5485 results about "Current source" patented technology

Aspects of transcranial magnetic stimulation (TMS) devices are described. In one example, the TMS device includes a magnetic flux shutter that includes a multi-turn coil and a magnetic film. The magnetic film extends in a loop to encircle a region, and the multi-turn coil is continuously wound around the magnetic film. The TMS device also includes a magnet that is positioned in the region within a boundary of the magnetic film, with the magnet generating a magnetic flux. The TMS device also includes a current source coupled to the multi-turn coil. The current source is configured to deliver a current to the multi-turn coil, to vary a permeability of the magnetic film and a density of the magnetic flux extending outside the region of the magnetic flux shutter during operation.

The invention provides a flexible electronic device multi-physics field coupling performance simulation analysis method, and relates to the technical field of flexible electronics. Firstly, a geometric model of the flexible electronic device is constructed; the geometric model comprises a three-layer assembly structure of an electronic chip, an adhesive layer and a flexible PCB layer, and an interconnection structure; setting electromagnetic-thermal-mechanical field coupling parameters of the geometric model; then, grid division is conducted on the geometric model through a finite element method, and the grid division precision of the area where the interconnection structure is located is higher than that of other areas; building a multi-physics field coupling model according to the geometric model and set coupling parameters; applying load and boundary conditions to the model, wherein the load and boundary conditions comprise a current source, a heat generation load, a convection heat dissipation boundary condition and a mechanical constraint condition; and simulating the working state of the flexible electronic device under the action of multi-physics field coupling in the multi-physics field coupling model to obtain a simulation result. According to the method, the performance and the failure mechanism of the flexible electronic device under the multi-physics field coupling effect can be effectively predicted.

The invention discloses a SiC MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) driving circuit and a control method thereof, the SiC MOSFET driving circuit comprises an active current source driving circuit, a SiC MOSFET, a load current detection circuit, a drain-source inter-electrode voltage overshoot detection circuit, an analog-to-digital conversion module and an FPGA (Field Programmable Gate Array) module, and a self-adaptive adjustment algorithm is built in the FPGA module. The load current detection circuit and the drain-source inter-electrode voltage overshoot detection circuit have low requirements for real-time performance, use of high-speed simulation devices is avoided, hardware design cost is reduced, a self-adaptive adjustment algorithm can adjust SiC MOSFET gate drive parameters in real time according to output of the load current detection circuit and the drain-source inter-electrode voltage overshoot detection circuit, and the self-adaptive adjustment algorithm can adjust the gate drive parameters of the SiC MOSFET in real time according to the output of the drain-source inter-electrode voltage overshoot detection circuit. Therefore, overshoot and switching loss are self-adaptively balanced, and safe operation of the SiC MOSFET is ensured. The technical problems that a SiC MOSFET driving circuit driven by an active grid is high in hardware cost and is difficult to balance voltage and current overshoot and switching loss are solved.

The invention discloses an E-mode device nonlinear current model parameter extraction method considering a gate current effect, and relates to the technical field of enhanced device modeling. Comprising the following steps: establishing a nonlinear current model of an E-mode device; extracting parasitic resistance of the transistor; removing the influence of parasitic resistance of the transistor, and calculating gate-source and gate-drain node voltages of an intrinsic region in the nonlinear current model to obtain an intrinsic gate-source voltage and an intrinsic drain-source voltage; extracting intrinsic gate current model parameters; obtaining the drain-source current component of the intrinsic part from the influence of the fused gate current component in the actually measured drain-source current of the transistor; extracting intrinsic nonlinear drain-source current model parameters; and substituting the intrinsic nonlinear drain-source current model parameter value into an intrinsic nonlinear drain-source current model equation for verification. According to the method, gate current component calculation is introduced into a traditional nonlinear current model parameter extraction method, and accurate extraction of intrinsic nonlinear current source parameters is achieved.

The invention relates to the technical field of field data acquisition, in particular to an on-line temperature self-compensation calibration method and circuit for a force measurement transmitter. The calibration method comprises the steps that a working strain gauge and a temperature compensation gauge are synchronously excited through a two-way precision constant current source, the working strain gauge and the temperature compensation gauge are consistent in material parameter and are located in the same temperature field, and output current values of the two-way precision constant current source are equal and are controlled by a high-precision reference voltage source and a sampling resistor in a closed-loop mode. According to the invention, differential signals of the working strain gauge and the temperature compensation gauge are decoupled in real time through double-path precise constant-current source excitation and synchronous ADC acquisition technologies, gradient compensation is carried out on the temperature change rate in combination with a dynamic weighting algorithm, a lag error of traditional fixed coefficient compensation in a transient temperature field is effectively eliminated, and the accuracy of temperature compensation is improved. And online self-compensation of the temperature drift of the strain gauge is realized.

