43results about How to "Current change" patented technology

An illumination device and methods are provided herein for avoiding over-current and over-power conditions in one or more power converters included within the illumination device. The illumination device may include at least a plurality of light emitting diode (LED) chains, a driver circuit, at least one power converter, and a control circuit. In some embodiments, the control circuit may be generally configured for determining a maximum safe current level and / or a maximum safe power level attributed to the power converter(s) at a present operating temperature, and for adjusting respective drive currents supplied to the plurality of LED chains by the driver circuit, so as not to exceed the maximum safe current level or the maximum safe power level at the present operating temperature. In some embodiments, a temperature sensor may be included within the illumination device for measuring the operating temperature presently associated with the power converter(s).

A semiconductor device may include a coding lookup table unit including a plurality of coding lookup tables each of which is selected by a respectively selection signal, and a selection unit configured to receive one of N-bit parallel data and extract respective encoded data corresponding to the selection signal and to which the N-bit parallel data is mapped from the coding lookup table unit, and encoded data and extract respective N-bit parallel data corresponding to the selection signal and to which the encoded data is mapped from the coding lookup table unit, wherein N is 2 or an integer greater than 2, and wherein the coding lookup tables respectively store a plurality of coded data patterns that respectively correspond to patterns of the N-bit parallel data and are random temporally and spatially.

In the motor drive apparatus, a Hall element outputs a first sinusoidal signal and a second sinusoidal signal, of mutually opposite phases, in accordance with rotor position. A hysteresis comparator compares the first sinusoidal signal and the second sinusoidal signal outputted from the Hall element, and outputs a rectangular wave signal. A pulse width modulation signal generation circuit detects timing at which phase switches, based on the first sinusoidal signal and the second sinusoidal signal outputted from the Hall element, and outputs a pulse width modulation signal in which duty ratio gradually changes, in a predetermined time-period in which the phase switches. A drive circuit combines the rectangular wave signal and the pulse width modulation signal by a logical operation, and drives the fan motor.

In the motor drive apparatus, a Hall element outputs a first sinusoidal signal and a second sinusoidal signal, of mutually opposite phases, in accordance with rotor position. A hysteresis comparator compares the first sinusoidal signal and the second sinusoidal signal outputted from the Hall element, and outputs a rectangular wave signal. A pulse width modulation signal generation circuit detects timing at which phase switches, based on the first sinusoidal signal and the second sinusoidal signal outputted from the Hall element, and outputs a pulse width modulation signal in which duty ratio gradually changes, in a predetermined time-period in which the phase switches. A drive circuit combines the rectangular wave signal and the pulse width modulation signal by a logical operation, and drives the fan motor.

The invention provides a non-adiabatic transferring device of a cold atomic group and a method thereof. The non-adiabatic transferring device comprises a vacuum cavity with an atomic source, two pairs of inverse Helmholtz coils, a bias magnetic field coil group, a vacuum pump system, an optical system, a coil current control system based on LabVIEW, and a CCD (Charge Coupled Device) detection system. A magnetic quadrupole trap for transferring the cold atomic group is generated by the two pairs of the inverse Helmholtz coils; and a speed of the center position of the magnetic quadrupole trap at is controlled by changing coil current. According to the non-adiabatic transferring device provided by the invention, a transferring speed of the magnetic quadrupole trap is modulated by modulating the coil current for generating the magnetic quadrupole trap, thereby avoiding the heating effect on the cold atomic group and the excitation of a mass center motion of the cold atomic group. The non-adiabatic transferring device provided by the invention has the characteristics of rapid transferring speed, small energy consumption and no damages on electronic devices.

A controller of a multi-phase electric motor has a drive section having an upper arm switching element and a lower arm switching element for driving the multi-phase electric motor, a single current detection section for detecting a current value of the multi-phase electric motor, a pulse width modulation signal generation section for generating plural pulse width modulation of each phase within one control period based on the current value detected by the current detection section and a carrier signal, and a phase movement section for moving the pulse width modulation signal of a predetermined phase generated by the pulse width modulation signal generation section by gradually changing a movement amount of the phase in one control period, and outputting the resultant pulse width modulation signal to the drive section.

