Abstract: Disclosed is a semiconductor memory device in which two sorts of series-connected transfer gates, that is, even-numbered and odd-numbered transfer gates are provided in series with each other between the ends of neighboring bit lines of a memory cell array connecting to bit lines of a sense amplifier. A first bit line of the sense amplifier is connected to a connection node of two, that is, even and odd, transfer gates between two bit lines of the memory cell array. A second bit line of the sense amplifier is connected to a connection node of two, that is, even and odd, transfer gates between two bit lines of the memory cell array. The two sorts of the transfer gates are controlled so that one of bit lines of a bit line pair of the sense amplifier will for all time become the signal side bit line.

Abstract: A semiconductor memory device comprising a substrate, a memory electrically connected to the substrate, a first and a second transmission/reception units transmitting a signal supplied by the memory and receiving a signal to be supplied to the memory, both arranged on a surface of the substrate, a branch circuit which is electrically connected to the first and the second transmission/reception units, and electrically discriminates the second transmission/reception unit from the memory, and a conversion circuit which converts the signal between the branch circuit and the memory into a signal in a predetermined format.

Abstract: Disclosed is a semiconductor memory device capable of realizing reduction in an SRAM unit cell area. Using as a standard configuration a parallel-type SRAM unit cell having each pair of load transistors, driver transistors and transfer transistors, all or a part of the gate electrodes and active regions configuring at least any one of the pairs of the transistors, for example, the pair of the transfer transistors are configured obliquely in a predetermined direction from the standard configuration. As a result, a size in a cell outside part including the driver transistor and the transfer transistor is reduced. At the same time, a distance between the load transistors in the central part is reduced as compared with that in the standard configuration. Thus, area reduction in the whole SRAM unit cell is realized.

Abstract: A ferroelectric memory includes: a memory cell having a ferroelectric capacitor, wherein, in a read-out operation, a first signal Q1 is given when a first voltage is applied to the ferroelectric capacitor, and a second signal Q2 is given when a second voltage having an identical magnitude as a magnitude of the first voltage in a different polarity is applied to the ferroelectric capacitor, and a judgment is made that the memory cell stores first data when Q1/Q2 is greater than 1/2, and second data when Q1/Q2 is smaller than 1/2.

Abstract: A static random access memory (SRAM) circuit includes first SRAM cell and a second SRAM cell that are configured to operate in a shared mode and/or an independent mode. In one example, a shared mode includes the sharing of a memory node of a first SRAM cell. In another example, an independent mode includes isolating a first SRAM cell from a second SRAM cell such that they operate independently.

Abstract: A magnetic memory includes a plurality of magnetoresistive elements which include a fixed layer in which a magnetization direction is fixed, a free layer in which a magnetization direction changes, and a nonmagnetic layer formed between the fixed layer and the free layer, and a word line electrically connected to the magnetoresistive elements. Data erase is performed by setting the magnetization direction of the free layer in a first direction by a magnetic field induced by a current flowing through the word line, and data of the magnetoresistive elements are erased by one time data erase. Data write is performed by setting the magnetization direction of the free layer in a second direction by spin-transfer magnetization reversal by supplying a current in one direction to the magnetoresistive elements.

Abstract: An end of a selected bit line in a selected column is electrically coupled to an end of a corresponding current return line by one of first and second write column select gates, which are selectively turned on in response to results of column selection. A data write circuit sets the other end of the selected bit line and the other end of the current return line to one and the other of a power supply voltage and a ground voltage in accordance with a level of write data via one of first and second data buses and an inverted data bus, respectively.

Abstract: A memory cell and method for making a memory cell in accordance with embodiments of the present invention includes two or more tunnel diodes, a loading system, and a driving system. The two or more tunnel diodes are coupled together, the loading system is coupled to the tunnel diodes and the driving system is coupled to the tunnel diodes and the loading system. The driving system drives a sense node from the tunnel diodes, the loading system, and the driving system between at least three or more substantially stable logic states.

Abstract: A system having a memory cell. In certain embodiments, the memory cell includes a resistive memory element, an access transistor having a gate, a first terminal, and a second terminal, and a control transistor having a gate, a first terminal, and a second terminal. The first terminal of the access transistor may be coupled to the resistive memory element, and the gate of the access transistor may be coupled to the gate of the control transistor. Additionally, the first terminal of the control transistor may be coupled to the resistive memory element.