An electrical circuit includes positive and negative voltage rails, a reference voltage rail, a non-trimmable bandgap core configured to output a voltage reference on the reference voltage rail, and a trimming element in an auxiliary section located external to the bandgap core. A current source is coupled to the non-trimmable bandgap core and the positive voltage rail. An auxiliary diode arranged in an auxiliary section outside of the bandgap core is coupled to the current source and negative voltage rail. The trimming element is coupled to the current source external to the non-trimmable bandgap core and has an adjustable set point. The adjustable set point is adjusted to inject a corresponding bias current to the auxiliary section during a trimming process and thereby change the voltage reference.

The present invention discloses a prediction method for a crosstalk spike in a half bridge of current-source inverter with silicon carbide devices, where, the prediction method includes calculation of the crosstalk voltage spike in the circuit of current-source type double-pulse test and analysis of the effect of each parameter on the magnitude of the crosstalk spike. The prediction method of the present invention analyzes the horizontal conduction crosstalk mechanism between the gate-source junction of the MOSFET caused by the high-frequency switching action of the silicon carbide (SiC) MOSFET and the SiC Schottky diode connected in series, and derives the prediction model for the crosstalk voltage spike in the half-bridge of current-source inverter. Based on the equivalent circuit of the current-source-type double-pulse test and the crosstalk-induced mechanism, the extreme value of crosstalk voltage spike is accurately predicted, which is helpful to analyze the effects of the drive circuit and the parameters of the power circuit on the crosstalk voltage spike through the prediction model.

The invention discloses a memristor-based signal detection circuit and method, a receiver and equipment, and relates to the field of wireless communication, a voltage source module of the circuit is connected with a voltage input end of a memristor array module, and a current source module is connected with a current input end of the memristor array module; the current output end of the memristor array module is connected with the reverse input end of the operational amplifier module and one end of the feedback resistor module, the other end of the feedback resistor module and the output end of the operational amplifier module are connected with the input end of the multiplier module, and the output end of the multiplier module is connected with one end of the resistor module. The voltage of the voltage source module is set according to the emission vector set; the current of the current source module is set according to the received radio frequency signal, and the conductance value of the memristor is set according to the channel matrix, so that a relatively low bit error rate of signal detection can be realized on the basis of greatly reducing calculation time and power consumption, and meanwhile, the requirement on programmable bit precision of the memristor is also reduced.

The present disclosure provides an orbitronic device having orbital Hall effect or inverse orbital Hall effect, and method for enhancing the efficiency thereof. The orbital torque device comprises: a ferromagnetic / non-magnetic heterojunction formed by compounding a ferromagnetic layer and a non-magnetic layer as an orbital current source, wherein the ferromagnetic layer contains a ferromagnetic material, the non-magnetic layer contains a non-magnetic material with weak spin-orbit coupling, the non-magnetic layer is used as an orbital Hall channel to generate orbital current, and the orbital current enters the ferromagnetic layer, so that an orbital torque is generated through an orbital-spin conversion effect of the ferromagnetic layer to realize switching of a magnetic moment. The present disclosure can provide orbitronic device with low cost and good performance.

A circuit device includes a current source circuit, a first charging circuit that supplies a first charging current to a charging node, a second charging circuit that supplies a second charging current to the charging node, and a control circuit that sets a current value of the first charging current and the second charging current, based on a current setting value. When the current setting value is in a first range, the first charging circuit supplies the first charging current. When the current setting value is in a second range on a higher current side, the second charging circuit supplies the second charging current. At switching between the first range and the second range, the first charging circuit supplies the first charging current and the second charging circuit supplies the second charging current.

A turn-on circuit is configured to supply a current as a source to the gate of a high-side transistor. A first current source supplies an output current that is switchable between a first current amount and a second current amount that is smaller than the first current amount. A first switch is coupled between a first output node of a first current mirror circuit and the gate of the high-side transistor. A second current source generates a second current. A second switch is coupled between a first output node of a second current mirror circuit and the gate of the high-side transistor.

