Abstract: A Schmitt Trigger (ST) based, fully differential, 10-transistor (10T) SRAM (Static Random Access Memory) bitcell suitable for sub-threshold operation. The Schmitt trigger based bitcell achieves 1.56× higher read static noise margin (SNM) (VDD=400 mV) compared to a conventional 6T cell. The robust Schmitt trigger based memory cell exhibits built-in process variation tolerance that gives tight SNM distribution across the process corners. It utilizes fully differential operation and hence does not require any architectural changes from the present 6T architecture. The 10T bitcell has two cross-coupled Schmitt trigger inverters which each consist of four transistors, including a PMOS transistor and two NMOS transistors in series, and an NMOS feedback transistor which is connected between the inverter output and the junction between the series-connected NMOS transistors. Each inverter has one associated NMOS access transistor.

Abstract: A data I/O line control circuit includes a control unit for outputting a control signal after a predetermined time from an activation of a column select signal, and a switching unit for selectively separating a pair of first sub-middle I/O lines, which is coupled to a pair of local I/O lines located at one side of the switching unit, from a pair of second sub-middle I/O lines, which is coupled to both the pair of the local I/O lines and a data bus sense amplifier located at the other side of the switching unit.

Abstract: A semiconductor memory device is capable of writing data in phase with external data to a memory cell regardless of which memory cell the data is written to. The semiconductor memory device includes a scrambler, a write selector and a read selector. The scrambler is configured to output a control signal activated when an address for accessing a memory cell of a complementary bit line is inputted. The write selector is configured to selectively transmit data of a write path in response to the control signal. The read selector is configured to selectively transmit data of a read path in response to the control signal.

Abstract: In a multi-port register file of a storage unit within a processor, an improved bitcell design for storing a data bit is disclosed. The bitcell comprises a first set of read bitlines having a first load and a second set of read bitlines having a second load, in which the second load is substantially equal to the first load. The bitcell also comprises a signal driving circuit having a first node and a second node. The first node is connected to the first set of read bitlines and the second node is connected to the second set of read bitlines.

Abstract: A semiconductor includes a first sensor amplifier, a second sensor amplifier, a first switch and a second switch. The first sensor amplifier is coupled between a local data line and a memory unit to amplify signals of the memory unit. The second sensor amplifier is coupled to a middle data line to amplify signals of the middle data line. The first switch is coupled between the middle data line and the local data line to equalize voltage levels between the middle data line and the local data line by turning on the first switch according to a data control signal. The second switch is coupled between the local data line and a reference voltage to equalize the local data line to the voltage level of the reference voltage by turning on the second switch according to a local data control signal.

Abstract: A memory cell array includes memory cells disposed in a matrix. A plurality of word-lines are arranged in the memory cell array to select a memory cell in a row direction. A read bit-line pair is arranged in a direction perpendicular to the word-line to read data from the memory cell. In addition, a write bit-line is arranged in a direction perpendicular to the word-line to write data to the memory cell. The read bit-line pair includes a true and a complementary read bit-line. One of the true and complementary read bit-lines is connected to the memory cell connected to an even-numbered word-line. The other one is connected to the memory cell connected to an odd-numbered word-line.

Abstract: Methods and apparatus to provide ultra low voltage, low leakage, high density, and/or variation tolerant memory bit cells are described. In one embodiment, each of the cross-coupled invertors of a memory cell may include a plurality of p-channel transistors. Other embodiments are also described.

Abstract: Embodiments for an area efficient high performance memory cell comprising a transistor connected to one of a bit line and a bit line bar are disclosed.

Abstract: The semiconductor device includes a nonvolatile memory, having a memory array containing 1-bit twin cells, each composed of electrically rewritable first and second storage devices, the first and second storage devices holding binary data according to difference of their threshold voltages, and having different retention characteristics depending on difference of the binary data thereof; a read circuit for differentially amplifying complementary data output from the first and second storage devices of the twin cell selected for read, and judging information stored in the twin cell; and a control circuit. Two memory cells constituting a twin cell are arranged to hold different data. Therefore, even when the retention performance of one memory cell deteriorates, the difference between data held by the two memory cells can be maintained. Hence, differential amplification of such difference enables acquisition of proper stored information.

