Abstract: In a memory cell contained in a memory circuit portion of a system LSI, a gate electrode of an N-channel MOS transistor and a cell plate electrode of a capacitor are formed by the same interconnection layer. Thus, the system LSI can be produced using the CMOS logic process alone so that the system LSI including the memory circuit portion having a relatively large capacity can be produced at a low cost.

Abstract: When a row active command ACT_CMD is externally input, an internal clock control circuit activates a signal int.CKE, so that an external clock signal ext.CLK is responsively supplied to an internal memory array as signal int.CLK. Thus, clock control is meticulously conducted, whereby a system LSI with reduced current consumption in the memory array can be realized.

Abstract: A self refresh timer is set constantly to an operation state to render a refresh request signal FAY active periodically. When contention occurs between the refresh request signal FAY and an externally applied read or write command, a row selection related circuit/command generation related circuit controls a row related control signal so that a refresh operation is carried out after, for example, the read or write operation ends. A submemory array SMA is divided more small than that of the conventional case, and the refresh cycle ends in a shorter period of time. Therefore, a read operation and a refresh operation can be completed within a read cycle time. A DRAM core that can be employed with control as simple as that of an SRAM can be realized.

Abstract: Drains of first and second transistors are connected to a low level line of an internal circuitry such as a sense amplifier related to determination of a potential in a memory cell. The first transistor has its gate diode-connected to a sense drive line and its source grounded. The second transistor receives at its gate an internally generated signal, and its source is grounded. In the standby state, the potential of the sense drive line is set higher than low level of said word lines by the threshold voltage Vthn of the first transistor and used as dummy GND potential Vss′, and in the active state, the second transistor is rendered conductive so as to prevent floating of the sense drive line from the dummy GND potential Vss′.

Abstract: There is provided a semiconductor integrated circuit device comprising: a field placement creating a field pattern in an array form by closest packing on a first conductance-type semiconductor substrate, the field pattern including a plurality of memory cells which define an active area and a device isolation region of a field effect transistor, and which are arranged in a predetermined pitch in the longitudinal and transverse directions, respectively, each memory cell having a pattern of a certain length-to-width size; a cell plate placement providing a capacitor structure between a second conductance-type diffusion region formed by an impurity implant to the active area and a cell plate electrode formed so as to cover part of the active area with a predetermined cell plate pattern through a capacitor dielectric, the cell plate pattern extending in the transverse direction with a certain length size; and a word line placement in which a word line pattern is arranged in the transverse direction of a vacant zo

Abstract: A first test clock signal and a second test clock signal are generated from a common basic test clock signal using a delay line with a changeable delay time and a delay stage with a fixed delay time. A memory circuit is operated in synchronization with one of the first and second test clock signals, and the memory circuit is provided with a signal/data according to the other test clock signal. Thus, the set-up time and the hold time of a signal for the memory can be measured with accuracy in a memory-merged system LSI.

Abstract: A sense operation by a sense amplifier circuit is carried out by selecting a pair of subword lines simultaneously and coupling each bit line in a pair to a memory cell. Since complementary data are stored into these two memory cells, the voltage between the bit lines in a pair in a sense operation can be set large enough to allow increase of the refresh interval. Therefore, power consumption in a data retaining mode can be reduced.

Abstract: A DRAM includes a semiconductor substrate and unit blocks. Each unit block includes a peripheral circuit and eight memory blocks arranged to surround the peripheral circuit. Each memory block includes a plurality of word lines, a plurality of bit lines, a plurality of memory cells, a row decoder, and a column decoder.

Abstract: In a data holding mode, data storage in a one bit/one cell scheme in a normal operating mode are rearranged into data storage in a twin-cell mode in which data are stored in a one bit/two cell scheme. In the twin-cell mode, two sub word lines are simultaneously driven into a selected state, and storage data of memory cells are read out on both of bit lines in a pair, to perform a sense operation. Thus, the read-out voltage can be increased to improve the data retention characteristics for lengthening a refresh interval, resulting in a reduced power consumption in the data holding mode.

Abstract: The inventive semiconductor memory device comprises an interface area transmitting/receiving data to/from an external device, an address-system circuit receiving an address signal from the interface area, a memory cell array (subarray), a preamplifier/write driver for writing data received from the interface area in the subarray or outputting data read from the subarray to the interface area, and an internal data bus transmitting write data and read data. The address-system circuit and the preamplifier/write driver are arranged between the interface area and the memory cell array. The internal data bus is arranged in a row direction. The length of a wire connecting each circuit with the interface area can be minimized, and a high data transfer rate is implemented.

Abstract: Read data line pairs, write data line pairs, a spare read data line pair, and a spare write data line pair are provided extending in the column direction over a memory cell array. Spare bit repair is performed by replacing a data line pair. Column redundancy control circuit changes the timing for outputting the result of spare determination for a data write mode and for a data read mode. A semiconductor memory device suitable for merging with a logic and capable of reducing the current consumption and achieving a higher operation frequency is provided.

