second pair of transistors, and a first current source coupled to the first pair of transistors and the second pair of transistors.

Pulse multiplexed output system

A memory system includes a master device, such as a graphics controller or processor, and an integrated circuit memory device operable in dynamic memory bank count and page size mode. The integrated circuit memory device includes a first and second row of storage cells coupled to a row of sense amplifiers including a first and second plurality of sense amplifiers. During the first mode of operation, a first plurality of data is transferred from the first plurality of storage cells to the row of sense amplifiers. During the second mode of operation, a second plurality of data is transferred from the first row of storage cells to the first plurality of sense amplifiers and a third plurality of data is transferred from the second row of storage cells to the second plurality of sense amplifiers. The second and third plurality of data is accessible simultaneously from the memory device interface during the second mode of operation. In an embodiment, the second plurality of data is transferred from the first half of the first row and the third plurality of data is transferred from the second half of the second row.

Integrated circuit memory system having dynamic memory bank count and page size

An output driver has an output multiplexor and an output current driver. The output multiplexor receives a data signal and outputs a q-node signal. The output currentriver receives the q-node signal and drives a bus based on the q-node signal. The output multiplexor processes the data signal in various ways to generate the q-node signal. The output current driver is responsive to current control bits to select a amount of output drive current. In addition, the output multiplexor is controlled such that the output impedance of the output current driver is maintained within a predetermined range.

Impedance controlled output driver

An output driver has an output multiplexor and an output current driver. The output multiplexor receives a data signal and outputs a q-node signal. The output current driver receives the q-node signal and drives a bus based on the q-node signal. The output multiplexor processes the data signal in various ways to generate the q-node signal. The output current driver is responsive to current control bits to select a amount of output drive current. In addition, the output multiplexor is controlled such that the output impedance of the output current driver is maintained within a predetermined range.

Described are memory systems designed to emphasize differences between memory-cell access times. As a consequence of these access-time variations, data read from different memory cells arrives at some modified output circuitry. The output circuitry sequentially offloads the data in the order of arrival. Data access times are reduced because the output circuitry can begin shifting the first data to arrive before the slower data is ready for capture. Differences between data access times for cells in a given memory array may be emphasized using differently sized sense amplifiers, routing, or both.

DRAM output circuitry supporting sequential data capture to reduce core access times

Charge compensation control circuit and method for use with output driver

A current sensing, cascadable differential amplifier has a special bias circuit that provides a low impedance input and a high impedance output, whereby plural stages may be connected in cascade. Optionally, active current sources are used as pull-ups for the data lines, to increase the output impedance and improve the data line common mode level. The amplifier performs as a current sensing sense amplifier in a large scale, fast access semiconductor means and in this application, the memory does not need equalizing clock signals, nor is the access time slowed materially in the plural cascade stages.

SRAM with current-mode test read data path

A test circuit for a single chip semiconductor memory array, located in the chip, enables testing of all columns along a word lines without additional column readout circuits. A pair of current detecting differential amplifiers are connected to the bit lines of multiple memory cells along a word line, and the amplifier outputs are compared to generate a pass/fail signal during a read access.

Current mode test circuit for SRAM

An output buffer comprises a reference circuit having a plurality of reference transistors connected in parallel to each other and a output driver circuit having a corresponding plurality of driver transistors connected in parallel with each other. The reference transistors and the driver transistors both have varying widths with the widths of the reference transistors being a binary fraction, for instance one fourth, smaller than the widths of the corresponding output driver transistors. The transistors in the reference circuit are selectively conducted in order to match an impedance of the reference transistors to the impedance of a user selected resistor, representing a fraction of the impedance of a transmission line. The selection of the reference transistors also determines the selection of the driver transistors and consequently causes the impedance of the output driver to match the impedance of the transmission line. The reduction of the reference circuit by the binary fraction reduces the size of the overall circuit, lowers power consumption, and allows a matched layout between the transistors of the output driver and the reference circuit.

Binary weighted reference circuit for a variable impedance output buffer

A current sensing, cascadable differential amplifier has a special bias circuit that provides a low impedance input and a high impedance output, whereby plural stages may be connected in cascade. Optionally, active current sources are used as pull-ups for the data lines, to increase the output impedance and improve the data line common mode level. The amplifier performs as a current sensing sense amplifier in a large scale, fast access semiconductor memory and in this application, the memory does not need equalizing clock signals, nor is the access time slowed materially in the plural cascade stages.

SRAM with current-mode read data path

In a single chip semiconductor memory, having independent memory areas for normal memory cells and redundant memory cells, the redundant cells are tested in a parallel or multi-bit test mode simultaneously with the normal cells they replace, by enabling the redundant memory area in response to simultaneous detection of the state of the multi-bit test mode, the presence of a programmed redundant bit for a memory cell under test, and the operative selection of the normal memory matrix.

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San Carlos, CA, United States of America

Kurt T Knorpp