Abstract: In the semiconductor memory device having a resistance memory element, a first transistor having a drain terminal connected to one end of the resistance memory element and a source terminal connected to a ground voltage, and a second transistor having source terminal connected to the resistance memory element, when a write voltage is applied to the resistance memory element via the second transistor to switch the resistance memory element from a low resistance state to a high resistance state, a voltage is controlled to be a value which is not less than a reset voltage and less than a set voltage by applying to a gate terminal of the second transistor a voltage which is not less than a total of the reset voltage and a threshold voltage of the second transistor and is less than a total of the set voltage and the threshold voltage.

Abstract: A sense amplifier includes a first sensing element and a second sensing element redundant to the first sensing element. The sense amplifier further comprises a switch circuit configured to switch between the first and second sensing elements when an offset of the sense amplifier is greater than a prescribed amount.

Abstract: A semiconductor storage device precharging a bit line pair to a ground potential includes a sense amplifier connected between the bit line pair, a storage cell connected to one of the bit line pair and storing data, a first transistor controlling a conduction state between the other of the bit line pair and a reference cell node, a second transistor connected between a reference voltage source generating a reference voltage and the reference cell node, the second transistor exclusively controlled from the first transistor, and a capacitor setting a potential of the reference cell node.

Abstract: A system for controlling asynchronous updates to a register, the system including a generally accessible register that is asynchronously updateable by hardware and software. The system also includes protection logic that is in communication with the register. The protection logic includes circuitry to prevent a hardware update to the register from being overwritten by a software update.

Abstract: Techniques for generating clock and control signals to achieve good performance for read and write operations in memory devices are described. In one design, a clock and control signal generator within a memory device includes first and second clock generators, first and second control signal generators, and a reset circuit. The first clock generator generates a first clock signal used for read and write operations. The second clock generator generates a second clock signal used for write operations. The reset circuit generates at least one reset signal for the first and second clock generators. The reset signal(s) may have timing determined based on loading due to dummy cells. The first control signal generator generates control signals used for read and write operations based on the first clock signal. The second control signal generator generates control signals used for write operations based on the second clock signal.

Abstract: A data retention monitor for a memory cell including a voltage source and a voltage comparator. The voltage source is adapted to provide a selectable voltage to the memory cell. The selectable voltage includes a read voltage and a test voltage, with the test voltage being greater than the read voltage. The voltage comparator is adapted to compare a voltage of the memory cell with a reference voltage after the provision of the selectable voltage to the memory cell. The memory cell retains data when the memory cell voltage generated at least in part by the test voltage is substantially equal to the reference voltage.

Abstract: Between the value of an electric current and the supply duration for which the electric current is supplied that cause magnetization reversal, there is the relation of monotonous decrease. This means that, as the supply duration is shortened, the threshold current value for causing the magnetization reversal is larger. Therefore, in terms of suppressing occurrence of read disturb, the read current supply duration may be shortened to increase the threshold value of the current causing the magnetization reversal and thereby ensure a sufficient read disturb margin. Therefore, the read current supply duration may be shortened relative to the write current supply duration ensure the read disturb margin and suppress occurrence of read disturb.

Abstract: In one embodiment, a semiconductor memory device includes a plurality of pairs of bit lines, each of said pairs including a first bit line, a second bit line, a memory cell coupled to said first bit line, a sense amplifier determining the logical value stored in the memory cell according to a potential difference between the first and the second bit line, a reference voltage generation circuit, and a reference voltage supply switch coupling an output of the reference voltage generation circuit to the second bit line.

Abstract: An apparatus for removing crosstalk in a semiconductor memory device includes pads for receiving externally provided signals, transmission lines for delivering the signals received by each of the pads to corresponding elements in the apparatus, and capacitors, coupled between adjacent ones of the lines, for adjusting the transmission delay of the signals depending on a signal transmission mode between the adjacent lines.

Abstract: Disclosed is a semiconductor memory device including a discharge circuit that discharges bit lines to a ground potential, a sense amplifier of a single-ended input configuration, and a charging transistor connected between a power supply and an input node of the sense amplifier. The charging transistor charges a bit line from a side of the input node of the sense amplifier via the selected column select transistor which is set to an on state. When a current path to the ground from the bit line to which a selected memory cell is connected is turned off at a time of reading, the input node of the sense amplifier is charged by the charging transistor, and a potential at the input node of the sense amplifier is thereby raised. Then, after the input node of the sense amplifier has been further charged with the one of the column select transistors turned off, the reading operation is performed.

Abstract: Method and apparatus for providing nonvolatile storage with a programmable transistor. The method includes receiving a data value to be stored in the programmable transistor and programming the programmable transistor to store the received data value. Programming includes applying a selected voltage to the programmable transistor. The selected voltage is selected to inject carriers into a gate oxide layer of the programmable transistor. The carriers are maintained in the gate oxide layer of the programmable transistor in the absence of the selected voltage, thereby programming the programmable transistor with the received data value.