Abstract: Normal memory cells are arranged in rows and columns, and dummy memory cells are arranged to form dummy memory cell rows by sharing memory cell columns with the normal memory cells. When there is at least one defect in the normal memory cells and/or the dummy memory cells, replacement/repair is carried out using a redundant column in a unit of memory cell column. The redundant column includes not only spare memory cells for repair of the normal memory cells but also spare dummy memory cells for repair of the dummy memory cells.

Abstract: The present invention presents a number of methods for identifying cells with poor subthreshold slope and reduced transconductance. A first set of techniques focuses on the poor subthreshold behavior of degraded storage elements by cycling cells and then programming them to a state above the ground state and the reading them with a control gate voltage below the threshold voltage of this state to see if they still conduct. A second set of embodiments focuses on weak transconductance behavior by reading programmed cells with a control gate voltage well above the threshold voltage. A third set of embodiments alters the voltage levels at the source-drain regions of the storage elements. The current-voltage curve of a good storage element is relatively stable under this shift in bias conditions, while degraded elements exhibit a larger shift. The amount of shift can be used to differentiate the good elements from the bad.

Abstract: A memory device is described that uses extra data bits stored in a multi-level cell (MLC) to provide error information. An example embodiment provides a memory cell that uses more than 2X logic levels to store X data bits and an error bit. At least one extra bit provided during a read operation is used to provide error information or a confidence factor of the X data bits originally stored in the cell.

Abstract: A flash memory system includes a multi level cell (MLC) flash memory organized into blocks and having pages of information, which has data and spare. The MLC flash memory includes at least a temporary area to store at least a portion of a page of information during a partial write operation. The MLC flash memory stores a page of information into a block identified by a target physical address. The flash memory system further includes a flash card micro-controller causes communication between a host flash card controller and the MLC flash memory and includes a buffer memory configured to store a portion of a page of information, where the micro-controller writes the at least a portion of a page of information to the temporary area and later copies the written at least a portion of a page of information into the block identified by a target physical address.

Abstract: An electrically alterable non-volatile multi-level memory device and a method of operating such a device, which includes setting a status of at least one of the memory cells to one state selected from a plurality of states including at least first to fourth level states, in response to information to be stored in the one memory cell, and reading the status of the memory cell to determine whether the read out status corresponds to one of the first to fourth level states by utilizing a first reference level set between the second and third level states, a second reference level set between the first and second level states and a third reference level set between the third and fourth level states.

Abstract: A semiconductor integrated circuit device is provided on a semiconductor substrate, and includes a plurality of word lines, a plurality of data lines, and a plurality of electrically programmable and erasable non-volatile memory cells respectively coupled to the plurality of word lines and to the plurality of data lines. The erasable non-volatile memory cell each includes a MIS transistor having a floating gate having a first level polycrystalline silicon layer, a source, and a drain coupled to the corresponding data line, and a control gate formed of a semiconductor region in the semiconductor substrate, the control gate being coupled to the corresponding word line.

Abstract: A memory device includes a layer of material structure and a plurality of memory cells each formed using a corresponding different portion of the layer. Each memory cell is constructed and designed to change a material property of the corresponding portion of the layer upon application of an electrical write signal. The memory device includes circuitry for outputting a signal indicating presence or absence of a change of the material property in the memory cells.

Abstract: Circuits, methods, and apparatus that provide waveforms having controlled rise and fall times, as well as accurate peak voltages. One embodiment provides circuitry for generating a clock signal and a current that are adjusted for an on-chip capacitance variation. This current is then used to generate rising and falling edges of a waveform. The clock signal is used to determine timing of transitions in the waveform. A bandgap or similar reference voltage is used to determine the peak voltage. This waveform is then gained using an amplifier circuit, and the output of the amplifier circuit is used as a programming voltage waveform for an EE-PROM. One embodiment further uses non-overlapping clocks to drive a charge pump that is used to generate a supply voltage for the amplifier circuit that far exceeds the available on-chip supply voltages.

