296 results about "Write bit" patented technology

An SRAM memory cell that has a relatively small power consumption when writing a write value of ‘0’ to the memory cell includes cross-coupled first and second inverters, at least one read access transistor for selectively coupling a respective read bit line to a common connection node of a respective one of the first and second inverters, a switching transistor for selectively coupling the second inverter to a ground terminal, and a write access transistor for selectively coupling the common connection node of the second inverter to a write bit line.

A write bit line and a read bit line are provided separately for a memory cell. A source line connecting to the memory cell is formed of a source impurity region the same in conductivity type as a substrate region. A memory cell transistor and the source impurity region are connected by a metal interconnection line of a low resistance. A rise in the source line potential can be prevented, and a memory cell current can reliably be generated according to storage data. Further, fast data reading can be achieved. Additionally, by performing precharging and data amplification in a unit of read bit line, the load of the read bit line can be alleviated to achieve fast reading. An accessing time of a non-volatile semiconductor memory device that uses a variable resistance element as a storage element is reduced without increasing the current consumption.

A multi-port memory cell includes a first SRAM element having a first pair of access transistors electrically coupled to a pair of FIFO write bit lines. A second dual-port SRAM element is also provided. This second dual-port SRAM element has a second pair of access transistors electrically coupled to a pair of FIFO read bit lines and a third pair of access transistors electrically coupled to a pair of memory read bit lines. A direct path data transfer circuit is provided. This transfer circuit is configured to support a unidirectional data transfer path that extends from first storage nodes within the first SRAM element to second storage nodes within the second dual-port SRAM element. This transfer circuit is also responsive to a direct path word line signal.

A semiconductor device which stores data by using a transistor whose leakage current between source and drain in an off state is small as a writing transistor. In a matrix including a plurality of memory cells in which a drain of the writing transistor is connected to a gate of a reading transistor and the drain of the writing transistor is connected to one electrode of a capacitor, a gate of the writing transistor is connected to a writing word line; a source of the writing transistor is connected to a writing bit line; and a source and a drain of the reading transistor are connected to a reading bit line and a bias line. In order to reduce the number of wirings, the writing bit line or the bias line is substituted for the reading bit line in another column.

A memory cell for use in a memory array includes a storage element for storing a logical state of the memory cell, a write circuit and a read circuit. The write circuit is operative to selectively connect a first node of the storage element to at least a first write bit line in the memory array in response to a write signal for selectively writing the logical state of the memory cell. The read circuit includes a substantially high impedance input node connected to the storage element and an output node connectable to a read bit line of the memory array. The read circuit is configured to generate an output signal at the output node which is representative of the logical state of the storage element in response to a read signal applied to the read circuit. The memory cell is configured such that the write circuit is disabled during a read operation of the memory cell so as to substantially isolate the storage element from the first write bit line during the read operation. A strength of at least one transistor device in the storage element is separately optimized relative to a strength of at least one transistor device in the write circuit and / or the read circuit.

MRAM has read word lines WLR and write word line WLW extending in the y direction, write / read bit line BLW / R and write bit line BLW extending in the x direction, and the memory cells MC disposed at the points of the intersection of these lines. The memory MC includes sub-cells SC1 and SC2. The sub-cell SC1 includes magneto resistive elements MTJ1 and MTJ2 and a selection transistor Tr1, and the sub-cell SC2 includes magneto resistive elements MTJ3 and MTJ4 and a selection transistor Tr2. The magneto resistive elements MTJ1 and MTJ2 are connected in parallel, and the magneto resistive elements MTJ3 and MTJ4 are also connected in parallel. Further, the sub-cells SC1 and SC2 are connected in series between the write / read bit line BLW / R and the ground.

A semiconductor memory device includes memory cells, write bit lines, read bit lines, latch circuits, a n-channel MOS transistor, and voltage setting circuits. The memory cell includes a first MOS transistor having a charge accumulation layer and a control gate. The first MOS transistors are connected commonly to the write bit lines and read bit lines. The latch circuits are provided for the write bit lines and hold write data for the memory cells. The n-channel MOS transistor transfer “1” data to the latch circuits in a data latch operation. The voltage setting circuits supply a potential corresponding to “0” data to the write bit lines in a read operation. In a data latch operation, the latch circuit corresponding to the write bit line connected to the memory cell into which “0” data is to be written latches the potential supplied to the write bit lines in a read operation.

A dual port static random access memory (SRAM) having dedicated read and write ports provides high speed read operation with reduced leakages. The dual port SRAM includes at least one write word line, at least one read word line, at least one pair of write bit line and read bit line, a plurality of rows and columns. Each rows and column has at least one cell which includes at least one pair of memory elements cross-coupled to form a latch for storing data, a pair of write access semiconductors and a pair of read access semiconductors. The SRAM includes an inverter circuit and a pull down circuit which are operatively coupled to the at least one cell to increase read operation performance and eliminate leakage.

A magnetic random access memory with write and read circuits using magnetic tunnel junction (MTJ) devices wherein MTJs are arranged at cross points of word lines and read bit lines to form memory cells. After write bit lines and read bit lines are arranged parallel to each other, current bypass paths are formed allowing current to bypass the side and bottom of the MTJ. Thus, an electric field having intensity enough to change the magnetization direction of the MTJ, is applied only to each selected cell. In a write operation, the magnetization direction of a free layer in the MTJ is formed to be parallel or antiparallel to the magnetization direction of a pinned ferromagnetic layer by the current passing through the word line and the current bypass path.

First and second current drivers are connected to one end of corresponding first and second write bit lines, respectively, and the first and second write bit lines are directly connected, at the other end, to a common line. The first and second current drivers receive a first power supply voltage and the ground voltage, while the common line receives a second power supply voltage higher than the ground voltage and lower than the first power supply voltage. The first and second current drivers cause a current for data writing to flow in a first direction based on a voltage difference between the first power supply voltage and the second power supply voltage, and cause a current for data writing to flow in a second direction based on a voltage difference between the second power supply voltage and the ground voltage.

Blocks are connected to a read bit line. One block has MTJ elements which are connected to each other in series between the read bit line and a ground terminal. A MTJ elements are superposed on, e.g., a semiconductor substrate. A read bit line is arranged on the superposed MTJ elements. A write word line extending in a X-direction and a write bit line extending in a Y-direction are arranged in the vicinity of the MTJ elements in the block.