1990 results about "Current generator" patented technology

A LED driver is connectible to several series connected RGB LEDs which connect in series with a current generator. A plurality of LED switches are respectively connectible across one RGB LED. Each LED switch, operating in response to a binary signal is either open to permit electrical current to flow through the RGB LED, or closed to shunt current around that RGB LED. By varying respective duty cycles of the binary signals the LED driver is adapted for controlling operation of the combined RGB LEDs so they emit differing colors of light. An adaptive boost converter LED driver continuously adjusts voltage applied across the series connected RGB LEDs to be only that required for operating those LEDs through which open LED switches permit current to flow.

The display comprises an array of pixel circuits each comprising an emitter 1 in series with a current modulation transistor, and at least one address circuit, which integrates, for each column, a differential amplifier and a passive element preferably a resistive element, which cooperate with the current modulation transistors so as to form, during address phases in which the emitters are switched “out of the circuit”, a voltage-programmable current generator. After the address phases, thanks to a suitable switch, the emitters are switched “into the circuit” and supplied with the preprogrammed current. Such a display allows the image display quality to be inexpensively improved.

A pad assembly according to the invention is used for mounting a current generator for applying a therapeutic electrical current to an area of human skin. Such an assembly includes a pad comprising a thin, flexible, stretchable plastic film that conforms to human skin, which pad has electrical paths printed on an underside thereof with electrically conductive ink. Each of the paths include a terminal and a conductive contact for connection to a current generator. A pair of layers of an electrically conductive adhesive such as a hydrogel are disposed over the terminals at spaced positions for conducting electrical current to human skin underlying the terminals. A fixture secured to the pad is configured for mounting the current generator a manner effective to conduct current from the current generator to the terminals of the pad.

An integrated welder, generator and hydraulic unit that includes a housing that at least partially contains components of a welder, generator and a hydraulic pump. An engine, an electric current generator, and a hydraulic pump are at least partially mounted in the housing. The electric current generator is at least partially connected to the engine to be at least partially driven thereby. The hydraulic pump can be at least partially powered by the electric current generator or the fuel powered engine during the operation of the engine. The integrated welder, generator and hydraulic unit can also include an air compressor.

A phase change memory has an array formed by a plurality of cells, each including a memory element of calcogenic material and a selection element connected in series to the memory element; a plurality of address lines connected to the cells; a write stage and a reading stage connected to the array. The write stage is formed by current generators, which supply preset currents to the selected cells so as to modify the resistance of the memory element. Reading takes place in voltage, by appropriately biasing the selected cell and comparing the current flowing therein with a reference value.

An apparatus for locating and anesthetizing a nerve enables an anesthesiologist to perform a nerve blockade procedure without an assistant. An anesthetic-filled syringe is releasably mounted to a hands-free, foot-actuated, hydraulic syringe controller. An electric current generator is mounted to the syringe controller and operatively connected to a needle of the syringe. A hands-free, foot-actuated current generator controller determines an amperage of an electrical stimulus output to the needle. The current generator includes audible and visual displays for informing the anesthesiologist of the output amperage. Because the syringe controller and current generator controller allow hands-free operation, an anesthesiologist can continuously use both hands to manipulate and hold the needle in a patient.

An offshore power generator is disclosed. The offshore power generator includes an offshore platform, which can be a new, existing, abandoned, removed, dumped or relocated fixed or floating offshore platform; one or more types of current, wind, wave and other renewable energy generators mounted to the offshore platform; and interconnecting power cables, in electrical communication with the current generators for distribution from the generators to end users.

A voltage reference circuit including a positive temperature coefficient current generator, a negative temperature coefficient current generator, and a first resistor is provided. In the positive temperature coefficient current generator, two transistors are operated in the weak inversion region, and a second resistor is connected in series between the gates of the two transistors. The second resistor employs the characteristic that a transistor operated in weak inversion region acts like a bipolar junction transistor to generate a positive temperature coefficient current. The negative temperature coefficient current generator generates a negative temperature coefficient current in response to a negative temperature coefficient voltage drop on a third resistor. The positive temperature coefficient current and the negative temperature coefficient current flow through the first resistor together, thus producing a stable reference voltage.

A handheld head treatment device and method for reducing hair loss and stimulating hair growth by supplying current and laser light to a user's head. The device includes a current generator disposed within a housing configured to output a current for passage into the user's head and a laser source and guide means disposed within the housing configured to output and direct respective portions of the laser beam outward from the hair treatment device toward the user's head when the hair treatment device is in use. The method comprises the step of directing a series of different current and laser treatments to a portion of the scalp wherein the programmed current treatments are sequentially administered and include a continuous and pulsed direct current treatment.

A data driver for a display includes a reference current generator that is configured to generate L gray scale reference currents, the L gray scale reference currents being associated with non-zero gray scale levels, a gamma selection module that is configured to select M gamma reference currents from the L gray scale reference currents responsive to a gamma signal, a gamma voltage generator that is configured to generate a zero gray scale level gamma reference voltage, and a data current generator that is configured to generate a data current responsive to a selected one of the M gamma reference currents or the zero gray scale level gamma reference voltage responsive to a color signal.