Abstract: A semiconductor device includes a first sense amplifier coupled to an input for generating a first output; a second sense amplifier couple to the input for generating a second output; and a third sense amplifier coupled to the input for generating a third output, wherein a fourth output amplifying the input is generated based on combinations of logic states of the first, second and third outputs.

Abstract: An operation control circuit carries out a first access operation upon receipt of a first access command during activation of a chip enable signal, and carries out a second access operation accessing a memory core in a shorter time than the first access operation, upon receipt of the next access command during activation of the chip enable signal. For this reason, two types of access operations whose access times differ can be carried out by receiving the same access command at the same access terminal. A dedicated terminal for distinguishing between the two types of operations does not need to be formed in a controller, etc., which accesses a semiconductor memory. Selective use of the first and second access operations improves the operation efficiency of the semiconductor memory. Consequently, the operation efficiency of the semiconductor memory can be improved without increasing the cost of a system incorporating the semiconductor memory.

Abstract: Methods and apparatus are provided. A memory device includes a first bit line selectively coupled to an input of a sensing device through a first multiplexer gate, and a second bit line selectively coupled to the input of the sensing device through a second multiplexer gate. The first bit line is formed at a first vertical layer and is coupled to a first source/drain region of the first multiplexer gate. The input of the sensing device is formed at a second vertical layer different than the first vertical layer and is coupled to a second source/drain region of the first multiplexer gate and a first source/drain region of the second multiplexer gate. The second bit line is formed at the first vertical layer and is coupled to a second source/drain region of the second multiplexer gate.

Abstract: One aspect of the invention relates to a method for accessing a memory device. One embodiment relates to a method for accessing a memory device. In the method during a read operation, one data value is provided on a local IO line while complimentary local IO line that is associated with the local IO line is inactivated. During a write operation, another data value is provided on the local IO line and a complimentary data value is provided on the complimentary local IO line. Other systems and methods are also disclosed.

Abstract: Various systems and methods for implementing memory devices are disclosed. For example, some embodiments of the present invention provide sub-threshold memory devices that include a differential bit cell. Such a differential bit cell includes two PMOS transistors, two NMOS transistors, and two inverters. The source of the first PMOS transistor and the source of the second PMOS transistor are electrically coupled to a bit line input, and the source of the first NMOS transistor and the source of the second NMOS transistor are electrically coupled to the bit line input. The gate of the first NMOS transistor and the gate of the second NMOS transistor are electrically coupled to a word line input. The gate of the first PMOS transistor and the gate of the second PMOS transistor are electrically coupled to an inverted version of the word line input.

Abstract: An SRAM device includes: a first group of memory cells connected to a first local bit line and a first local complementary bit line for accessing data nodes thereof; a second group of memory cells connected to a second local bit line and a second local complementary bit line for accessing data nodes thereof; and a global bit line and a global complementary bit line connected to the first and second local bit lines for accessing data nodes of the first and second groups of memory cells, wherein the first local bit line, the first local complementary bit line, the second local bit line, the second local complementary bit line, the global bit line and the global complementary bit line are constructed on a same metallization level in the SRAM device.

Abstract: A dynamic random access memory (DRAM) having pairs of bitlines, each pair being connected to a first bit line sense amplifier, wordlines crossing the bitlines pairs forming an array, charge storage cells connected to the bitlines, each having an enable input connected to a wordline, the bit line sense amplifiers being connected in a two dimensional array, pairs of primary databuses being connected through first access transistors to plural corresponding bit line sense amplifiers in each row of the array, apparatus for enabling columns of the first access transistors, databus sense amplifiers each connected to a corresponding data bus pair, a secondary databus, the secondary databus being connected through second access transistors to the databus sense amplifiers, and apparatus for enabling the second access transistors, whereby each the primary databus pair may be shared by plural sense amplifiers in a corresponding row of the array and the secondary databus may be shared by plural primary databus pairs.