In the motor drive apparatus, a Hall element outputs a first sinusoidal signal and a second sinusoidal signal, of mutually opposite phases, in accordance with rotor position. A hysteresis comparator compares the first sinusoidal signal and the second sinusoidal signal outputted from the Hall element, and outputs a rectangular wave signal. A pulse width modulation signal generation circuit detects timing at which phase switches, based on the first sinusoidal signal and the second sinusoidal signal outputted from the Hall element, and outputs a pulse width modulation signal in which duty ratio gradually changes, in a predetermined time-period in which the phase switches. A drive circuit combines the rectangular wave signal and the pulse width modulation signal by a logical operation, and drives the fan motor.

A unit HBT and a unit FET are arranged to be adjacent to each other through an isolation region and a base electrode of the unit HBT is connected to a source electrode of the unit FET to form a unit element, and a plurality of unit elements are connected to form an active element. This makes it possible to implement the active element in which a current is not likely to concentrate on the unit element and no destruction is generated by the second breakdown. Moreover, although a buried gate electrode structure is used to ensure a withstand pressure in the unit FET, a buried portion is structured not to be diffused to an InGaP layer, and thereby it is possible to prevent Pt from being abnormally diffused. Furthermore, a selection etching can be used for a formation of an emitter mesa, that of a base mesa, that of a ledge in the unit HBT, and a gate recess etching in the unit FET, and a good reproducibility can be obtained.

The method of converting high voltage AC lines into bipolar high voltage DC systems makes use of the three transmission lines (referred to as the positive pole, the negative pole, and the modulating pole) in an existing high voltage AC system as transmission lines in a bipolar high voltage DC system. When current from the power source is up to the thermal current limit of the transmission lines, the transmission lines operate in two-wire mode, where current is delivered in the positive pole and returned in the negative pole, the modulating pole being open. When power source current exceeds the thermal current limit, operation is in three-wire mode, alternating for predetermined periods between parallel configuration of the positive pole and the modulating pole to divide current for delivery to the load, and parallel configuration of the negative pole and the modulating pole, dividing the return current.

An automatic toroidal core winding machine, including: a frame, control device, clamping and wire arranging mechanism, winding mechanism, wire delivering mechanism, feeding mechanism, automatic stripping mechanism and wire reclaiming device for reclaiming excessive wires around the shuttle, the winding mechanism including a shuttle and driving device for supporting and driving the shuttle to rotate, the shuttle includes a slider and wire storage and hooking aperture, and the frame includes a detecting and positioning mechanism used for positioning the ring opening, the slider and the wire storage and hooking aperture of the shuttle, and a wire hanging device for hanging the wire allowing the shuttle to store and wind the wire. The machine achieves automation from wire delivery, feeding, shuttle opening to wire hanging, wire winding, wire cutting, product taking and wire reclaiming with significantly improved production efficiency, reduced restriction and effect on the quality of winding from manual proficiency.

A mobile wireless communications device includes a housing and circuit board in the housing and having radio frequency (RF) circuitry and a power amplifier and microphone mounted thereon. An antenna is carried within the housing and operative with the RF circuitry. An RF shield surrounds and isolates the microphone from the RF circuitry, power amplifier and antenna and shields the microphone from radiated energy generated from the RF circuitry, antenna or power amplifier.

In an IC card in which an internal circuit is operated by an internal power supply formed from alternate current from outside received by an antenna, the voltage of the internal power supply sometimes changes due to the operation of the internal circuit. Therefore, the voltage controlling circuit of the present invention includes a voltage controlling current source, and when the internal circuit is not operated and the current higher than a predetermined current is detected in the voltage controlling current source, an operating current detector circuit outputs an enable signal. When the internal circuit is operated in response to the enable signal, the current consumed in the internal circuit is subtracted from the current passing through the voltage controlling current source. Consequently, the current change in the entire internal power supply can be prevented, and the output voltage of the internal power supply can be kept constant.

A structure comprising a charge pump and a charge pump current controller electrically coupled together, and a method for operating the structure. The charge pump comprises a sourcing current control gate on the charge pump's sourcing current path, and a sinking current control gate on the charge pump's sinking current path. The longer the two inputs of the charge pump are at the opposite levels, the more the charge pump current controller causes the sourcing and sinking current control gates to increase the sourcing and sinking currents flowing through the sourcing and sinking current paths, respectively.

A current generator circuit included in a triangle-wave generator circuit in a control circuit includes plural stages of current mirrors connected in parallel with each other. The plural stages of current mirrors are placed so that the sum of output currents output therefrom becomes an output current of the current generator circuit. A switching element that controls the on / off state of a current in accordance with the amount of load current of a DCDC converter is connected to each of the current mirrors.

