Abstract: In order to change the precharging voltage level when the bit lines are in the floating state, current control circuits are provided for restricting a current supply amount to the bit lines in the standby state, for example. Data, of which the logic level is fixed, are read out, in the existence of a leak current, due to a change of the bit line voltage caused by this leak current and thereby, the existence of a minute leak current can be detected. Consequently, a semiconductor memory device with an extremely low standby current is implemented by precisely detecting a minute leak current of the bit lines and by repairing the leak current defect.

Abstract: In order to change the precharging voltage level when the bit lines are in the floating state, current control circuits are provided for restricting a current supply amount to the bit lines in the standby state, for example. Data, of which the logic level is fixed, are read out, in the existence of a leak current, due to a change of the bit line voltage caused by this leak current and thereby, the existence of a minute leak current can be detected. Consequently, a semiconductor memory device with an extremely low standby current is implemented by precisely detecting a minute leak current of the bit lines and by repairing the leak current defect.

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: 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 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 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 semiconductor memory device according to the present invention includes a memory core portion, a test mode control circuit for transmitting data output from the memory core portion to an internal node, and a data input/output control circuit for inputting/outputting in series a plurality of pieces of parallel data input/output to each internal node to a data node. The test mode control circuit transmits read data from the memory core portion as it is to the internal node in a normal reading operation, and compresses data output from the memory core portion on the basis of a prescribed unit and transmits the data to the internal node in a test mode. Therefore, the test data compressed for each prescribed unit can be input/output by using a smaller number of data nodes in the test mode than in the normal operation mode.

Abstract: A semiconductor memory device according to the present invention includes a memory core portion, a test mode control circuit for transmitting data output from the memory core portion to an internal node, and a data input/output control circuit for inputting/outputting in series a plurality of pieces of parallel data input/output to each internal node to a data node. The test mode control circuit transmits read data from the memory core portion as it is to the internal node in a normal reading operation, and compresses data output from the memory core portion on the basis of a prescribed unit and transmits the data to the internal node in a test mode. Therefore, the test data compressed for each prescribed unit can be input/output by using a smaller number of data nodes in the test mode than in the normal operation mode.

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: 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: 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: 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 semiconductor circuit or a MOS-DRAM wherein converting means is provided that converts substrate potential or body bias potential between two values for MOS-FETs in a logic circuit, memory cells, and operating circuit of the MOS-DRAM, thereby raising the threshold voltage of the MOS-FETs when in the standby state and lowering it when in active state. The converting means includes a level shift circuit and a switch circuit. The substrate potential or body bias potential is controlled only of the MOS-FETs which are nonconducting in the standby state; this configuration achieves a reduction in power consumption associated with the potential switching. Furthermore, in a structure where MOS-FETs of the same conductivity type are formed adjacent to each other, MOS-FETs of SOI structure are preferable for better results.

Abstract: Current is reduced in driving a word line in stress acceleration testing such as burn-in, and the time required for the stress acceleration testing is reduced. For an address signal applied from an address buffer, a predetermined internal address signal bit is degenerated and a remaining address signal bit is rendered valid in response to an activation of a stress acceleration mode designation signal to simultaneously drive a desired number of word lines of all word lines to selected state. Any number of word lines can be simultaneously selected and hence current flowing in driving word lines can be reduced in the stress acceleration mode. In the stress acceleration mode of operation, bit line voltage and cell plate voltage are changed, and a current required for driving a plurality of word lines into a selected state is limited.

Abstract: A semiconductor circuit device having a triple-well structure wherein a predetermined potential level is supplied to a top well without a contact region formed in the top well is disclosed. In an N-type ion implantation step for forming an N-type well region (1) in a P-type semiconductor substrate (5), a mask of a predetermined configuration is used so that ions are not implanted into a region of a portion which is to serve as a bottom portion (1B) of the well region (1). Then, the N-type well region (1) is formed which is shaped such that a portion (6) having P-type properties remains partially in the bottom portion (1B). The P-type portion (6) establishes electrical connection between a P-type well region (2) and the semiconductor substrate (5) to permit the potential applied to a contact region (4) to be supplied to the well region (2) therethrough. The portion (6) may include a plurality of portions (6) which allow uniform potential supply.

Abstract: A first transistor having a central impurity region connected to a power supply node and outer-side impurity regions connected to an output node and a second transistor having a central impurity region connected to the output node and outer-side impurity regions connected to the power supply node are so arranged that the impurity regions connected to the power supply node are adjacent to or faced to those connected to the output node. The layout area of an output circuit is reduced without reducing electrostatic damage resistance by parasitic field transistors.

Abstract: On a surface of a semiconductor chip having a longer side and a shorter side, a line of a plurality of first pads and a line of a plurality of second pads are arranged in the shape of a cross. Upon multibit expansion, increase in length of the longer side of semiconductor chip can be suppressed even though the number of pads is increased by additionally providing the second pad. In addition, there is no need to reduce the pitch between pads. Thus, a semiconductor memory device allowing multibit expansion is provided without an increase in size of the chip and the pad or reduction in pitches between pads and between pins.

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: The level shifter circuit of an internal down converter includes a P channel MOS transistor constituting a resistance component, and a resistor constituting a resistance component. The temperature coefficient of resistance component is set larger than the temperature coefficient of resistance component so that the output voltage of level shifter circuit has a negative temperature characteristic. If a reference voltage generated by reference voltage generation circuit decreases when operating at a high temperature, the output voltage of level shifter circuit decreases as well. Thus, change in an internal voltage due to change in the operation temperature can be compensated.

Abstract: A semiconductor memory device comprises two memory cell arrays (1a, 1b) in which a block divisional operation is performed. Two spare rows (2a, 2b) are provided corresponding to the two memory cell arrays (1a, 1b). Spare row decoders (5a, 5b) are provided for selecting the spare rows (2a, 2b), respectively. One spare row decoder selecting signal generation circuit (18) used in common by the spare row decoders (5a, 5b) is provided. The spare row decoder selecting signal generation circuit (18) can be previously set so as to generate a spare row decoder selecting signal (SRE) when a defective row exists in either of the memory cell arrays (1a, 1b) and the defective row is selected by row decoder groups (4a, 4b). Each of the spare row decoders (5a, 5b) is activated in response to the spare row decoder selecting signal (SRE) and a block control signal.