Abstract: A method and apparatus including a static random access memory (SRAM) cell implement an enhanced SRAM read performance sort ring oscillator (PSRO), and a design structure on which the subject circuit resides is provided. A pair of parallel reverse polarity connected inverters defines a static latch or cross-coupled memory cell. The SRAM cell includes independent left and right wordlines providing a respective gate input to a pair of access transistors used to access to the memory cell. The SRAM cell includes a voltage supply connection to one side of the static latch. For example, a complement side of the static latch is connected to the voltage supply. A plurality of the SRAM cells is assembled together to form a SRAM base block. A plurality of the SRAM base blocks is connected together to form the SRAM read PSRO.

Abstract: A semiconductor memory device may include a power line, an over driver, and/or an internal voltage driver. The power line may be connected to at least one sense amplifier. The at least one sense amplifier may be connected to a memory cell included in a memory block. The memory block may be included in one of a plurality of memory block units including one or more memory blocks. The over driver may be configured to apply an external voltage to the power line in a sensing period of the sense amplifier. The internal voltage driver may be configured to apply an internal voltage to the power line in an amplification period of the sense amplifier. The over driver may be configured to perform an over driving operation by each memory block unit.

Abstract: Methods and apparatus relating ultra-low voltage memory bit cells are described. In an embodiment, an ultra-low voltage memory device is provided using redundant paths to data storage nodes controlled by complementary write word lines. Other embodiments are also described.

Abstract: A semiconductor memory device includes a sense amplifier for the FBC, a first node and a second node can be disconnected from each other by a first isolation transistor. A third node and a fourth node can be disconnected from each other by a second isolation transistor. The first node is connected to the first memory cell. The third node is connected to the second memory cell. A first amplification transistor and a second amplification transistor are connected between the first node and the third node. A third amplification transistor and a fourth amplification transistor are connected between the second node and the fourth node. This enables to parallelly execute read data transfer to the data lines and precharge to prepare for the next read operation.

Abstract: A data buffer, such as a data strobe input buffer or a data input buffer, which may operate in multiple modes, such as a single mode (SM) and a dual mode (DM) and where the mode is selected by providing a signal, such as an external signal such as an address signal or an external command signal. A data buffer which can be used for a SM/DM dual-use and can improve a data setup/hold margin. A semiconductor memory device including one or more of the data buffers described above. A method for controlling propagation delay times which can improve a data setup/hold margin in a SM/DM dual-use data buffer.

Abstract: Methods and apparatus provide for writing data into and reading data from an anti-parallel storage circuit of an SRAM memory cell via a true bit line (BLT) and a complementary bit line (BLC); and preventing the complementary bit line (BLC) from substantially dropping from a pre-charge, logic high voltage level during operations in which a logic low level is written into the anti-parallel storage circuit.

Abstract: A circuit and method for a sense amplifier for sensing the charge stored by a memory cell is disclosed. The memory cell is coupled to a bit line, a complementary bit line and a differential sense amplifier is coupled to the bit line and the complementary bit line. A control signal couples a reference voltage to the complementary bit line. A positive precharge voltage is applied to the bit line and complementary bit line prior to the sense amplifier being enabled. The memory cell outputs a voltage to the bit line responsive to a word line, and the sense amplifier senses the differential voltage between the bit line and the complementary bit line responsive to a sense enable signal. A voltage regulator for generating the reference voltage, preferably about 80% of a positive supply voltage, is disclosed. A method of sensing data stored by a memory cell is disclosed.

Abstract: A sense amplifier enable signal generator has two stages. Each stage offsets transistor performance variation in the other stage to produce an enable signal output relatively immune from the effects associated with transistor mismatches. In one embodiment, a memory device comprises a plurality of memory cells, sense amplifier circuitry and the enable signal generator. The sense amplifier circuitry is coupled to one or more of the memory cells and senses the state of the one or more memory cells when enabled. The enable signal generator has first and second stages and generates an enable signal applied to the sense amplifier circuitry. The enable signal generator counteracts delay variation when generating the enable signal so that operation of the enable signal generator is substantially unaffected by transistor performance variation in either stage of the enable signal generator.