A laser transmitter within an optical transceiver includes a heating element. The heating element is coup led to the laser package and is controlled to allow the laser to be heated to a higher temperature than the ambient temperature when low environmental temperature extremes occur. The transmitter includes a semiconductor laser having an optimal operational temperature range, a laser driver circuit coupled to the laser that provides a modulation current and a bias current to drive the laser, a heating element thermally coupled to the laser and a heating control circuit that monitors the bias current applied to the laser for drops in bias current that are indicative of drops in the surrounding ambient temperature. In response to a drop in bias current, the control circuitry energizes the heating element to provide heat to the laser.

In an IC card in which an internal circuit is operated by an internal power supply formed from alternate current from outside received by an antenna, the voltage of the internal power supply sometimes changes due to the operation of the internal circuit. Therefore, the voltage controlling circuit of the present invention includes a voltage controlling current source, and when the internal circuit is not operated and the current higher than a predetermined current is detected in the voltage controlling current source, an operating current detector circuit outputs an enable signal. When the internal circuit is operated in response to the enable signal, the current consumed in the internal circuit is subtracted from the current passing through the voltage controlling current source. Consequently, the current change in the entire internal power supply can be prevented, and the output voltage of the internal power supply can be kept constant.

A display device includes: pixels each including a light emitting element; scan lines, signal lines, and power supply lines; a scan line drive circuit applying a selection pulse to the scan lines in succession; a signal line drive circuit applying a signal pulse to the signal lines through switching a gray-scale interpolation voltage, a basic voltage and a video signal voltage, in this order to perform gray-scale interpolation; and a power supply line drive circuit applying a control pulse to the power supply lines. The scan line drive circuit generates the selection pulse through alternately switching an on-voltage and an off-voltage, and applies the pulse to the scan lines so that application of the on-voltage to the scan line starts in a time period of the gray-scale interpolation voltage and the on-voltage is switched to the off-voltage in a time period of the basic voltage.

The invention discloses a direct-current submarine cable for flexible power transmission. The direct-current submarine cable is characterized by comprising two direct-current units, a liner layer is lapped outside the two direct-current units, filling strips are filled in gaps formed by the liner layer and the direct-current units, at least one flat armor layer is arranged outside the liner layer, and an outer wrapping layer is lapped outside at least one flat armor layer. Each of the direct-current units comprises a water blocking conductor, an inner shielding layer, an insulating layer and an outer shielding layer which are arranged successively from the inside to the outside. Semi-conductive water blocking tapes are lapped outside the outer shielding layers, lead sheaths and protection sheaths are arranged outside the semi-conductive water blocking tapes successively, the insulating layers are made of direct-current crosslinked polyethylene, and the inner shielding layers and the outer shielding layers are made of direct-current shielding materials. The direct-current submarine cable has the advantages that the direct-current units are used, so that the submarine cable is high in transmission efficiency and small in line loss, long-distance large-capacity power transmission is facilitated, the current can be adjusted easily, the power transmission direction can be changed easily, and the stability is high; and the direct-current submarine cable has a longer service life than that of an alternating-current submarine cable.

A pulse width modulation control unit multiplies a value of a user side setting signal by a value of a dimming signal to obtain a pulse width modulation output current control signal. The pulse width modulation control unit sends the pulse width modulation output current control signal to a light emitting diode driving unit. The light emitting diode driving unit multiplies a value of the pulse width modulation output current control signal by a value of a maximum output current of the light emitting diode driving unit to obtain a light emitting diode pulse width modulation driving current. The light emitting diode driving unit drives a light emitting diode by the light emitting diode pulse width modulation driving current.

In an electric tool, in order to carry out a phase control or an antiphase control using a transistor with the cost lower and structure simpler, and to suppress an electromagnetic noise, constant voltage generating means of the electric tool includes a series circuit of a resistor 91 and a diode 93 and a parallel circuit of a capacitor 95 and a Zener diode 97, one end of the resistor 91 is connected to a node between an AC power supply 1 and an AC motor 3, a cathode of the diode 93 is connected to one end of the capacitor 95 and a cathode of the Zener diode 97, and the other end of the capacitor 95 and an anode of the Zener diode 97 are connected to sources of transistors 51, 52. One ends of resistors 53, 54 are connected to gates of the transistor 51, 52, and a voltage at the other ends of the resistor 53, 54 are switched between a voltage at a node between the series circuit and the parallel circuit and a voltage of the source of the transistors 51, 52 so that the transistors 51, 52 are turned ON or OFF.

