787 results about "Threshold current" patented technology

In a semiconductor laser having an active layer of double-quantum-well structure that includes two InGaN well layers each of which has a thickness of 5 nm, a threshold current deteriorates to a relatively small degree while differential efficiency is improved considerably in a region having a light confinement coefficient Γ of 3.0% or less. On the other hand, with the light confinement coefficient Γ becoming less than 1.5%, the threshold current increases considerably while the amount of improvement in differential efficiency becomes small. It is therefore preferable that the lowest limit to the light confinement coefficient Γ be about 1.5%. The differential efficiency of 1.6 W/A or more is obtained with the light confinement coefficient Γ being 3.0% or less, and the differential efficiency of 1.7 W/A or more is obtained with the light confinement coefficient Γ being 2.6% or less.

A magnetic memory element switchable by current injection includes a plurality of magnetic layers, at least one of the plurality of magnetic layers having a perpendicular magnetic anisotropy component and including a current-switchable magnetic moment, and at least one barrier layer formed adjacent to the plurality of magnetic layers (e.g., between two of the magnetic layers). The memory element has the switching threshold current and device impedance suitable for integration with complementary metal oxide semiconductor (CMOS) integrated circuits.

A free electron laser for generating a Smith-Purcell radiation. In one embodiment, the free electron laser includes a grating having a grating surface, an electron emitter for generating a beam of electrons, and a guiding member positioned therebetween the electron emitter and the grating for directing the beam of electrons along a path extending over the grating surface of the grating with a focal point so that in operation a Smith-Purcell radiation and an evanescent wave are generated by interaction of the beam of electrons with the grating. In operation, the beam current of the beam of electrons is equal to or greater than a threshold current and the group velocity of the evanescent wave is substantially close to zero or negative so that the evanescent wave travels backward to allow electrons in the beam of electrons are bunched by interaction with the evanescent wave to substantially enhance the Smith-Purcell radiation over the range of wavelengths.

Systems and methods for providing overcurrent circuit protection are disclosed. A method of providing overcurrent circuit protection may include setting a threshold current value according to an operational state of a motor and sensing an amount of current being supplied to the motor. The method may further include electrically isolating the motor from a current source if the sensed current amount is greater than the threshold current value.

A bus power device includes a connector that is connected to a port of a host apparatus compliant with a predetermined interface standard; a current/voltage detecting unit that detects a current/voltage supplied from the host apparatus to a bus power line via the port and the connector; and a power assisting unit that assists a current to the bus power line based on a result of comparison between the current detected by the current/voltage detecting unit and a threshold current, and assists a voltage to the bus power line by an amount of shortfalls in the voltage based on a result of comparison between the voltage detected by the current/voltage detecting unit and a threshold voltage.

The invention relates to a drive circuit for an injector arrangement comprising a fuel injector, and method of detecting faults in the drive circuit. The drive circuit comprises diagnostic means (R_H, R_L) that is operable to sense a measured voltage (V_BIAS) between the injector and a known voltage level (V_BAT, V_GND). The measured voltage (V_BIAS) is biased with respect to the known voltage (V_BAT, V_GND) to a predicted voltage (V_PinjN, V_Bcalc) unless the drive circuit has a fault. A fault signal is provided on sensing of a measured voltage (V_BIAS) that differs from the predicted voltage (V_PinjN, V_Bcalc). The drive circuit may additionally, or alternatively, comprise diagnostic means (R_F). The diagnostic means (R_F) is operable to sense a detected current (I_dect) and to provide a fault signal on detection of a fault, when the detected current (I_dect) is at variance from a threshold current (I_trip).

A laser driver circuit includes a biasing current source, a threshold current source, and a modulation current source, wherein the threshold current source produces a threshold current in response to an input signal with an interval exceeding an interval of a modulation current such that said interval of the threshold current includes the interval of said modulation current. The laser driver circuit drives the laser diode by a sum of a continuous bias current, the threshold current and the modulation current.

A magnetic memory device comprises a magnetic tunnel junction (MTJ) having a ferromagnetic free layer, and exhibits a first, relatively high resistance state, and a second, relatively low resistance state. To write to the magnetic memory device a current I_MTJ is driven through the MTJ. For a first duration, the current is equal to a DC threshold current, being the DC current required to switch the multilayer structure between the first state and the second state. This induces a C-like domain structure in the free layer. For a second duration, the current I_MTJ is larger than the DC threshold current. This causes the MTJ to switch states. The current requited to cause switching is less than that required using a uniform current pulse.