Abstract: A data amplifying circuit for a semiconductor integrated circuit including a controller configured to generate a control signal for adjusting an amplification step in response to a test signal, and a data amplifier configured to amplify an input signal one time or two or more times in response to the control signal and to output an output signal.

Abstract: Voltage coupling/decoupling devices are provided within DRAM devices for improving the bias sensing of sense amplifiers and thus the refresh performance. The voltage coupling/decoupling devices couple or decouple bias voltage from corresponding digit lines coupled to the sense amplifiers. By coupling and decoupling voltage from the digit lines, the time interval between refresh operations can be increased.

Abstract: A multi-level dynamic memory device having an open bit line structure is disclosed. The multi-level dynamic memory device includes a plurality of word lines; a plurality of bit lines provided in an open bit line structure; a plurality of memory cells each of which is connected to each of the word lines and each of the bit lines and stores at least two bits of data; and a plurality of sense amplifiers, each of which amplifies a voltage difference between the bit lines, the bit lines being located at opposite sides of each of the plurality of sense amplifiers.

Abstract: A semiconductor memory device includes a selector line selection circuit for selecting, in a read operation, a selector line for connecting a first main bit line connected to the sense amplifier with a sub-bit line to which the memory cell being read is connected, a selector line for connecting the first main bit line with a sub-bit line of at least one sector different from the sector to which the memory cell being read belongs, a selector line for connecting a second main bit line connected to the sense amplifier with a sub-bit line to which the reference cell is connected, and a selector line for connecting the second main bit line with a sub-bit line of at least one sector different from the sector to which the memory cell being read belongs.

Abstract: A nanotube-based switching element includes an input node, an output node, and a nanotube channel element having at least one electrically conductive nanotube. A control structure is disposed in relation to the nanotube channel element to controllably form and unform an electrically conductive channel between said input node and said output node. The output node is constructed and arranged so that channel formation is substantially unaffected by the electrical state of the output node. The control structure includes a control electrode and a release electrode, disposed on opposite sides of the nanotube channel element. The control and release may be used to form a differential input, or if the device is constructed appropriately to operate the circuit in a non-volatile manner. The switching elements may be arranged into logic circuits and latches having differential inputs and/or non-volatile behavior.

Abstract: A semiconductor memory apparatus includes a plurality of unit cell blocks formed in row and column directions, at least a pair of first input and output lines formed at predetermined intervals in the row direction, at least a pair of second input and output lines formed at predetermined intervals in the column direction, I/O switches connected to a first node group and a second node group and control data input and output of the first input and output lines and the second input and output lines, the first node group corresponding to half of the nodes in the row direction where the first input and output lines intersect the second input and output lines formed at the odd-numbered intervals of the intervals between columns of unit cell blocks, and the second node group corresponding to half of the nodes in the row direction where the first input and output lines intersect the second input and output lines formed at the even-numbered intervals of the intervals between columns of unit cell blocks and a reset sele

Abstract: Asymmetrical random access memory cell (1) including cross coupled inverters (2, 3) which are driven at their nodes (22, 32) by separate bit-lines (blt, blc) of a pair of complementary bit-lines, which are connected via a pass-transistor (21, 31), wherein the random access memory cell is asymmetrical by means of the cross coupled inverters (2, 3) which have asymmetrically physical behaviours whereby different switching thresholds of the inverters are present, and that the pass-transistors (21, 31) are driven by separate controlled wordlines (wl, wwl).

Abstract: A semiconductor memory device of the present invention provides, in a memory having an hierarchical bit line structure, a test mode which causes all switches for selecting hierarchical bit lines and a main bit line in an activated memory array to be connected all the time. With this configuration, it is possible to perform a disturb refresh test on a memory cell arrays basis regardless of the hierarchical bit line structure. Possibility of an erroneous read-out, which may be caused by connecting each of the hierarchical bit lines to one another and a consequent increase in a bit line load capacity, may be prevented by providing a timing control such that the switches are connected after a normal mode operation.

