Abstract: A semiconductor device includes: two level shift circuits having substantially the same circuit configuration; an input circuit that supplies complementary input signals to the level shift circuits, respectively; and an output circuit that converts complementary output signals output from the level shift circuits into in-phase signals and then short-circuits the in-phase signals. According to the present invention, the two level shift circuits having substantially the same circuit configuration are used, and the complementary output signals output from the level shift circuits are converted into in-phase signals before short-circuited. This avoids almost any occurrence of a through current due to a difference in operating speed between the level shift circuits.

Abstract: A semiconductor device includes: two level shift circuits having substantially the same circuit configuration; an input circuit that supplies complementary input signals to the level shift circuits, respectively; and an output circuit that converts complementary output signals output from the level shift circuits into in-phase signals and then short-circuits the in-phase signals. According to the present invention, the two level shift circuits having substantially the same circuit configuration are used, and the complementary output signals output from the level shift circuits are converted into in-phase signals before short-circuited. This avoids almost any occurrence of a through current due to a difference in operating speed between the level shift circuits.

Abstract: A semiconductor device includes a first driver circuit for supplying a first potential to a first power supply node of the sense amplifier, second and third driver circuits for supplying a second potential and a third potential to a second power supply node of the sense amplifier, and a timing control circuit for controlling operations of the first to third driver circuits. The timing control circuit includes a delay circuit for deciding an ON period of the third driver circuit. The delay circuit includes a first delay circuit having a delay amount that depends on an external power supply potential and a second delay circuit having a delay amount that does not depend on the external power supply potential, and the ON period of the third driver circuit is decided based on a sum of the delay amounts of the first and second delay circuits.

Abstract: A semiconductor device includes a first driver circuit for supplying a first potential to a first power supply node of the sense amplifier, second and third driver circuits for supplying a second potential and a third potential to a second power supply node of the sense amplifier, and a timing control circuit for controlling operations of the first to third driver circuits. The timing control circuit includes a delay circuit for deciding an ON period of the third driver circuit. The delay circuit includes a first delay circuit having a delay amount that depends on an external power supply potential and a second delay circuit having a delay amount that does not depend on the external power supply potential, and the ON period of the third driver circuit is decided based on a sum of the delay amounts of the first and second delay circuits.

Abstract: A semiconductor device includes: two level shift circuits having substantially the same circuit configuration; an input circuit that supplies complementary input signals to the level shift circuits, respectively; and an output circuit that converts complementary output signals output from the level shift circuits into in-phase signals and then short-circuits the in-phase signals. According to the present invention, the two level shift circuits having substantially the same circuit configuration are used, and the complementary output signals output from the level shift circuits are converted into in-phase signals before short-circuited. This avoids almost any occurrence of a through current due to a difference in operating speed between the level shift circuits.

Abstract: To provide a semiconductor device including: first and second bus lines; a first buffer connected between the first and second bus lines; second and third buffers connected to the first bus line; fourth and fifth buffers connected to the second bus line; first to fourth banks connected via the first, second, and third buffers to the second bus line; fifth to eighth banks connected via the fourth and fifth buffers to the second bus line; and a data input/output unit connected to the second bus line. Transfer delay times of the fourth and fifth buffers are longer than transfer delay times of the first, second, and third buffers. Thereby, it becomes possible to eliminate differences in data transfer times resulting from differences in distances between far and near ends without causing significant increase in wire density, increase in power consumption, or the like.

Abstract: A semiconductor memory device of the present invention determines a logic level of a signal based on a predetermined reference voltage. And the memory device has an input terminal to which a reference signal having the reference voltage is input, a low-pass filter connected to the input terminal for passing a component of the reference voltage of the reference signal and eliminating undesired high frequency components, and one or more input first-stage circuits to each of which an output of the low-pass filter and a signal having the logic level to be determined are connected. In the memory device, the low-pass filter has predetermined attenuation at least at a frequency of an operating clock.

Abstract: A device includes an N-channel transistor for output, a voltage raising circuit, a voltage dropping circuit, and an amplifier. A power supply voltage that is a first voltage is supplied to one end of the output N-channel transistor, and the other end of the output N-channel transistor functions as an output terminal. The voltage raising circuit raises the first voltage to generate a second voltage higher than the first voltage. The voltage dropping circuit reduces the second voltage to generate a third voltage that is higher than the first voltage and is lower than the second voltage. The amplifier amplifies the difference between a reference voltage and a voltage generated at the output terminal, using the third voltage as a power supply voltage, to generate a fourth voltage, and supplies the fourth voltage to the gate of the N-channel transistor for output.

Abstract: To provide a semiconductor device including: first and second bus lines; a first buffer connected between the first and second bus lines; second and third buffers connected to the first bus line; fourth and fifth buffers connected to the second bus line; first to fourth banks connected via the first, second, and third buffers to the second bus line; fifth to eighth banks connected via the fourth and fifth buffers to the second bus line; and a data input/output unit connected to the second bus line. Transfer delay times of the fourth and fifth buffers are longer than transfer delay times of the first, second, and third buffers. Thereby, it becomes possible to eliminate differences in data transfer times resulting from differences in distances between far and near ends without causing significant increase in wire density, increase in power consumption, or the like.

Abstract: A semiconductor storage device is provided which enables use of an overdrive method at low voltage and for a small device area. The semiconductor device includes: memory cells; sense amplifiers, each having P-channel and N-channel MOS transistors and amplifying a signal read from a memory cell; a first power supply line connected to a source terminal of the P-channel MOS transistor provided in each of the sense amplifiers; a second power supply line which supplies an overdrive voltage to the sense amplifiers at a potential higher than a write potential of the memory cell; a third power supply line connected to an external power supply, a connection element which connects and disconnects the first power supply line and the second power supply line; a capacitance element connected to the second power supply line; and a resistance element inserted between the second power supply line and the third power supply line.