A TRIAC dimmer controller for an LED lamp dynamically adjusts the amount of additional current supplied to the TRIAC dimmer based on the TRIAC dimmer operating mode. A TRIAC dimmer current controller continually senses the TRIAC dimmer current loading and determines a TRIAC dimmer operating mode based on the detected current. The TRIAC dimmer controller compares the detected current with a threshold current value called a TRIAC holding current, and adjusts the amount of bleeder current based on the difference between the detected current and the threshold current value. By continually sensing the TRIAC dimmer current loading, the LED controller regulates the amount of bleeder current supplied to the TRIAC dimmer using a single sink current path to satisfy the TRIAC dimmer current demands of multiple TRIAC dimmer operating modes.

The present invention is directed to systems for evaluating one-time programmable memory cells. A threshold current is applied to a resistive circuit, thereby generating a threshold voltage. A read current is applied to a first memory cell, thereby generating a memory cell voltage. The memory cell voltage is compared to the threshold voltage, thereby determining the state of the memory cell. In a further embodiment of the invention, a second threshold voltage is generated and compared the memory cell voltage, thereby verifying the state of the memory cell. The threshold current is optionally a substantial replica of said read current. The threshold current is optionally a proportional substantial replica of said read current. In an embodiment, the resistive circuit includes a second memory cell, which can be programmed or unprogrammed. The second memory cell is optionally arranged to average the memory cell resistance.

Provided are highly reliable information processing equipment enabling a high recording density, and a blue color, blue-violet color and violet color based semiconductor light emitting device operable at a low threshold current density, which device is suitable for the information processing equipment. According to the present invention, there can be realized highly reliable optical information processing equipment enabling high recording density, which is capable of sufficiently recording or reproducing a dynamic image in or from a high-definition TV.An n-type impurity is doped in a barrier layer of a quantum-well active layer of a semiconductor light emitting device at a high density. Alternatively, the oriented plane of a quantum-well active layer of a semiconductor light emitting device is inclined from the (0001) plane, whereby the threshold current value of the semiconductor light emitting device can be reduced. The semiconductor light emitting device is represented by a gallium nitride based compound semiconductor laser device.

An ion current detection device of an internal combustion engine includes a detection voltage generation device which applies a voltage to an ignition plug to generate an ion current in a cylinder of the engine. A current to voltage conversion circuit detects and converts the generated ion current to a voltage signal. A bandpass filter extracts an ac component within a specified frequency range from the voltage signal produced by the current to voltage conversion circuit. An ion current threshold detection portion produces an ion current detection signal when the detected ion current exceeds a predetermined threshold current. A filter characteristic control circuit controls the characteristic of the bandpass filter to suppress the sensitivity of the filter for a predetermined period of time right after the ion current detection signal is detected and, after the predetermined period of time, increase the sensitivity of the filter for detection of the ac signal with the specific frequency.

Between the value of an electric current and the supply duration for which the electric current is supplied that cause magnetization reversal, there is the relation of monotonous decrease. This means that, as the supply duration is shortened, the threshold current value for causing the magnetization reversal is larger. Therefore, in terms of suppressing occurrence of read disturb, the read current supply duration may be shortened to increase the threshold value of the current causing the magnetization reversal and thereby ensure a sufficient read disturb margin. Therefore, the read current supply duration may be shortened relative to the write current supply duration ensure the read disturb margin and suppress occurrence of read disturb.

In a method and an apparatus for controlling AC pulse arc welding executed by supplying a welding current flowing between a welding wire and an object to be welded with feeding the welding wire at a feeding speed corresponding to a predetermined feeding speed setting signal, a one-period process for supplying the welding current is repeatedly executed. The one-period process includes a first process during a peak time interval, a second process during a negative electrode time interval, and a third process during a base time interval. The one-period process further includes a fourth process during a switching current interval, inserted between the peak time interval and the negative electrode time interval, for supplying a welding current having a switching current for stopping growth of droplet which is smaller than a threshold current with a positive electrode polarity.