Abstract: An SRAM device includes: a first group of memory cells connected to a first local bit line and a first local complementary bit line for accessing data nodes thereof; a second group of memory cells connected to a second local bit line and a second local complementary bit line for accessing data nodes thereof; and a global bit line and a global complementary bit line connected to the first and second local bit lines for accessing data nodes of the first and second groups of memory cells, wherein the first local bit line, the first local complementary bit line, the second local bit line, the second local complementary bit line, the global bit line and the global complementary bit line are constructed on a same metallization level in the SRAM device.

Abstract: Storage circuits (180-183 and 280-281) may be used for low power operation while allowing fast read access. In one embodiment (e.g. circuit 100), shared complementary write bit lines (101, 102), separate read bit lines (103-106), a shared read word line (107), and separate write word lines (108-111) are used. In an alternate embodiment (e.g. circuit 200), shared complementary write bit lines (201, 202), a shared read bit line (203), separate read word lines (206-207), and separate write word lines (208-209) are used. The storage circuit may be used in a variety of contexts, such as, for example, a register file (17), a branch unit (15), an SRAM (19), other modules (20), a cache (18), a buffer (21), and/or a memory (14).

Abstract: A data buffer, such as a data strobe input buffer or a data input buffer, which may operate in multiple modes, such as a single mode (SM) and a dual mode (DM) and where the mode is selected by providing a signal, such as an external signal such as an address signal or an external command signal. A data buffer which can be used for a SM/DM dual-use and can improve a data setup/hold margin. A semiconductor memory device including one or more of the data buffers described above. A method for controlling propagation delay times which can improve a data setup/hold margin in a SM/DM dual-use data buffer.

Abstract: An input buffer generates an output signal corresponding to a digital input signal. The input buffer is coupled to a feedback circuit. The feedback circuit initially couples a positive feedback signal to the buffer circuit responsive to each transition of the input signal. The positive feedback signal increases the gain of the input buffer thereby causing the input buffer to transition the output signal more quickly in response to the transition of the input signal. The feedback circuit thereafter terminates the positive feedback signal before a subsequent transition of the input signal. The positive feedback signal is generated by detecting a transition of the output signal responsive to the transition of the input signal that initiated the positive feedback signal.

Abstract: Implementations are presented herein that relate to a memory cell, a memory device, a device and a method of accessing a memory cell.

Abstract: An early write with data masking technique for dynamic random access memory (DRAM) devices and those devices incorporating embedded DRAM. The technique of the present invention allows for early writes to DRAM arrays with direct bit, byte or word data masking capability.

Abstract: An improved memory system incorporates an array of memory cells that are subjected to minimal location dependent power variations and, optionally, allows for bi-directional random access of millions of bits. The system architecture provides a consistent amount of bit line resistance in the write and read paths to each memory cell in the array, independent of position, in order to minimize variations in power delivery to the cells and, thereby, allow for optimal cell distributions. The system architecture further allows current to pass in either direction through the cells in order to minimize element electro-migration and, thereby, extend memory cell life.

Abstract: There is provided a bit line voltage supply circuit for reducing leakage current flowing from bit lines to a memory cell without substantially deteriorating the performance of a semiconductor memory device. A bit line voltage switch applies a first supply voltage to a bit line pair in response to a first switch control signal, and applies a second supply voltage having a lower voltage than the first supply voltage to the bit line pair in response to a second switch control signal. A bit line voltage controller controls the first and second switch control signals so that the second supply voltage is supplied to the bit line pair during a standby mode, and the first supply voltage is supplied to the bit line pair when the semiconductor memory device changes from the standby mode to an operational mode for a predetermined time period.

Abstract: A column circuit that amplifies signals read from a sense amplifier array SAA to local input/output lines LIO in sub-amplifiers SAMP to transfer the amplified signals to main input/output lines MIO is provided. A current control circuit IC that can set one of two kinds of currents according to read enable signals RD1, RD2 is provided in each sub-amplifier SAMP. The read enable signals RD1, RD2 are generated at timings corresponding to the number of cycles in burst read operation under control of the timing controller. Current in the current control circuit IC is set to be large by the RD1 in burst read operation cycle just after activation of a memory bank, while current in the current control circuit IC is set to be small by the RD2 in the next and subsequent burst read cycles. Accordingly, expansion of an operation margin or reduction of power consumption can be realized in a semiconductor device including a semiconductor memory such as a DRAM.