Abstract: A memory cell in flash memory device is provided which includes a memory cell transistor having a control gate coupled to a word line and a drain coupled to a bit line; and a selection transistor for connecting a source of the memory cell transistor and a common source line in response to a selection signal.

Abstract: In a flash memory device, different self-boosting techniques are selectively applied to a string of serially connected memory cells responsive to a programming voltage applied to a selected word line. For example, non-local self-boosting and local self-boosting may be selectively applied responsive to the programming voltage applied to the selected word line. For example, non-local self-boosting and local self-boosting may be selectively applied to a first string of serially-connected cells responsive to the programming voltage during an incremental step pulse programming (ISPP) of a selected cell of a second string of serially-connected cells.

Abstract: A memory device including a memory cell array with information cells and reference cells arranged and a sense amplifier configured to sense data stored in the memory cell array, wherein the sense amplifier has a latch-type of differential amplifier configured to detect a current difference between a selected information cell and a selected reference cell, a pair of transistors attached to the differential amplifier, the pair of transistors being on-driven to keep the differential amplifier inactive in a stationary state and off-driven to make the differential amplifier active at a sensing time, whereby the current difference is amplified as a drain voltage difference of the pair of transistors, and a pair of capacitors hold voltages corresponding to the respective currents of two current paths of the differential amplifier prior to inputting the current difference, and apply a certain offset voltage to the pair of transistors at the sensing time.

Abstract: A nonvolatile semiconductor memory that improved a read rate. In a memory cell array in which each memory cell includes two storage areas, thresholds of outer storage areas of two memory cells which are symmetrical with respect to two adjacent bit lines are set so as to create a pair relation between them. A word line selection circuit applies read voltage to a word line to which the two memory cells to be read are connected. A bit line selection circuit applies ground voltage to two bit lines just outside the two memory cells and applies predetermined read voltage to two bit lines inside the two memory cells. A read conversion circuit compares drain currents which run through the two memory cells activated by the word line selection circuit and the bit line selection circuit, and converts the drain currents into data.

Abstract: A method of erasing a block of flash memory cells by applying a ramped gate erase voltage to the block of memory cells. When an erase verify of the block of memory cells indicates that erasure has not been successfully completed another erase voltage with a greater absolute value than the initial erase voltage can be applied to the block of memory cells until erasure is complete.

Abstract: Disclosed is a non-volatile memory device and a method of erasing the non-volatile memory device. An erase voltage is simultaneously applied to a plurality of sectors contained in the non-volatile memory device. Then, erase validation is sequentially performed for each of the plurality sectors and results of the erase validation are stored in a plurality of pass information registers. According to the results stored in the pass information registers, sectors which were not successfully erased are simultaneously re-erased and then sequentially re-validated until no such “failed sectors” remain in the non-volatile memory device. Upon eliminating the “failed sectors” from the non-volatile memory device, a post-program operation is sequentially performed on each of the plurality of sectors.

Abstract: A semiconductor storage device is capable of discriminating information stored in memory cells with high accuracy even if a gap that separates distributions of cell current values between data 0 and data 1 among a plurality of memory cells in a memory cell array becomes extremely narrow or overlapped with each other. A first memory cell MC11 and a second memory cell MC2 are adjacent to each other, and a first bit line BL1 to which a first input/output terminal of the first memory cell MC11 is connected as well as a second bit line BL2 to which a second input/output terminal of the second memory cell MC12 is connected are connected to inputs of a sense amplifier SA1, respectively. A second input/output terminal of the first memory cell MC11 and a first input/output terminal of the second memory cell MC12 are connected to a common line COM.

Abstract: A circuit and method are provided for controlling the gate voltage of a transistor acting between local and global input/output lines of a memory device, the circuit including a local input/output line, a local from/to global input/output multiplexer in signal communication with the local input/output line, a global input/output line in signal communication with the local from/to global input/output multiplexer, and a local from/to global input/output controller having an input node and an output node, the input node disposed for receiving a signal indicative of an input or output operation, and the output node in signal communication with a gate of the local from/to global input/output multiplexer for providing a gate signal of a first or second level in the presence of the output operation, and a gate signal of a third level in the presence of the input operation.