The invention discloses a Fourier transform and S transform combined battery impedance spectroscopy measurement method and device, and aims to improve the precision, speed and reliability of impedance measurement of a battery energy storage system. According to the method, a multi-frequency component excitation signal is generated through a controllable current source, and current and voltage response signals of a battery are synchronously acquired and are respectively input into a Fourier transform module and an S transform module for frequency domain analysis. The Fourier transform module extracts impedance spectrums of low and medium frequency bands, and the S transform module extracts impedance spectrums of medium and high frequency bands through Gaussian window time-frequency analysis. And a data fusion algorithm is adopted to perform composite processing on results of the two modules, including a direct selection method, an arithmetic average method, an amplitude and phase calibration method and a weighted average method, so that smooth transition and optimization between frequency bands are realized, and finally the electrochemical impedance spectrum is generated. Through collaborative analysis of Fourier transform and S transform, parameter optimization and a fusion algorithm, the efficiency and accuracy of impedance spectroscopy measurement are remarkably improved, and the method is suitable for rapid monitoring and diagnosis of the battery state.

A method of resolving a number of photons received by a photon detector includes optically coupling a waveguide to a superconducting wire having alternating narrow and wide portions; electrically coupling the superconducting wire to a current source; and electrically coupling an electrical contact in parallel with the superconducting wire. The electrical contact has a resistance less than a resistance of the superconducting wire while at least one narrow portion of the superconducting wire is in a non-superconducting state. The method includes providing to the superconducting wire, from the current source, a current configured to maintain the superconducting wire in a superconducting state in the absence of incident photons; receiving one or more photons via the waveguide; measuring an electrical property of the superconducting wire, proportional to a number of photons incident on the superconducting wire; and determining the number of received photons based on the electrical property.

A control method of a high gain image sensor is provided. A column bias current source and a column PMOS amplifier transistor are provided in a column signal readout unit, the column bias current source is connected to a column-common current output connecting line, a drain of the column PMOS amplifier transistor is connected to a column-common current input connecting line, and a gate of the column PMOS amplifier transistor is connected to the column-common current output connecting line, to acquire an amplified signal of a floating diffusion region of a readout row pixel unit on the column-common current input connecting line. An SHCG is achieved, and a dynamic range in a dark light scene is expanded. A device structure size in the column signal readout unit can be much larger than the transistor in the pixel, which results in better process consistency and more flexible adjustment of the conversion gain.

The invention provides a control method of a high-gain image sensor, which is characterized in that a column bias current source and a column PMOS (P-channel Metal Oxide Semiconductor) amplifier tube are arranged in a column signal reading unit, the column bias current source is connected with a current output connecting line shared by a column, and a drain electrode of the column PMOS amplifier tube is connected with a current input connecting line shared by the column; the grid electrode of the column PMOS amplifier tube is connected with the common current output connecting line of the column directly or through a capacitor, and an amplified signal of a floating diffusion region of a read-out pixel unit can be obtained on the common current input connecting line of the column, so that the ultrahigh conversion gain is realized, and the dynamic range in a dark light scene is expanded; the size of a device structure in the column signal reading unit can be far larger than that of a transistor in a pixel, the process consistency is better, and the conversion gain can be adjusted more flexibly; the switching between the SHCG mode and the STD mode is realized by driving the switch module in the column signal reading unit, the impact on a power supply and the ground is smaller during operation, and the circuit stability is improved.

Wireless circuitry is provided that includes a transformer having a primary coil and a secondary coil, a first group of switchable capacitors coupled to a first terminal of the primary coil, a second group of switchable capacitors coupled to a second terminal of the primary coil, and capacitance measurement circuitry selectively coupled to a center tap of the primary coil during a measurement mode. The capacitance measurement circuitry can include a current source, a current sink, a comparator, a voltage generator for providing one or more threshold / reference voltages to the comparator, a frequency measurement circuit, and a capacitance calculation circuit configured to compute a capacitance of the first and second groups of switchable capacitors.

Provided is a method for preparing a collagen membrane for guided tissue regeneration. By utilizing the electrochemical deposition technology and using collagen as the starting material, the method achieves the electrochemical deposition in a low-temperature environment using a direct-current source, and thus, in a constant-voltage output mode, prepares a collagen membrane of an asymmetric structure (with one dense surface and one loose and porous surface) in one step at a high voltage. Also, by means of asymmetric cross-linking, the membrane may be asymmetrically degraded in vivo, thus promoting the rapid repair of a wound while keeping a stable shielding effect on the wound. The method features ease to operate, efficiency, environment conservation, and good scalability. The obtained collagen membrane possesses excellent mechanical properties and uniform overall performance. The area of the collagen membrane of the asymmetric structure prepared by the preparation method is equal to that of the electrode plate, such that scale-up production can be achieved by using an electrode plate with a greater area, thereby improving productivity.