Abstract: A dynamic random access memory (DRAM) having pairs of bitlines, each pair being connected to a first bit line sense amplifier, wordlines crossing the bitlines pairs forming an array, charge storage cells connected to the bitlines, each having an enable input connected to a wordline, the bit line sense amplifiers being connected in a two dimensional array, pairs of primary databuses being connected through first access transistors to plural corresponding bit line sense amplifiers in each row of the array, apparatus for enabling columns of the first access transistors, databus sense amplifiers each connected to a corresponding data bus pair, a secondary databus, the secondary databus being connected through second access transistors to the databus sense amplifiers, and apparatus for enabling the second access transistors, whereby each the primary databus pair may be shared by plural sense amplifiers in a corresponding row of the array and the secondary databus may be shared by plural primary databus pairs.

Abstract: Methods and apparatus provide for writing data into and reading data from an anti-parallel storage circuit of an SRAM memory cell via a true bit line (BLT) and a complementary bit line (BLC); and preventing the complementary bit line (BLC) from substantially dropping from a pre-charge, logic high voltage level during operations in which a logic low level is written into the anti-parallel storage circuit.

Abstract: A write circuit structure may be used to transfer data between global bit lines and local bit lines of a cache. The write circuit structure located between the hierarchical bit lines may be buffers in parallel with P-channel devices in one embodiment or cross-coupled P-channel and N-channel devices in another embodiment.

Abstract: A method and apparatus including a static random access memory (SRAM) cell implement an enhanced SRAM read performance sort ring oscillator (PSRO). A pair of parallel reverse polarity connected inverters defines a static latch or cross-coupled memory cell. The SRAM cell includes independent left and right wordlines providing a respective gate input to a pair of access transistors used to access to the memory cell. The SRAM cell includes a voltage supply connection to one side of the static latch. For example, a complement side of the static latch is connected to the voltage supply. A plurality of the SRAM cells is assembled together to form a SRAM base block. A plurality of the SRAM base blocks is connected together to form the SRAM read PSRO.

Abstract: A method and system for operating a DRAM device in either a high power, full density mode or a low power, half density mode. In the full density mode, each data bit is stored in a single memory cell, and, in the half density mode, each data bit is stored in two memory cells that are refreshed at the same time to permit a relatively slow refresh rate. When transitioning from the full density mode to the half density mode, data are copied from each row of memory cells storing data to an adjacent row of memory cells. The adjacent row of memory cells are made free to store data from an adjacent row by remapping the most significant bit of the row address to the least significant bit of the row address, and then remapping all of the remaining bits of the row address to the next highest order bit.

Abstract: Methods and apparatus provide for writing data into and reading data from an anti-parallel storage circuit of an SRAM memory cell via a true bit line (BLT) and a complementary bit line (BLC); and preventing the complementary bit line (BLC) from substantially dropping from a pre-charge level during operations in which a logic one is read from the anti-parallel storage circuit.

Abstract: A semiconductor memory device includes: a memory cell array region formed in a semiconductor region of a first conductivity type and having a plurality of memory cells arranged in rows and columns; a plurality of word lines each of which collectively connects ones of the plurality of memory cells aligned in the same row; and a protective diode region formed in the semiconductor region to be separated from the memory cell array region. In the protective diode region, a protective diode element is constructed by making a junction between a first diffusion layer of a second conductivity type formed in the upper portion of the semiconductor region and the semiconductor region. Each of the word lines extends to the protective diode region and is brought into direct connection to the first diffusion layer of the second conductivity type, thereby making electrical connection to the protective diode element.

Abstract: A system, method, and computer program product are provided for broadcasting write operations in a multiple-target system. In use, a write operation is received at one of a plurality of apertures of an address space. Such write operation is then replicated to produce a plurality of write operations. To this end, the write operations may be broadcasted to a plurality of targets. At least one of the targets includes another one of the apertures that produces at least one additional write operation.

Abstract: A domino SRAM global bit select circuit provides an interface between dual global read and write bit line pairs to a “local bit select” circuit.