A fast start-up low-voltage bandgap voltage reference circuit is proposed. The bandgap voltage reference circuit comprises: a first current generator, which is implemented by a self-bias unit and a current mirror for generating a first reference current with positive temperature coefficient; a second current generator, which is connected to a point with negative temperature coefficient in the first current generator to generate a second reference current with negative temperature coefficient; and a resister for converting the first reference current and the second reference current into a low-voltage bandgap voltage independent of temperature. Because the bandgap voltage reference circuit of the invention uses the resistor to convert the first reference current and the second reference current into voltage, the circuit can provide low-voltage bandgap voltage.

The invention provides an impact characteristic simulation test apparatus of an earthing device and a method thereof, and belongs to the simulation test field of the earthing device. The impact characteristic simulation test apparatus comprises an impact current generator, a semispherical test bath, a simulation earthing device, a core penetration type current sensor, an impact voltage divider, a wideband digital oscilloscope, a coaxial shielding cable and the like. According to the method, by employing the apparatus in the invention, an impact simulation test of the earthing device is carried out. According to the invention, a soil discharge process that a real lightning current goes through the earthing device and flows to surrounding soil is simulated accurately, and an impact earthing impedance of the earthing device and an impact flow rule of the earthing device are measured. The apparatus has the characteristics of high reliability, good security, low test cost and the like. The apparatus and the method can be widely applied to measurement of the impact impedance and the impact flow rule of the earthing device under an effect of a heavy impact current, and are especially suitable for measurement of the impact impedance and the impact flow rule of the earthing device under an effect of a lightning current.

A control apparatus of a single-phase power converter for a photovoltaic power generation system is disclosed, including a POS MPPT controller for calculating a rating current by applying a POS MPPT control method to an output current detected through a current transformer of a single-phase AC filter, a bandpass filter for filtering only signals of a low-frequency band from a load, a single-phase reference current generator for producing a reference current by matching a phase of the current from the POS MPPT controller to a phase from the bandpass filter, a single-phase current subtractor for subtracting an output current of a current transformer from the reference current calculated by the single-phase reference current generator to thereby calculate a difference current between the output current of the current transformer and the reference current, a PI controller for outputting a control signal, corresponding to the difference current from the single-phase current subtractor, to a PWM signal generator, and the PWM signal generator for generating a PWM phase control signal corresponding to the control signal from the PI controller.

A radar level gauge for measuring a level of a surface of a product in a tank having a two-wire process control loop, output circuitry coupled to the two-wire process control loop for setting in the loop a desired value of a loop current (Iloop) corresponding to the product level, a power supply circuitry coupled to the two-wire process control loop for receiving power from the loop and being a source of power for a microwave source, a microwave receiver, a measurement circuitry and the output circuitry and including a converter for transferring power from the loop to said power supply circuitry by means of feeding a first current (IDC/DC) from the loop to the power supply circuitry, a current generator included in said output circuitry for generating in parallel to said first current a second current (Ish) in the loop for maintaining said loop current at a value corresponding to said product level and a sensing circuit for determining the value of said second current and having an output indicative of the value of said second current.

An integrated welder, generator and compressor unit that includes a housing that at least partially contains components of a welder, generator and an electric compressor. An engine, an electric current generator, and an electric air compressor are at least partially mounted in the housing. The electric current generator is at least partially connected to the engine to be at least partially driven thereby. The electric air compressor can be at least partially powered by the electric current generator during the operation of the engine. Alternatively, the air compressor can be powered by an external source of power without the use of the engine/generator.

A constant current controller for a constant current power module, including: a demagnetization sensing unit, used for detecting the voltage variation of a detection signal to generate a discharging time signal having an active period corresponding to a secondary side discharging time, wherein the detection signal is derived from an auxiliary coil; a secondary side current sensing unit, used for detecting a peak value of a current sensing signal, and providing an output current according to the peak value of the current sensing signal under the control of the discharging time signal, wherein the current sensing signal is corresponding to a primary side current; and an error current generator, used for generating an error current according to the difference between the output current and a reference current, wherein the error current is converted to a threshold voltage by a first capacitor.

A device for bleaching a part of the human body has a wave-current generator, a plurality of electrodes and a conductive gel. The conductive gel is maintained in contact with the part of the body. An active product is cooperative with the gel so as to be activated under the presence of light or heat. A conductive circuit and a resistor define poles of the electrodes on the container of the conductive gel and the part of the body. The photosensitive bleaching product is activated by applying photonic energy of a wavelength of 400 to 500 nanometers.

A load driver includes a switching element connected to a load, a constant current generator that generates a constant current, and a driver circuit that turns on the switching element for an on-period, which depends on a value of the constant current and is shortened with an increase in the value of the constant current. The constant current generator supplies a first constant current having a first current value to the driver circuit during the on-period, and supplies a second constant current having a second current value smaller than the first current value after the on-period has elapsed and the switching element reaches an on state.