摘要:
In a semiconductor memory device, a memory cell is connected with a local sense amplifier and a global sense amplifier via a local bit line and a global bit line. The local sense amplifier is a single-ended sense amplifier including a single MOS transistor, which detects a potential of the local bit line which varies when reading and writing data with the memory cell. The threshold voltage of the MOS transistor is monitored so as to produce a high-level write voltage and a low-level write voltage, which are corrected and shifted based on the monitoring result so as to properly perform a reload operation on the memory cell by the global local sense amplifier. Thus, it is possible to cancel out temperature-dependent variations of the threshold voltage and shifting of the threshold voltage due to dispersions of manufacturing processes.
摘要:
A semiconductor memory device (e.g. DRAM) is constituted of a memory cell array including a plurality of memory cells, a plurality of word line drivers, a plurality of sense amplifiers, and a plurality of dummy capacitors. The memory cells, each of which includes a transistor and a capacitor, are positioned at intersections between the word lines and the bit lines. The first electrodes of the capacitors are connected to the transistors in the memory cells. The first electrodes of the dummy capacitors are connected together and are supplied with a second potential (e.g. VDD or VSS). The second electrodes of the dummy capacitors are connected together with the second electrodes of the capacitors of the memory cells and are supplied with a first potential (e.g. VPL). The dummy capacitors serve as smoothing capacitances for the plate voltage VPL so as to reduce plate noise.
摘要:
A semiconductor memory device (e.g. DRAM) is constituted of a memory cell array including a plurality of memory cells, a plurality of word line drivers, a plurality of sense amplifiers, and a plurality of dummy capacitors. The memory cells, each of which includes a transistor and a capacitor, are positioned at intersections between the word lines and the bit lines. The first electrodes of the capacitors are connected to the transistors in the memory cells. The first electrodes of the dummy capacitors are connected together and are supplied with a second potential (e.g. VDD or VSS). The second electrodes of the dummy capacitors are connected together with the second electrodes of the capacitors of the memory cells and are supplied with a first potential (e.g. VPL). The dummy capacitors serve as smoothing capacitances for the plate voltage VPL so as to reduce plate noise.
摘要:
A dynamic RAM incorporates a plurality of dynamic memory cells, each of which comprises a MOSFET having a gate set as a select terminal, one source and drain set as input/output terminals, and the other source and drain connected to storage nodes of the capacitor and a capacitor, a plurality of word lines respectively connected to the select terminals of the plurality of dynamic memory cells, a plurality of complementary bit line pairs respectively connected to the input/output terminals of the plurality of dynamic memory cells, and a sense amplifier array comprising a plurality of latch circuits which respectively amplify differences in voltage between the complementary bit line pairs placed so as to extend in directions opposite to each other from each pair of input/output terminals. Power supply lines are provided in mesh form inclusive of a portion above word drivers.
摘要:
A semiconductor memory device is provided which can achieve the high integration, ultra-high speed operation, and significant reduction of power consumption during the information holding time, by reducing the increase in the area of a memory cell and obtaining a period of the ultra-high speed readout time and ensuring a long refresh period at the time of the self refresh. A DRAM employing a one-intersection cell·two cells/bit method has a twin cell structure employing a one-intersection 6F2 cell, the structure in which: memory cells are arranged at positions corresponding to all of the intersections between a bit-line pair and a word line; and when a half pitch of the word line is defined as F, a pitch of each bit line of the bit-line pair is larger than 2F and smaller than 4F. Further, an active region in the silicon substrate, on which a source, channel and drain of the transistor of each memory cell are formed, is obliquely formed relative to the direction of the bit-line pair.
摘要:
A dynamic RAM comprising a plurality of word lines respectively connected to address select terminals of a plurality of dynamic memory cells, a plurality of complementary bit line pairs respectively connected to input/output terminals of the plurality of dynamic memory cells and placed in directions opposite to one another, and a sense amplifier array which is supplied with an operating voltage according to an operation timing signal and comprises a plurality of latch circuits for respectively amplifying the differences in voltage between the complementary bit line pairs. In the dynamic RAM, common electrodes provided in opposing relationship to storage nodes corresponding to connecting points between address select MOSFETs and information storage capacitors of the plurality of dynamic memory cells, on both sides with the sense amplifier array as the center are connected to one another while circuit connections in the sense amplifier array are being ensured by wiring using the common electrodes.
摘要:
The contact resistance of each switch is reduced, and the on-resistances of all of the switches are set to be uniform, while the area required for arrangement of bit line selection switches is not increased.The switches are connected to one-side ends of the bit lines provided at the odd-numbered positions, and are connected to the other-side ends of the bit lines provided at the even-numbered positions. A pair of odd-numbered or even-numbered bit lines are connected to the terminals of each sense amplifier, respectively. The memory cells are arranged at predetermined intersection points of the word lies and the bit lines, the number of the predetermined intersection points being equal to half of all the intersection points thereof, in such a manner that when one word line is selected, the memory cells connected to the selected word-line can be electrically connected in such a manner that one memory cell is electrically connected to each terminal of the unit circuits.
摘要:
A semiconductor device includes a first region having first bit lines, first word lines and first memory cells; a second region having second bit lines, second word lines and second memory cells; a third region having sense amplifiers placed between the first region and the second region; a first conductive layer being over the first region; a second conductive layer being over the second region; and a connecting layer, being over the third region, which electrically connects the first conductive layer with the second conductive layer. The sense amplifiers amplify differences in voltage between the first bit lines and the second bit lines. Each of the first memory cells includes a first storage capacitor having an electrode connected to the first conductive layer. Each of the second memory cells includes a second storage capacitor having an electrode connected to the second conductive layer.
摘要:
When a phase shift method is used as lithography where sense amplifiers are alternately placed in a one intersecting-point memory capable of implementing a reduction in the area of a DRAM, it was difficult to layout data lines in a boundary region between sense amplifiers and each memory array. Therefore, there is provided a semiconductor device according to the present invention. In the semiconductor device, two data lines continuous within the sub memory arrays or interposed therebetween are connected to the adjacent sense amplifiers as a system for drawing data lines from sub memory arrays (SMA) to sense amplifiers (SA) when the sense amplifiers are alternately placed. Namely, the number of data lines interposed between data lines respectively connected to two adjacent sense amplifiers is set to even numbers (0, 2, 4, . . . ). Owing to the above configuration, a break and a short circuit in a portion where a sense amplifier block and a sub memory array are connected, can be avoided, and a connection layout is facilitated.
摘要:
A direct sense amplifier of the present invention incorporates and isolates: an MOS transistor serving as a differential pair and having a gate connected to a bit line; and an MOS transistor controlled by a column select line wired between RLIO lines in a bit-line direction, and further connects a source of the MOS transistor serving as the differential pair to a common source line wired in the word-line direction. Since the direct sense amplifier only in a select map is activated by the column select line and the common source line during an read operation, power consumption is significantly reduced during the read operation. Also, since a parasitic capacitance of the MOS transistor serving as the differential pair is separated from the local IO line, a load capacity of the local IO line is reduced and the read operation is speeded up. In addition, during the read operation, a data pattern dependency of the load capacity of the local IO line is reduced and a post-manufacture test is easily made.