Abstract: A power supply circuit comprising a reference voltage generating circuit and an internal voltage generating circuit, whereby a stable internal voltage can be supplied. The reference voltage generating circuit comprises a resistor, of which one end is coupled to a power supply terminal, and a first NMOSFET, of which the drain electrode is coupled to the other end of the resistor, the source electrode is coupled to an earth terminal, and the gate electrode is coupled to the drain electrode. The internal voltage generating circuit comprises a second NMOSFET, of which the gate electrode is coupled to the drain electrode of the first NMOSFET and the source electrode is coupled to the earth terminal, and a constant voltage generating circuit, coupled between the drain electrode of the second NMOSFET and the power supply terminal, which outputs a constant voltage. The gate length of the first NMOSFET is formed longer than the gate length of the second NMOSFET.

Abstract: In semiconductor memory device having a plurality of memory cell arrays in which a potential difference between a pair of bit lines to which memory cells are connected is amplified by a sense amplifier operating responsive to a sense latch signal on a common node, and the memory cells are connected via a power supply line to a power supply, the adverse effects due to the resistance of the power supply line is eliminated or reduced. This is achieved by coupling a power supply auxiliary line disposed within each memory cell array and a power supply main line disposed along the memory cell arrays by means of a resistive element having a resistance larger than the resistance of the power supply main line from the power supply to the memory cell array located farthest. Alternatively, the common node in each memory cell array is connected to said power supply main line via a resistive element and a sense amplifier drive transistor which is turned on and off by a control signal.

Abstract: In semiconductor memory device having a plurality of memory cell arrays in which a potential difference between a pair of bit lines to which memory cells are connected is amplified by a sense amplifier operating responsive to a sense latch signal on a common node, and the memory cells are connected via a power supply line to a power supply, the adverse effects due to the resistance of the power supply line is eliminated or reduced. This is achieved by coupling a power supply auxiliary line disposed within each memory cell array and a power supply main line disposed along the memory cell arrays by means of a resistive element having a resistance larger than the resistance of the power supply main line from the power supply to the memory cell array located farthest. Alternatively, the common node in each memory cell array is connected to said power supply main line via a resistive element and a sense amplifier drive transistor which is turned on and off by a control signal.

Abstract: An integrated circuit semiconductor memory device includes a memory array having memory cells. A sensing circuit is coupled to the memory cells through one of first and second bit lines. A first conductive line is for applying a first voltage potential to the sensing circuit, and a second conductive line is for applying a second voltage potential to the sensing circuit. A first field effect transistor is provided having first, second electrodes connected to the first conductive line, and a gate electrode connected to the second conductive line. The sensing circuit has a second field effect transistor and a third field effect transistor of an opposite channel type to the second field effect transistor. The first, second and gate electrodes of the first field effect transistor are formed substantially simultaneously with the first, second and gate electrodes of one of the second and third field effect transistors during manufacture of the integrated circuit semiconductor memory device.

Abstract: A data bus clamping circuit for use in a semiconductor memory device includes a memory cell array for storing data, a row address decoder for decoding row address signals taken in by a row address strobe signal to select memory cells in a row direction of the memory cell array, a column address decoder for decoding column address signals based on a column address decoder enabling signal to select memory cells in a column direction of the memory cell array, complementary data buses for transmitting data read out from the memory cell array, a data bus pull-up circuit for pulling up the complementary data buses, and a differential amplification type of readout circuit for amplifying on a differential basis data on the complementary data buses to output readout data.

Abstract: A CMOS memory device has a memory cell array, formed on a substrate of a first conductive type, for storing data. The data are input and output via bit line pairs connected to the memory cell array. Sense amplifiers of the first conductive type, which are embedded in wells of a second conductive type, amplify potential differences on the bit line pairs. The sense amplifiers are connected to and driven by a sense amplifier drive signal line. The sense amplifier drive signal line also biases the wells containing the sense amplifiers, thereby preventing latch-up.

Abstract: A data bus clamping circuit for use in a semiconductor memory device includes a memory cell array for storing data, a row address decoder for decoding row address signals taken in by a row address strobe signal to select memory cells in a row direction of the memory cell array, a column address decoder for decoding column address signals based on a column address decoder enabling signal to select memory cells in a column direction of the memory cell array, complementary data buses for transmitting data read out from the memory cell array, a data bus pull-up circuit for pulling up the complementary data buses, and a differential amplification type of readout circuit for amplifying on a differential basis data on the complementary data buses to output readout data.

Abstract: A CMOS memory device has a memory cell array, formed on a substrate of a first conductive type, for storing data. The data are input and output via bit line pairs connected to the memory cell array. Sense amplifiers of the first conductive type, which are embedded in wells of a second conductive type, amplify potential differences on the bit line pairs. The sense amplifiers are connected to and driven by a sense amplifier drive signal line. The sense amplifier drive signal line also biases the wells containing the sense amplifiers, thereby preventing latch-up.

Abstract: A memory circuit has a Vcc post that is connected to a Vcc pad and is optionally connectable to a mode pad. The memory circuit also has N data output buffers, M of which operate regardless of whether the Vcc post is connected to the mode pad or not. These M data output buffers are all powered from the Vcc pad. The remaining N-M data output buffers operate only when the Vcc post is connected to the mode pad; at least one of these N-M data output buffers is powered from the mode pad, thereby reducing the potential drop at the Vcc pad.

Abstract: A drive circuit for driving a semiconductor device includes a reference voltage level generator for outputting a reference voltage level which is associated with an input voltage level from an external power source. Supplied with the reference level, a ring oscillator oscillates a frequency signal having a predetermined frequency. A drive voltage level generator responds to the reference level and the frequency signal for producing a drive voltage level which is constantly substantially equal to the reference level in synchronism with the frequency signal. The drive voltage level generator feeds power from the external power source to the semiconductor device at the drive level, thereby driving the semiconductor load circuit.