Abstract: A circuit and method for a sense amplifier for sensing the charge stored when a select signal couples a memory cell to the sense amplifier. A pull up voltage and a pull down voltage are instantaneously supplied to the sense amplifier to sense the small signal differential input on the complementary bit lines and to simultaneously restore the value stored in the memory cell. A differential output signal generator circuit is provided to instantaneously supply the pull up and pull down voltages. In another preferred embodiment the signal generator provides the pull up and pull down voltages at a first level and subsequently increases the pull up voltage to a voltage greater than the positive supply voltage and decreases the pull down voltage. A method of sensing is disclosed wherein the sense and restore actions are performed instantaneously to provide memory cell sensing with greater tolerance of device mismatches.

Abstract: A nonvolatile semiconductor memory device and a writing method thereof are provided. The nonvolatile semiconductor memory device includes a cell array, a controller configured to receive input data from an outside source, an address latch unit configured to store a Y-address of the input data and X-addresses respectively corresponding to at least two wordlines, over which the input data is written, based on an address of the input data output from the controller, and a page buffer configured to receive the input data from the controller and temporarily store the input data. The controller writes the data stored in the page buffer over the two wordlines in the cell array based on the at least two X-addresses and the Y-address.

Abstract: Apparatus and systems for improved PVT invariant fast rank switching in a DDR3 memory subsystem. A clock skew control circuit is provided between a memory controller and a DDR3 SDRAM memory subsystem to adjust skew between the DDR3 clock signal and data related signals (e.g., DQ and/or DQS). A initial write-leveling procedure determines the correct skew and programs a register file in the skew adjustment circuit. The register file includes a register for each of multiple ranks in the DDR3 memory. The values in each register serve to control selection of alignment of the data related signals to align with one of multiple phase shifted versions of a 1× DDR3 clock signal. The phase shifted clock signals are generated by clock divider circuits from a 2× DDR clock signal and use of a single fixed delay line approximating ? of a 1× DDR3 clock period.

Abstract: A ferroelectric semiconductor storage device includes: a block having a plurality of ferroelectric memory cells connected in series, each of the plurality of ferroelectric memory cells including a ferroelectric capacitor and a transistor connected in parallel to both ends of the ferroelectric capacitor; a word line connected to each of the transistors; a selection transistor connected to one end of the block; a bit line connected to the selection transistor; and a plate line connected to the other end of the block. The number of ferroelectric memory cells connected in each block in the ferroelectric semiconductor storage device is odd.

Abstract: A method for operating a static random access memory (SRAM) cell includes providing the SRAM cell having a static read margin and a static write margin, wherein the static read margin is greater than the static write margin; applying a dynamic power to perform a write operation on the SRAM cell; and applying a static power to perform a read operation on the SRAM cell.

Abstract: A semiconductor integrated circuit has a central processing unit and a rewritable nonvolatile memory area disposed in an address space of the central processing unit. The nonvolatile memory area has a first nonvolatile memory area and a second nonvolatile memory area, which memorize information depending on the difference of threshold voltages. The first nonvolatile memory area has the maximum variation width of a threshold voltage for memorizing information set larger than that of the second nonvolatile memory area. When the maximum variation width of the threshold voltage for memorizing information is larger, since stress to a memory cell owing to a rewrite operation of memory information becomes larger, it is inferior in a point of guaranteeing the number of times of rewrite operation; however, since a read current becomes larger, a read speed of memory information can be expedited.

Abstract: Address comparison circuits each compare the defect addresses programmed in the redundancy fuse circuits with an access address and output a redundancy signal when a comparison result is a match. A switch circuit is controlled to switch according to a redundancy selection signal output from a selection fuse circuit, and validates in response to the redundancy signal either a corresponding regular redundancy line or the reservation redundancy line. By dividing the redundancy lines into the regular redundancy lines and the reservation redundancy line, each of the redundancy fuse circuits can be made to correspond to one of the plurality of redundancy lines with the simple switch circuit. Therefore, a difference in propagation delay time of a signal can be made small and a difference in access time can be made small between when relieving a defect and when there is no defect.

Abstract: A semiconductor memory apparatus according to an embodiment of the invention includes a delay enable unit that generates a delay enable signal in response to an external ODT signal and an idle signal, a delay selecting unit that outputs the idle signal or a delay idle signal, which is obtained by delaying the idle signal by a first delay time, in response to the delay enable signal, and a DLL clock control unit that generates a control signal in response to the idle signal or the delay idle signal during a slow power down exit mode.

Abstract: In a memory cell array, a plurality of memory cells which store data in the form of n values (n is a natural number which is not smaller than 2) which are in first and second to nth states are arranged in a matrix form. Before a write operation of storing data in a first memory cell in the memory cell array, when at least one second memory cell which is adjacent to the first memory cell is in the first state and does not reach a first threshold voltage, a control circuit performs a write operation in the second memory cell up to the first threshold voltage.