Abstract: A semiconductor device has at least two semiconductor memory devices, each of which includes a memory cell array arranged in a matrix of rows and columns, a peripheral circuit writing data to a cell of the memory cell array and reading out and amplifying the written data, and an output buffer outputting cell data amplified by the peripheral circuit. The output buffer includes an output buffer initialization circuit activating an output buffer reset signal in response to the power up or power down of the semiconductor memory device and deactivating the output buffer reset signal in response to a first command signal output from a controller of the semiconductor memory device, and an output driver generating output data based on a data signal in response to a clock signal, a data enable signal, and the output buffer reset signal.

Abstract: The present invention solves a problem of the degradation of the long-term reliability of a conventional semiconductor memory device due to early deterioration of a FET included in a reference cell therein. DRAM 1 has word lines 101 to 10n, word lines 22 and 24, memory cells 301 to 30n and a reference cell 40. Gates of FETs 32 in the memory cells 301 to 30n are connected to the word lines 101 to 10n respectively. Gates of a FET 42 and a FET 44 in the reference cell 40 are connected to the word line 22 for readout and the word line 24 for writing respectively. Here, potentials applied to the word lines 22 and 24 are lower than those applied to the word lines 101 to 10n.

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 semiconductor memory includes a plurality of memory cells, each of which includes a first inverter connected to one of high-data retaining supply lines which constitute one of high-data retaining supply line pairs corresponding to the memory cell and a second inverter connected to the other one of the high-data retaining supply lines which constitute the corresponding high-data retaining supply line pair, an input and output of the second inverter being connected to an output and input of the first inverter, respectively. A selected high-data retaining supply circuit receives a signal determined according to an input data signal and address signal without the intervention of any of the bit lines which constitute the bit line pairs to drive the connected high-data retaining supply lines such that it has a potential corresponding to the received signal.

Abstract: A memory has a novel self-timing circuit that generates internal memory control signals. Control signals may include an address latch enable signal, a decoder enable signal, and a sense amplifier enable signal. The circuit has a timing loop whose timing mimics the timing of an access of the real memory. The timing loop includes dummy bit cells of identical construction to bit cells in the real array being accessed, a programmable delay circuit, and a programmable accelerator circuit. The dummy bit cells cause the timing of the control signals to track speed changes in the memory array being accessed. The programmable delay and accelerator circuits are usable to slow or speed the timing loop. The programmable delay and accelerator circuits are usable to achieve a desired yield to memory access speed tradeoff. Flexibility of the timing loop allows a memory to be designed before memory access timing characteristics are fixed.

Abstract: A memory array for an integrated circuit includes a plurality of memory elements includes at least one redundant memory element for exchanging with a failed memory element in the plurality of memory elements. A failing address repair register is provided, having a register for controlling enablement of a corresponding redundant memory element and compare logic for determining whether an address of a failing memory element is stored in the register.

Abstract: An apparatus for testing a memory of an integrated circuit for a defect. The apparatus includes a test unit for testing a redundant memory element only when the redundant memory element has been enabled to replace a failed memory element.

Abstract: Methods and apparatuses for enabling a redundant memory element (20) during testing of a memory array (14). The memory array (14) includes general memory elements (18) and redundant memory elements (20). The general memory elements (18) are tested and any defective general memory elements (18) are replaced with redundant memory elements (20). The redundant memory elements (20) are tested only when they are enabled.

Abstract: An apparatus and method for repairing a semiconductor memory device includes a first memory cell array, a first redundant cell array and a repair circuit configured to nonvolatilely store a first address designating at least one defective memory cell in the first memory cell array. A first volatile cache stores a first cached address corresponding to the first address designating the at least one defective memory cell. The repair circuit distributes the first address designating the at least one defective memory cell of the first memory cell array to the first volatile cache. Match circuitry substitutes at least one redundant memory cell from the first redundant cell array for the at least one defective memory cell in the first memory cell array when a first memory access corresponds to the first cached address.

