Abstract: In a dynamic sensing-type nonvolatile semiconductor memory device of the invention, which employs a differential sense amplifier circuit, a memory cell is connected to a bit line using a word line and a reference memory cell is connected to an anti-bit line using a reference word line, the potential difference between the bit line and the anti-bit line is amplified by a sense amplifier, and when reading the data of the memory cell, at the start of data readout the bit lines are both precharged to a predetermined potential by a precharge circuit, and during and after precharging or only after precharging is finished, an identical amount of current is supplied to the bit line and the anti-bit line by a bit line current supply circuit.

Abstract: A novel communications system is provided, including a plurality of user terminals capable of communication using a predetermined communication software program and accessible to Internet, and an administrator server on line with Internet, wherein each of the user terminals is capable of transmitting a character message comprising character information for designating a character, action information for designating an action of the character and a text message to another user terminal through Internet via the administrator server with use of the communication software program, while the latter user terminal having received the character message is capable of displaying an image of the character performing the action and the text message on a screen by selecting a motion picture file based on the character information and the action information received using the communication software program and executing the motion picture file.

Abstract: The present invention provides a controller for driving an electric vehicle including a small filter having sufficient attenuation characteristics in order to avoid the adverse influence of the higher harmonic component contained in the return wire current flowing through a rail exerted on the safety equipment for railway or the like provided therein. In a controller for driving an electric vehicle including an inverter 6 supplied with the electric power through a D.C. filter 5, in the D.C. filter 5, two reactors 51a and 51b having the magnetic coupling are connected in series to ensure effectively an inductance, to realize miniaturization and also to make the near-place installation possible.

Abstract: To read data stored on a memory cell transistor with a floating gate, a flash memory uses: a single-gate reference transistor; a differential sense amplifier; and a gate voltage generator for generating a gate voltage for the reference transistor. The gate voltage generator includes: a dummy cell transistor, which has the same structure as the memory cell transistor and has been turned ON; a current mirror for creating a current proportional to a drain current of the dummy cell transistor; an NMOS transistor for generating a gate voltage for the reference transistor in accordance with the current created by the current mirror; and a voltage hold circuit for holding the gate voltage generated. Even if temperature or fabricating process conditions have changed, this construction ensures accurate and high-speed read operation.

Abstract: In order to read a data stored in a given memory cell, two dummy cells are provided, one of which is set to an erase state and the other to a program state. The threshold voltage of each cell attained in the program state is higher than the threshold voltage attained in the erase state and is lower than a maximum read voltage applied between a control gate and a source. Bit lines connected to the drains of the dummy cells are mutually connected through an equalizing switch for generating a reference potential at an intermediate level in a read cycle. The potential of a bit line connected to the drain of the memory cell and the generated reference potential are compared by a differential sense amplifier, so as to sense the state of the memory cell. In this manner, the invention provides a flash memory in which a program operation completed in short time and an accurate read operation can be consistent with each other.

Abstract: To read data stored on a memory cell transistor with a floating gate, a flash memory uses: a single-gate reference transistor; a differential sense amplifier; and a gate voltage generator for generating a gate voltage for the reference transistor. The gate voltage generator includes: a dummy cell transistor, which has the same structure as the memory cell transistor and has been turned ON; a current mirror for creating a current proportional to a drain current of the dummy cell transistor; an NMOS transistor for generating a gate voltage for the reference transistor in accordance with the current created by the current mirror; and a voltage hold circuit for holding the gate voltage generated. Even if temperature or fabricating process conditions have changed, this construction ensures accurate and high-speed read operation.

Abstract: A nonvolatile semiconductor memory device includes: first and second memory cell blocks, each of the first and second memory cell blocks including at least one memory cell connected to a first word line; third and fourth memory cell blocks, each of the third and fourth memory cell blocks including at least one memory cell connected to a second word line; and an amplifier for inputting or outputting data through first and second bit lines. Each said memory cell block includes at least one dummy cell.

Abstract: To obtain a control apparatus for a Diesel-electric locomotive that harmonizes an engine power with a torque command of an induction motor, which is a load of an engine, in the Diesel-electric locomotive and avoids an overload of the engine.A cooperative controller 15 is provided, the controller 15 which receives a notch signal N, an engine speed command value n* corresponding to the notch signal N, an engine speed n, and rotating speed fr of an induction motor 17, calculates a torque command value Tp corresponding to the engine speed n from torque command values before and after the notch signal changing during response time for control of the engine speed if the notch signal N changes, and calculates the torque command value Tp corresponding to the notch signal N after a notch is changed, except the case thereof. Furthermore, the torque command value Tp is outputted to an inverter controller 20.

Abstract: A control system of a vehicle automatic transmission in which an engine load and a vehicle speed are detected and used to determine a vehicle acceleration in accordance with the pre-established characteristics. An actual vehicle acceleration is at the same time calculated in response to the detected vehicle speed. The difference therebetween is then calculated and the calculated value is added to a difference calculated earlier to obtain an average therebetween. Five gear shifting scheduling maps, for example, one for moderate hill climbing, one for level-road running, one for steep hill descent, are pre-established and in response to the average obtained, one of the maps is selected. A gear shifting is controlled based on the selected map. In a pre-determined condition, such as when the engine load changes abruptly, braking is in progress and so on, the map selection is suspended and the control is carried out using the map selected earlier.

Abstract: In a method of controlling the output voltage of a three-phase three-level inverter having a plurality of switching elements by pulse width modulation in each of three-pulse and one-pulse modes, the upper limit of the percentage modulation is set to a value equal to or smaller than the maximum percentage modulation determined by the minimum switching element off time to output a three-level voltage as an inverter output voltage in each phase if each of the switching element is turned of and off one time during one inverter output period.

Abstract: A method of controlling a three-phase, three-level inverter comprises the steps of: jugding whether the current of the output terminal of an inverter of the phase such that the electrical potential of the output terminal equals to the neutral-point terminal of the capacitor among three-output terminals of the inverter is in a positive direction in which current flows into a load connected to this output terminal or in a negative direction in which current flows from the load when another on/off mode having the same instantaneous space voltage vector as the instantaneous space voltage vector in a tentatively selected on/off mode exists; actually selecting the tentatively selected on/off mode if the result of the judgment is positive and actually selecting another on/off mode instead of the tenatively selected on/off mode when the result of the judgement is negative in the case where the electrical potential of the neutral-point terminal of the capacitor is above a preset upper-limit value; and actually selecti

Abstract: A magnetic disc driving apparatus for positioning a magnetic head by a servomechanism, which, when control mode of positioning control is switched from speed control to tracking control, switches the tracking control to open-loop control by an optimum compensation quantity at the position and speed of the magnetic head and holds open-loop control for a predetermined time, and which, after the lapse of predetermined time, returns the tracking control to closed-loop control, thereby restricting overshoot of the magnetic head caused during the tracking control and reducing a settling time.