摘要:
An EEPROM capable of arbitrarily setting a write time includes a timer circuit connected to a trimming circuit for determining a write time, and a trimming redundant memory array used for storing trimming data to be supplied to the trimming circuit in accordance with a predetermined write time so that the write time can be arbitrarily set. A series of calibration operations are performed such that the trimming data is read from the trimming redundant memory and supplied to the trimming circuit and the timer circuit is controlled so as to set the write time to a desired value. The latter operation is carried out in parallel to a normal write operation. Accordingly, neither special instructions nor an additional time period are required to perform the calibration operation, and a stable operation can be achieved in less time.
摘要:
A MISFET is provided with a segmented channel comprising regions in which the channel is inverted by a first gate voltage and regions in which the channel is inverted by a second gate voltage. The MISFET is formed in a semiconductor substrate having a first conductivity type and the first inversion region of the channel has a first impurity concentration determined by the surface concentration of the substrate. The second inversion region of the channel has a second impurity concentration determined by doping an impurity to the region selected by a photolithographic process. The first and second inversion regions may be divided into a plurality of plane shapes and the threshold voltage of the MISFET is set to a desired value in accordance with the plane area ratio of the first and second inversion regions.
摘要:
An EEPROM operable at a reduced power source voltage comprises a decoder circuit for decoding input signals, a memory array for storing the decoded, a reading circuit for operating the decoder circuit and the memory array, and for reading out data stored in the memory array, and a writing circuit for operating the decoder circuit and the memory array, and for writing data to the memory array. The EEPROM is divided into a first circuit area comprising a plurality of first transistors driven by a first power source voltage, an absolute value of a threshold voltage of the first transistors in the first circuit area being within the range of approximately 0.3 V to 0.7 V, the first circuit area including at least the reading circuit, and a second circuit area comprising a plurality of second transistors driven by a second power source voltage, an absolute value of a threshold voltage of the second transistors in the second circuit area being within the range of approximately 0.7 V to 0.9 V, the second circuit area including at least the writing circuit.
摘要:
In a MISFET, areas where a channel surface of a channel region is inverted by a first gate voltage and areas where the channel surface is inverted by a second gate voltage are provided in the channel region of the MISFET in plane as components thereof. The channel region 104 having a first impurity concentration determined by a surface concentration of a P-type semiconductor substrate and a channel region 105 having a second impurity concentration determined by doping an impurity to the region selected by a pattern 106 of a mask for doping impurity by ion implantation and others are provided in a channel region of an N-type MOSFET on the P-type semiconductor substrate. The channel region 104 having the first impurity concentration and the channel region 105 having the second impurity concentration are divided into a plurality of plane shapes. The channel region of the same MOSFET may be structured by the plurality of plane shapes having the plurality of impurity concentrations as described above and a threshold voltage of the MOSFET may be readily set to a desired value in response to a plane area ratio of the area having the first impurity concentration and the area having the second impurity concentration, allowing to realize a high performance semiconductor integrated circuit device at low cost.
摘要:
An object of the present invention is to provide a powder supply nozzle and an overlaying method which make it possible to restrain oxidation of a clad layer part and to produce a clad layer part with high quality. The invention provides a powder supply nozzle including: a laser emission part for irradiating a workpiece with a laser beam; and a powder supply part disposed in the periphery of the laser emission part and adapted to discharge a powder onto a laser-irradiated part, wherein a mechanism for guiding the air surrounding the laser-irradiated part to the exterior of the laser-irradiated part is provided in the periphery of the powder supply part.
摘要:
In an integrated circuit having two circuits operating at different power supply voltages a level shifter, which transmits a signal from a high voltage operation circuit to a low voltage operation circuit, is composed of a depletion NMOS transistor with its gate electrode fixed to the potential of the power supply voltage of the low voltage operation circuit.
摘要:
A latch circuit is arranged by means for detecting a signal, a unit for holding a signal detection condition, and a unit for releasing the signal detection condition. When a detection output produced from the detecting unit is entered into the signal detection condition holding unit, the signal detection condition holding unit continuously holds the detection condition until a power supply is interrupted even when the detection output is not entered thereinto. The signal detection condition releasing unit produces a release signal only when the power supply is turned ON. Once the signal detection condition holding unit holds the signal detection condition, the signal detection condition holding unit is reset to an undetection condition only when the power supply is interrupted and then is again turned ON. The latch circuit can firmly reset the stopped system to the initial condition by merely again turning ON the power supply. In addition the stopped system is not unnecessarily reset until the power supply is interrupted. As a consequence, it is possible to obtain the safety operation as well as the firm operation of the circuit and the system.
摘要:
A memory circuit is provided which is capable of writing data with a simplified configuration and hence being improved in usability. The present invention comprises a fuse 10 having one end to which a bias voltage Vcc is to be applied from an internal power supply to have a disconnect/connect state storing data 0/1, a thyristor 11 having an anode terminal connected to the internal power supply through the fuse 10 and a cathode terminal being ground, an N-channel MOS transistor 12 having a drain terminal connected to a gate terminal of the thyristor 11 and a source terminal being ground, and a read-out circuit 14 for reading out data 0/1 stored on the fuse 10 through the N-channel MOS transistor 13.
摘要:
There is provided a voltage detecting circuit in which a consumed electric current is small, accuracy is high, and an erroneous operation seldom occurs. In the voltage detecting circuit constituted by a bias circuit, a current mirror circuit, a load MIS transistor connected to the current mirror circuit in which current drive capability is changed by an output voltage of the bias circuit, and an amplifying inverter circuit, a potential change at an output node of the current mirror circuit at the time of detection and release of a power supply voltage is steeply changed, so that a leak current of the whole circuit can be decreased and a consumed electric current can be reduced. Besides, plural load P type MIS transistors of the bias circuit are prepared, so that a detection voltage and a release voltage can be made to have hysteresis, abnormal oscillation of a detection output VDETX in the vicinity of the detection and release voltage can be prevented, and an erroneous operation of a logic circuit to which the detection output is applied can be prevented.
摘要:
In a non-volatile memory capable of electrically rewriting data, a timer circuit for determining writing time that is operable at any time at a voltage of under 1.0 V. The timing circuit has a regulated voltage circuit for outputting a regulated output voltage no greater than 1.0 V, a constant current circuit for producing a constant current having a value determined by the regulated output voltage, a voltage comparing circuit for comparing an input voltage input to one terminal with a reference voltage input to another terminal, and a capacitive element connected to a constant current output terminal of the constant current circuit. A connecting point of the constant current output terminal of the constant current circuit and the capacitive element is connected as the input voltage to the voltage comparing circuit, so that a desired time period is determined by comparing a voltage to the terminal of the voltage comparing circuit connected to the capacitive element with the reference voltage connected to the other terminal of the comparing circuit.