The invention provides a device for measuring stress and strain among sand particles and a detection method. The device comprises a protective shell with a spherical appearance structure, wherein theprotective shell is provided with a plurality of draw hooks; a film-shaped central interlayer is arranged on the inner wall of the protective shell; an inner layer is adhered to the inner wall of thecentral interlayer; and a measurement sensing element, a signal acquisition and transmission system, a storage element, a power supply element and a data processing and analysis element are integratedin a cavity of the protective shell. The device and the method can be used for monitoring the stress and strain inside coral sand in real time, and the safety in island engineering construction is ensured.

Method for Controlling Electrodes for Bio-impedance Measurements and Apparatus for Bio-impedance Measurements There is provided a control circuit for electrodes in a bio-impedance measurement system, the bio-impedance measurement system comprising screening current injecting electrodes and measuring current injecting electrodes, the control circuit comprising: a current generator for connection to at least one screening current injecting electrode; and an measuring signal output configured to establish a measuring potential between the measuring current injecting electrodes, wherein the control circuit is configured such that the measuring potential is dependent on a measure of a potential difference resulting from the screening current. The control circuit uses the value of the potential resulting from the screening current to determine the potential difference between the measuring current injecting electrodes. In this way the flow of measuring current can be made smaller than the screening current and necessarily at a safe level.

A gas detector includes a measurement control section that controls a voltage application section, obtains an output current flowing between a first electrode and a second electrode of an electrochemical cell, and detects a concentration of sulfur oxides in exhaust gas based on the output current. The measurement control section uses a minimum value of the output current obtained by using a current detection section in a period in which lowering sweep is executed and in which an applied voltage is a voltage within a detection voltage range that is equal to or lower than a decomposition initiation voltage of sulfur oxides as a parameter used for detection of the concentration of sulfur oxides.

A current generator circuit included in a triangle-wave generator circuit in a control circuit includes plural stages of current mirrors connected in parallel with each other. The plural stages of current mirrors are placed so that the sum of output currents output therefrom becomes an output current of the current generator circuit. A switching element that controls the on / off state of a current in accordance with the amount of load current of a DCDC converter is connected to each of the current mirrors.

A unit HBT and a unit FET are arranged to be adjacent to each other through an isolation region and a base electrode of the unit HBT is connected to a source electrode of the unit FET to form a unit element, and a plurality of unit elements are connected to form an active element. This makes it possible to implement the active element in which a current is not likely to concentrate on the unit element and no destruction is generated by the second breakdown. Moreover, although a buried gate electrode structure is used to ensure a withstand pressure in the unit FET, a buried portion is structured not to be diffused to an InGaP layer, and thereby it is possible to prevent Pt from being abnormally diffused. Furthermore, a selection etching can be used for a formation of an emitter mesa, that of a base mesa, that of a ledge in the unit HBT, and a gate recess etching in the unit FET, and a good reproducibility can be obtained.

A dielectric film layer structure and a fabricating method thereof are provided. The dielectric film layer structure at least has a first capacitor electrode, a dielectric layer, and a second capacitor electrode, wherein the dielectric layer includes two materials of SiNx and SiOx. In a place where voltage drop is relatively large, the dielectric layer is mainly made of SiNx, and in a place where the voltage drop is relatively small, the dielectric layer is mainly made of SiOx, thereby changing current for charging thin film transistors, reducing influence of the voltage drop, and improving uniformity of panel voltage output.

The invention relates to an annular excitation power generator structure, which comprises: an annular track; at least one magnetic block positioned on the annular track and capable of forming a movingtrack with a closed path in the annular track; at least one input coil, wherein each input coil surrounds a part of the annular track; at least one pulse wave generator connected with a correspondinginput coil; and at least one output coil, wherein each output coil surrounds a part of the annular track and is not in contact with the input coil, and the annular track penetrates through the interiors of the input coils and the output coils. According to the invention, when the pulse wave generator inputs pulse waves to the input coil, the pulse waves generate an excitation effect on the inputcoil, so that a magnetic field is generated in the input coil to drive the magnetic block to move; and when the magnetic block moves on the annular track and passes through the output coil, the outputcoil generates induced current and outputs the induced current outwards, so that the purpose of power generation is achieved.