Abstract: A semiconductor integrated circuit in which a logic and a memory are merged, includes a voltage generation unit for generating two or more internal power supply voltages based on two or more external power supply voltages supplied from outside the voltage generation unit with different timings and for furnishing the plurality of internal power supply voltages to the memory. The voltage generation unit includes a standby unit with a small current-feed ability that is always activated, for generating the plurality of internal power supply voltages, and an active unit with a large current-feed ability that is activated as needed, for generating the plurality of internal power supply voltages. An activation control unit prevents the active unit from being activated until all of the plurality of external power supply voltages rise.

Abstract: In a word line drive circuit for driving a word line to a boosted voltage level, a drive signal that is activated in response to a wafer burn-in signal is applied to the gate of a transistor for preventing the floating state of the word line. Even if a boost signal is transmitted to a corresponding word line through a word line driver circuit, the floating state prevention transistor can be turned off at high speed, an electric charge flow path can be cut off, and the word line can be driven reliably to the boosted voltage level. Therefore, reliable burn-in can be implemented.

Abstract: Drains of first and second transistors are connected to a low level line of an internal circuitry such as a sense amplifier related to determination of a potential in a memory cell. The first transistor has its gate diode-connected to a sense drive line and its source grounded. The second transistor receives at its gate an internally generated signal, and its source is grounded. In the standby state, the potential of the sense drive line is set higher than low level of said word lines by the threshold voltage Vthn of the first transistor and used as dummy GND potential Vss′, and in the active state, the second transistor is rendered conductive so as to prevent floating of the sense drive line from the dummy GND potential Vss′.

Abstract: In a test interface circuit arranged between an embedded memory and a test data input/output (I/O) terminal, a first-in first-out circuit for successively storing test data is arranged for controlling a latency of data read from the embedded memory. The test interface circuit for the embedded memory can reduce the number of test data I/O terminals, and can increase the executable test patterns.

Abstract: On transistors P1, P2, N1 and N2 constituting an NAND gate, a interconnection pattern W of metal having high melting point and aluminum interconnection patterns Al1 and Al2 are stacked. A local line LL for connecting transistors P1, P2, N1 and N2 to each other is formed by the interconnection pattern W of metal having high melting point, signal lines SL and SL′ for signal input/output between the NAND gate and the outside are formed by aluminum interconnection pattern Al1, and power supply lines VL and VL′ for applying power supply potentials Vcc and Vss to the NAND gate are formed by the aluminum interconnection pattern Al2. As compared with the prior art in which the local line LL is formed by the aluminum interconnection pattern Al1, the degree of freedom in layout can be improved and the layout area can be reduced.

Abstract: A test interface circuit carries out an operational test based on a signal input to test pin terminals by directly accessing a DRAM core. A frequency multiplication circuit generates an internal test clock signal by multiplying the frequency of an external test clock signal input to the test pin terminal. A data shifter shifts read data from the DRAM core which operates according to the internal test clock signal in a test mode by N clock cycles (N is an integer of at least 0 determined by column latency) of the internal test clock signal to output the read data from the test pin terminals in synchronization with the external clock test signal.

Abstract: A dummy bit line is formed from the same layer as and separately from a bit line, and is running in parallel with the bit line. Capacitor is formed on the layer upper than bit line and has a cell plate. An intermediate interconnection is formed on the layer upper than capacitor and is electrically connected to cell plate and dummy bit line. Thus, a semiconductor memory device is obtained in which a cell plate voltage can reliably be fed to a cell plate while preventing the increase of the area of a chip.

Abstract: A variable impedance power supply line and a variable impedance ground line supplying voltages VCL1 and VSL1, respectively, are set to a low impedance state in a stand-by cycle and in a row related signal set period, and to a high impedance state in a column circuitry valid time period. Variable impedance power supply line and variable impedance ground line supplying voltages VCL2 and VSL2, respectively, are set to a high impedance state in the stand-by cycle, and low impedance state in the active cycle and in the row related signal reset time period. Inverters operate as operating power supply voltage of voltages VCL1 and VSL2 or voltages VCL2 and VSL1, in accordance with a logic level of an output signal in the stand-by cycle and in the active cycle. Thus a semiconductor memory device is provided in which subthreshold current in the stand-by cycle and active DC current in the active cycle can be reduced.

Abstract: A high melting point metal wiring layer, a second aluminum wiring layer, and a third aluminum wiring layer are stacked on transistors forming an inverter train of a hierarchical power supply structure respectively. The high melting point metal wiring layer is employed as a local wire for connecting the transistors with each other, the second aluminum wiring layer is employed as a local bus wire and a hierarchical power supply wire, and the third aluminum wiring layer is employed as a main bus wire and a power supply wire to intersect with the respective wires. Consequently, the wiring layers are easy to lay out, while no main bus region is required dissimilarly to the prior art and it is possible to reduce the layout area.