摘要:
A semiconductor memory device includes a memory cell array, row decoder, bit line pairs, sense amplifier, sense amplifier control circuit, data latch, transfer gate, transfer gate control circuit, and write circuit. The memory cell array has dynamic memory cells arranged in an array form. The row decoder decodes a row address signal to select a desired one of rows of the memory cell array. Each of the bit line pairs is connected to those of the memory cells which are arranged on a corresponding one of columns of the memory cell array. The sense amplifier amplifies data read out on the paired bit lines and positively feeding data back to the paired bit lines to hold the data. The sense amplifier control circuit controls the operation of the sense amplifier. The data latch latches readout data and write data. The transfer gate transfers data between the data latch and the sense amplifier. The transfer gate control circuit controls the transfer gate. The write circuit writes data into the data latch in synchronism with a clock signal. At the time of writing data into the memory cells, data is previously supplied to the data latch by the write circuit and latched in the data latch, and after the transfer gate control circuit controls the transfer gate to supply data to the bit line pairs from the data latch, the sense amplifier control circuit activates the sense amplifier.
摘要:
A semiconductor device of a memory-macro type can be designed within a short time to have a desired storage capacity, which does not occupy a large area, so as to reduce the chip cost. The semiconductor device includes a memory macro having sub-memory macros, each sub-memory macro having a DRAM memory-cell array, and a row decoder and a column decoder for selecting any desired memory-cell from the memory cell of the array. The memory macro also includes a control-section macro having a DC potential generating circuit for generating various DC potentials required to drive the sub-memory macros. At least one of the sub-memory macros is combined with the control-section macro to form the memory macro as a one-chip memory capable of storing an integral multiple of N bits.
摘要:
A data register that stores the data corresponding to the selected memory cell in a memory cell array is provided near the memory cell array. A decoder that selects the data from the data register starts decoding in response to an address signal accessing the memory cells in synchronization with a clock signal determining the operation period. In the first half of an operation period of the clock signal, the decoder outputs a signal in response to a signal corresponding to the address signal determined in the preceding operation period. According to the output of the decoder, the data register is selected. In the latter half of the operation period, a signal corresponding to a new address signal for the next operation period is transferred to the decoder. By doing this, the output control signal in the decoder is caused to synchronize with a signal driving an address signal, enabling the proper address to be selected without fail.
摘要:
A semiconductor memory device comprises column decoders of the number greater than the number of column addresses of a memory cell array and logical circuits of the same number as that of the column addresses. A column gate of a column is controlled by means of a logical OR between outputs from a plurality of column decoders for decoding different column addresses. As a result, even a column located at an end of the memory cell array can be accessed by means of a logical OR between outputs from a column decoder corresponding to the column and another column decoder.
摘要:
When data stored in a memory cell of a memory cell array is written into cache memory, a write signal LW is set at an "H" level. The write signal LW is input into a data-line pair initialization select circuit via an initialization control circuit, and a signal EQE is set at an "H" level in all columns. A data-line pair initialization circuit then sets the potential of the data-line pairs in all columns at the same level. When the write signal LW is input to a transfer gate via a transfer gate control circuit, the transfer gates in all columns are turned ON. The delay time of the transfer gate control circuit is the same as or greater than the delay time of the initialization control.
摘要:
According to the present invention, a data bus common to a plurality of memory cell arrays is formed by selecting a column so as to prevent a data collision from occurring. Specifically, two memory cell arrays have each of data buses in common. A column decoder is supplied with a control signal to control a column selection logic circuit. The column selection logic circuit is so controlled that the data read out to the data buses in response to the control signal is prevented from colliding with each other during the simultaneous access to the two cell arrays.
摘要:
A semiconductor memory device includes a memory cell array, row decoder, bit line pairs, sense amplifier, sense amplifier control circuit, data latch, transfer gate, transfer gate control circuit, and write circuit. The memory cell array has dynamic memory cells arranged in an array form. The row decoder decodes a row address signal to select a desired one of rows of the memory cell array. Each of the bit line pairs is connected to those of the memory cells which are arranged on a corresponding one of columns of the memory cell array. The sense amplifier amplifies data read out on the paired bit lines and positively feeding data back to the paired bit lines to hold the data. The sense amplifier control circuit controls the operation of the sense amplifier. The data latch latches readout data and write data. The transfer gate transfers data between the data latch and the sense amplifier. The transfer gate control circuit controls the transfer gate. The write circuit writes data into the data latch in synchronism with a clock signal. At the time of writing data into the memory cells, data is previously supplied to the data latch by the write circuit and latched in the data latch, and after the transfer gate control circuit controls the transfer gate to supply data to the bit line pairs from the data latch, the sense amplifier control circuit activates the sense amplifier.
摘要:
A semiconductor memory device includes a sense amplifier which senses data read out from a memory cell, a transfer gate coupled to an output of the sense amplifier, and a data latch circuit coupled to the transfer gate. The data latch circuit includes two MOS transistors of a same conductivity type connected in series between a pair of I/O data lines. The gates of the two MOS transistors are cross-coupled to the data lines respectively, thereby enabling a rapid data transfer between the memory cell and a data bus.
摘要:
Even-numbered columns are arranged in the first memory cell array (bank), and odd-numbered columns are arranged in the second memory cell array (bank). A column address signal is input to an adder through a buffer. When data is read out of two or more columns, the adder generates a column address signal whose address value is more than that of the column address signal by one. The adder supplies a first column decoder with a column address signal for addressing an even-numbered column and supplies a second column decoder with a column address signal for addressing an odd-numbered column. Since the even-numbered columns and odd-numbered columns are arranged in their separate memory cell arrays, data read out of continuous two or more columns do not collide with each other.
摘要:
On a semiconductor substrate, there are formed a first macro cell having wiring layers of three layers each formed of a metal wiring layer (for example, an aluminum wiring) and a second macro cell having wiring layers of three layers each formed of a metal wiring layer similar to the first macro cell. The first macro cell is formed to have a wiring structure of three wiring layers though the originally necessary number of metal wiring layers is two. The metal wiring layer of each layer on the first macro cell is formed of the same material as the metal wiring layer of the corresponding each layer on the second macro cell. Moreover, the metal wiring layer of each layer is formed to have the same film thickness. In order to connect the first and second macro cells to each other, a macro interconnection wiring is formed to be included in the third wiring layer (uppermost wiring layer).