Abstract: A semiconductor device operates in an active mode or a standby mode, and includes a substrate-potential power source line supplying a substrate potential which is higher in a standby mode than in an active mode, and a source-potential power source line supplying a source potential which is lower in a standby mode than in an active mode. During a mode shift from the standby mode to the active mode, a potential equalizing transistor is turned ON to pass a current flowing from the substrate-potential power source line to the source-potential power source line, to reduce the time length needed for shifting from the standby mode to the active mode.

Abstract: A semiconductor memory device includes a shared transistor controlling coupling between a bit line pair in a memory cell array and a bit line pair in a sense amplifier. After a word line is activated and the sense amplifier amplifies the potential difference between the bit lines of the bit line pair in the sense amplifier, the shared transistor is tuned OFF and precharge/equalizing circuit is activated to precharge the bit lines in the sense amplifier to a potential which is half the internal power source potential.

Abstract: A semiconductor memory device is provided that is capable of detecting a short circuit defect to be detected in a memory array without causing an error due to off-current of a sense amplifier circuit. Sense amplifier circuits amplify a potential between a pair of bit lines, which occurs based on potential of memory cells selected by driving word lines and bit lines. Selection transistors are provided between the bit lines and the sense amplifier circuits. A word-SE interval control circuit included in an X timing generating circuit turns off the selection transistors and disconnects the bit lines from the sense amplifier circuits based on a signal representing a test state for expanded time when a test to expand an interval between word line driving and activation of the sense amplifier circuits and detect defect sites of the bit lines is performed.

Abstract: A device includes an N-channel transistor for output, a voltage raising circuit, a voltage dropping circuit, and an amplifier. A power supply voltage that is a first voltage is supplied to one end of the output N-channel transistor, and the other end of the output N-channel transistor functions as an output terminal. The voltage raising circuit raises the first voltage to generate a second voltage higher than the first voltage. The voltage dropping circuit reduces the second voltage to generate a third voltage that is higher than the first voltage and is lower than the second voltage. The amplifier amplifies the difference between a reference voltage and a voltage generated at the output terminal, using the third voltage as a power supply voltage, to generate a fourth voltage, and supplies the fourth voltage to the gate of the N-channel transistor for output.

Abstract: A semiconductor memory device is provided that is capable of detecting a short circuit defect to be detected in a memory array without causing an error due to off-current of a sense amplifier circuit. Sense amplifier circuits amplify a potential between a pair of bit lines, which occurs based on potential of memory cells selected by driving word lines and bit lines. Selection transistors are provided between the bit lines and the sense amplifier circuits. A word-SE interval control circuit included in an X timing generating circuit turns off the selection transistors and disconnects the bit lines from the sense amplifier circuits based on a signal representing a test state for expanded time when a test to expand an interval between word line driving and activation of the sense amplifier circuits and detect defect sites of the bit lines is performed.

Abstract: A semiconductor storage device is provided which enables use of an overdrive method at low voltage and for a small device area. The semiconductor device includes: memory cells; sense amplifiers, each having P-channel and N-channel MOS transistors and amplifying a signal read from a memory cell; a first power supply line connected to a source terminal of the P-channel MOS transistor provided in each of the sense amplifiers; a second power supply line which supplies an overdrive voltage to the sense amplifiers at a potential higher than a write potential of the memory cell; a third power supply line connected to an external power supply, a connection element which connects and disconnects the first power supply line and the second power supply line; a capacitance element connected to the second power supply line; and a resistance element inserted between the second power supply line and the third power supply line.

Abstract: A semiconductor device operates in an active mode or a standby mode, and includes a substrate-potential power source line supplying a substrate potential which is higher in a standby mode than in an active mode, and a source-potential power source line supplying a source potential which is lower in a standby mode than in an active mode. During a mode shift from the standby mode to the active mode, a potential equalizing transistor is turned ON to pass a current flowing from the substrate-potential power source line to the source-potential power source line, to reduce the time length needed for shifting from the standby mode to the active mode.

Abstract: A semiconductor memory device includes a shared transistor controlling coupling between a bit line pair in a memory cell array and a bit line pair in a sense amplifier. After a word line is activated and the sense amplifier amplifies the potential difference between the bit lines of the bit line pair in the sense amplifier, the shared transistor is tuned OFF and precharge/equalizing circuit is activated to precharge the bit lines in the sense amplifier to a potential which is half the internal power source potential.

Abstract: A semiconductor memory device of the present invention determines a logic level of a signal based on a predetermined reference voltage. And the memory device has an input terminal to which a reference signal having the reference voltage is input, a low-pass filter connected to the input terminal for passing a component of the reference voltage of the reference signal and eliminating undesired high frequency components, and one or more input first-stage circuits to each of which an output of the low-pass filter and a signal having the logic level to be determined are connected. In the memory device, the low-pass filter has predetermined attenuation at least at a frequency of an operating clock.

Abstract: When a DLL circuit using a clock is employed, the internal power supply circuit is arranged between the external power supply and the DLL circuit. The internal power supply circuit supplies power from the external power supply after reducing the voltage thereof. The internal power supply circuit is divided into a basic power supply circuit and an additional power supply circuit. The internal power supply circuit further includes a frequency determination circuit, which samples the clock to detect the frequency thereof, and generates a determination signal based on the detected frequency. Based on the determination signal, the internal power supply circuit controls the connection or disconnection of the additional power supply circuit. The basic power supply circuit and the additional power supply circuit are activated in a high frequency range, whereas only the basic power supply circuit is activated in a low frequency range.