摘要:
First and second ferroelectric capacitors are selectively connected with a first bit line. Data is read to the first bit line from a first ferroelectric capacitor by applying a first voltage in a coordinate increasing direction of an axis or from the second ferroelectric capacitor by applying a second voltage having a sign opposite to the first voltage in the coordinate increasing direction. Third and fourth ferroelectric capacitors are selectively connected with a second bit line. Data is read to the second bit line from the third ferroelectric capacitor by applying a third voltage having the same sign as the first voltage in the coordinate increasing direction or from the fourth ferroelectric capacitor by applying a fourth voltage having the same sign as the second voltage in the coordinate increasing direction. A sense amplifier amplifies the potential difference between the first and second bit lines.
摘要:
The memory cell array includes a memory cell, the memory cell including a ferroelectric capacitor and a transistor. The memory cell array includes a word line selecting the memory cell, a plate line applying a drive voltage to the ferroelectric capacitor, and a bit line reading data from the ferroelectric capacitor. A selection transistor selectively connects the memory cell to the bit line. A dummy cell provides a reference potential, the reference potential being referred to for a potential read from the memory cell. A sense amplifier circuit includes a plurality of amplification circuits amplifying the potential difference between a bit-line pair. A decoupling circuit electrically cuts off the bit line between the amplification circuits.
摘要:
A semiconductor integrated circuit device includes unit cells, memory cell blocks, bit lines, word lines, block select signal lines, plate lines, and a plate line driver. The unit cell includes a cell transistor and a ferroelectric capacitor connected between a source and a drain of the cell transistor. The memory cell block includes the unit cells connected in series between a first terminal and a second terminal and a block select transistor connected between the second terminal and a third terminal. The bit line connects commonly the third terminals of the blocks. The word line connects commonly gates of cell transistors in the blocks. The block select signal line connects commonly gates of block select transistors in the blocks. The plate line connects commonly the first terminals of the blocks. The plate line driver is connected to the plate lines and applies a potential to the plate lines.
摘要:
A semiconductor memory device includes a memory cell block, gate lines and branch lines. The memory cell block includes memory cells connected in series. Each of memory cells has a cell transistor having a source and a drain and a ferroelectric capacitor inbetween the source and the drain. The gate lines are connected to the gates of the cell transistors of the memory cell block. The gate lines have a predetermined width and are arranged at regular intervals. The branch lines are formed of a layer different from that of the gate lines, arranged parallel to the gate lines, and each connected thereto. The branch lines have a predetermined width and are arranged at regular intervals. The sum of the width of the branch lines and the interval between adjacent branch lines differing from the sum of the width of the gate lines and the interval between adjacent gate lines.
摘要:
A memory cell is formed with a resistance variable element, which is interposed between first and second electrodes and can store resistance changes representing 2 or more different values, and first and second cell transistors having source terminals thereof connected to the first electrode, and gates thereof to a word line. A drain of the first cell transistor is connected to a bit line, and a drain of the second cell transistor is connected to a data line. The second electrode is connected to a source line. During a read operation, the first and second cell transistors are kept in an ON state, and a current is supplied from the bit line to the source line through the memory cell. Data is read according to the electrical potential difference between the data line and the source line.
摘要:
According to one embodiment, a memory system includes a nonvolatile first memory, a nonvolatile second memory, a data-copy processing unit and a data invalidation processing unit. The first memory has a storage capacity for n (n≧2) pages per word line. The nonvolatile second memory temporarily stores user data write-requested from a host apparatus. The data-copy processing unit executes data copy processing including reading out, in page units, the user data stored in the second memory and sequentially writing the read-out user data in page units in the first memory. The data invalidation processing unit selects, after the execution of the data copy processing, based on whether the memory cell group per word line stores user data for n pages, user data requiring backup out of the user data subjected to the data copy processing and leaves the selected user data in the second memory as backup data.
摘要:
According to one embodiment, there is provided a fusion memory including a first memory cell array formed of a NAND cell unit and a second memory cell array formed of a DRAM cell on a semiconductor substrate. The NAND cell unit is formed of a non-volatile memory cell having a two-layer gate structure in which a first gate and a second gate are stacked, and a selective transistor connecting the first and second gates of the non-volatile memory cell. The DRAM cell is formed of a cell transistor having a structure same as the structure of the selective transistor, and a MOS capacitor having a structure same as the structure of the non-volatile memory cell or the selective transistor.
摘要:
This disclosure concerns a memory including: a first memory region including memory groups including a plurality of memory cells, addresses being respectively allocated for the memory groups, the memory groups respectively being units of data erase operations; a second memory region temporarily storing therein data read from the first memory region or temporarily storing therein data to be written to the first memory region; a read counter storing therein a data read count for each memory group; an error-correcting circuit calculating an error bit count of the read data; and a controller performing a refresh operation, in which the read data stored in one of the memory groups is temporarily stored in the second memory region and is written back the read data to the same memory group, when the error bit count exceeds a first threshold or when the data read count exceeds a second threshold.
摘要:
To provide a memory system which determines a memory state such as an exhaustion level and allows a memory to be efficiently used.The memory system includes a NAND type flash memory 1 in which data can be electrically written/erased, a nonvolatile memory 2 which counts the number of erase operations of the NAND type flash memory 1 and retains the number of erase operations and a maximum number of erase operations, and a controller 3 which has a connection interface 31 to be given a self-diagnosis command from a computer 4, and retrieves the number of erase operations and the maximum number of erase operations from the nonvolatile memory 2 based on the self-diagnosis command and outputs the number of erase operations and the maximum number of erase operations to the computer 4 through the connection interface 31.
摘要:
A power supply circuit has a constant voltage circuit, a first MOS transistor, a second MOS transistor, a third MOS transistor, a first voltage dividing circuit that outputs a first divided voltage obtained by dividing the voltage of the output terminal by a first voltage dividing ratio, and a first differential amplifier circuit which is fed with a reference voltage and the first divided voltage and has an output connected to a gate of the second MOS transistor. The first differential amplifier circuit outputs a signal to turn on the second MOS transistor when the first divided voltage is higher than the reference voltage, and the first differential amplifier circuit outputs a signal to turn off the second MOS transistor when the first divided voltage is lower than the reference voltage.