Abstract: In one form a memory and method thereof has a memory array having a plurality of memory cells. A bit line precharge operation is based on a clock edge of an external clock signal. A word line is selected after the beginning of the precharge operation. A sense operation is begun after enabling the word line, where the sense operation is for sensing a logic state of a memory cell. A data bit is output from the memory array corresponding to the sensed logic state of the memory cell. In one form the bit line precharge operation further comprises the bit line precharge operation having a predetermined duration that is independent of the clock signal, and the sense operation begins a predetermined delay time after enabling the word line, the sense operation having a variable duration.

Abstract: Each memory block has a plurality of memory cells, and word lines and bit lines connected to the memory cells. Precharge switches connect the bit lines to a precharge line. A switch control circuit controls an operation of the precharge switches and sets a cutoff function that turns off connection switches in a standby period in which no access operation of the memory cells is performed. Since connections of the bit lines and the precharge switch and those of the bit lines and the sense amplifier are cut off in the standby period, if a short circuit failure is present between a word line and a bit line, a leak current can be prevented from flowing from the word line to a precharge voltage line and so on.

Abstract: A sense amplifier circuit and a method for reading a memory cell. A circuit comprises a first bit line associated with a memory cell. A first input of a latch is coupled to the first bit line and a second input of the latch is coupled to a second node. There is a means for biasing the first input and the second input of the latch to a differential voltage between the first node coupled to the first bitline and the second node. There is also a means for switching the latch according to memory cell current. There is also a means for producing an output signal indicating the direction of switch. A method of reading a memory cell comprises precharging a first bit line which is associated with a memory cell. The memory cell current is driven according to the programmed state of the memory cell. Latch circuitry is biased based on a differential voltage between a first node coupled to the first bit line and a second node.

Abstract: Methods and a circuit for writing to an SRAM memory cell of an array are discussed that provide improved static noise margin, and minimal risk of data upsets during write operations. The write method first rapidly raises the wordline to a lower read voltage level for access, then after a time delay that allows the cells in the selected row to establish a stabilizing differential voltage on the associated bitlines, raises the wordline voltage to a boosted or higher write voltage level. An SRAM bitline enhancement circuit may also be utilized in association with the SRAM memory array and writing method, for enhancing the differential voltage produced by an SRAM memory cell of the array on associated first and second bitlines of the array of conventional SRAM cells (e.g., a conventional 6T differential cell). In one implementation, the SRAM bitline enhancement circuit comprises a half-latch or a sense amplifier connected to associated bitline pairs of the array for amplifying the differential voltage.

Abstract: [Problems] To provide an electronic device for checking the logical format specifications of a recording medium by a nonvolatile semiconductor memory such as a flash EEPROM, and for warning a device user that the format specifications of a memory card do not consider the block constitution of the flash memory.

Abstract: A method for adjusting a programming/erasing time in a memory system is disclosed. In one embodiment, a programming/erasing step is executed for writing data into the memory system, wherein the programming/erasing step is executed until a programming/erasing time and/or a cycle number per unit of time is reached. Then, a verification step is executed for verifying the data written into the memory system to determine if the data written into the memory system is correct so as to obtain a verification result. When the verification result is incorrect, a setting step is executed for setting the programming/erasing time and/or the cycle number per unit to new values. Thereafter, the programming/erasing step is repeatedly executed for writing the data into the memory system after the programming/erasing time and/or a cycle number per unit of time is set to the values.

Abstract: A three-dimensional solid-state memory is formed from a plurality of bit lines, a plurality of layers, a plurality of tree structures and a plurality of plate lines. Bit lines extend in a first direction in a first plane. Each layer includes an array of memory cells, such as ferroelectric or hysteretic-resistor memory cells. Each tree structure corresponds to a bit line, has a trunk portion and at least one branch portion. The trunk portion of each tree structure extends from a corresponding bit line, and each tree structure corresponds to a plurality of layers. Each branch portion corresponds to at least one layer and extends from the trunk portion of a tree structure. Plate lines correspond to at least one layer and overlap the branch portion of each tree structure in at least one row of tree structures at a plurality of intersection regions.

Abstract: Disclosed is a method of repairing an integrated circuit of the type comprising of a multitude of memory arrays and a fuse box holding control data for controlling redundancy logic of the arrays. The method comprises the steps of providing the integrated circuit with a control data selector for passing the control data from the fuse box to the memory arrays; providing a source of alternate control data, external of the integrated circuit; and connecting the source of alternate control data to the control data selector. The method comprises the further step of, at a given time, passing the alternate control data from the source thereof, through the control data selector and to the memory arrays to control the redundancy logic of the memory arrays.

Abstract: An integrated circuit chip having programmable functions and features in which one-time programmable (OTP) memories are used to implement a non-volatile memory function, and a method for providing the same. The OTP memories may be based on poly-fuses as well as gate-oxide fuses. Because OTP memories are small, less die area is utilized as compared to metal fuses. Additionally, because OTP memories can be implemented as part of standard complementary metal oxide semiconductor (CMOS) processes, the method is less costly and complex than the use of electrically-erasable programmable read-only memories (E2PROMs).

Abstract: A combo semiconductor memory apparatus capable of reducing current and power consumption is provides. The semiconductor memory apparatus includes: a signal generator that generates a voltage control signal according to the level of an external voltage; and a voltage generator that pumps up the level of the external voltage in response to the voltage control signal and outputs the pumped voltage to a high-level voltage output terminal, or supplies the external voltage as a high-level voltage.

Abstract: A memory circuit power management system and method are provided. In use, an interface circuit is in communication with a plurality of memory circuits and a system. The interface circuit is operable to interface the memory circuits and the system for performing a power management operation in association with at least a portion of the memory circuits. Such power management operation is performed during a latency associated with one or more commands directed to at least a portion of the memory circuits.

Abstract: A memory device includes at least one memory array having a plurality of memory cells addressed by a plurality of word lines and bit lines, and coupled between a power line and a ground line. A word line decoder is coupled to one end of the word line for selecting the word lines in response to input signals. A voltage control circuit is coupled to another end of the word line for connecting the word line to a ground voltage when the memory device is in a sleep mode, wherein the voltage control circuit is supplied by DC power.

Abstract: A semiconductor device whose operation frequency and power supply voltage are dynamically controlled according to a load subjected to a process to be performed is disclosed. The semiconductor device includes a memory cell array having SRAM cells arranged in an array form, word lines connected to the SRAM cells for respective rows, a row decoder which selects the word lines one by one during normal operation and multi-select word lines which are not adjacent to each other during low-voltage operation, a load circuit which sets the level of the selected word line to potential lower than power supply voltage, and a controller which controls the row decoder and load circuit to selectively control selection of the word lines and the load circuit.

Abstract: A semiconductor memory device of the invention comprises unit blocks into which the memory cell array is divided, rows of sense amplifiers arranged at one end and the other end of the plurality of bit lines in the unit block, switch means for switching a connection state between the unit block and the row of sense amplifiers attached to the unit block; and control means for controlling the switch means so as to form a transfer path from the row of sense amplifiers attached to a predetermined the unit block leading to the row of sense amplifiers as a saving destination not attached to the predetermined the unit block. This row of sense amplifiers attached to the predetermined the unit block functions as a cache memory.

Abstract: A double-rate memory has an array of single word line memory cells arranged in rows and columns. The single word line memory cells provide and store data via a first port. Addressing and control circuitry is coupled to the array of single word line memory cells. The addressing and control circuitry receives an address enable signal to initiate an access of the array whereby an address is received, decoded, and corresponding data retrieved or stored. Edge detection circuitry receives a memory clock and provides the address enable signal upon each rising edge and each falling edge of the memory clock to perform two memory operations in a single cycle of the memory clock. A memory operation includes addressing the memory and storing data in the memory or retrieving and latching data from the memory. In another form a double-rate dual port memory permits two independent read/write memory accesses in a single memory cycle.

Abstract: A driver power supply circuit stepping down a power supply voltage is arranged at a power supply node of a word line driver. The driver power supply circuit includes a non-silicide resistance element of N+ doped polycrystalline silicon, and a pull-down circuit lowering a voltage level of the driver power supply node. The pull-down circuit includes a pull-down transistor having the same threshold voltage characteristics as a memory cell transistor pulling down a voltage level of the driver power supply node, and a gate control circuit adjusting at least a gate voltage of the pull-down transistor. The gate control circuit corrects the gate potential of the pull-down transistor in a manner linked to variations in threshold voltage of the memory cell transistor.