A control device (100) for controlling a number N, with N ≥ 1, of actuators (200) for actuating N optical elements of an optical system, comprising a control node (K2) coupling to the actuator (200) for providing a control voltage (V2) for the actuator (200), an amplifier (110) configured to receive a supply voltage (V1) provided at an input node (K1) and to provide an output voltage (V3) at an output node (K3), wherein the amplifier (110) comprises a plurality M, with M ≥ 2, of current sources (111, 112) comprising at least one charge-controlled current source (112) and a holding capacitor (113) for maintaining the level of the provided output voltage (V3), and a buffer coupled between the output node (K3) and the control node (K2). (120), which is designed to,to decouple the control node (K2) from the output node (K3) and to provide the control voltage (V2) for the actuator (200) based on the level of the output voltage (V3) of the holding capacitor (113).

The invention discloses a display backboard and a display device. The display backboard comprises sub-pixel units and a mirror current source module, each sub-pixel unit comprises a pixel driving circuit with an adjusting module and a light-emitting device, the mirror current source module is electrically connected with the adjusting modules in the pixel driving circuits, and the mirror current source module is used for adjusting adjusting current input to the adjusting modules. The adjusting currents input to the sub-pixel units with different colors by the mirror current source module are different; according to the invention, the mirror current source module connected with the adjusting module in the pixel driving circuit is arranged in the display backboard to adjust the adjusting current input to the sub-pixel units with different colors, so that the sub-pixel units with different colors drive the light emitting device to emit light with different driving currents. In this way, the light-emitting devices of different colors have preset light-emitting luminous flux, regulation and control of different gray scales are achieved in combination with a digital subfield scanning method, and full-color display of the display backboard is achieved under the existing clock frequency.

The invention discloses a rapid discharge circuit suitable for a high-voltage LDO and a discharge method thereof, the rapid discharge circuit comprises a PMOS tube M1, a PMOS tube M2, a PMOS tube M3, an NMOS tube M4, an NMOS tube M5, an NMOS tube M6, an NMOS tube M7, a current source I0 and a Zener diode Z2, the source electrodes of the PMOS tubes M1, M2 and M3 are connected with an input power supply Vin, the PMOS tubes M1, M2 and M3 form a current mirror, the drain electrode of the NMOS tube M4 and the NMOS tube M6 form a current mirror, an input signal EN controls the NMOS tube M7, and the Zener diode Z2 limits the grid voltage of the NMOS tube M5. According to the high-voltage LDO, the function of rapidly discharging the output signal Vout in the turn-off state of the high-voltage LDO can be achieved through a small turn-off current and a simple circuit structure.

Provided in the present application are a band-gap reference current source, a low dropout regulator and a power manager, which are applied to the technical field of power chips. The band-gap reference current source uses dual band-gap references to form a band-gap reference loop, and uses an operational amplifier clamping unit to implement clamping adjustment, so as to generate a reference current that is in direct proportion to the temperature, which is conducive to using the reference current to perform linear voltage stabilization subsequently, such that the regulator has a relatively high loading capacity, a very low quiescent current and a relatively high power noise suppression ratio, thereby improving the overall efficiency of a voltage-stabilizing circuit, and also greatly reducing the layout area.

An output driver includes a pull-up transistor having a first current path coupled between a supply voltage and an output node; a pull-down transistor having a second current path coupled between the output node and a reference ground; the gate driving circuit is used for driving the control end of the pull-up transistor according to the first control signal and driving the control end of the pull-down transistor according to the second control signal; the logic control circuit is used for generating a first control signal and a second control signal according to an input signal and an enable control signal; and the current source circuit is used for respectively providing pull-down or pull-up current related to the power supply voltage to the control end of the pull-up transistor or the pull-down transistor when the output signal at the output node is in a rising edge or falling edge process, so as to counteract the influence of the power supply voltage on the transmission time of the output signal. Therefore, stable transmission time can be maintained in a wide power supply voltage range.

The invention discloses a low-phase noise ring voltage-controlled oscillator based on multiphase injection locking, relates to the technical field of integrated circuits, and is used for solving the technical problems that an existing injection locking oscillator limits the frequency tuning range and cannot effectively suppress noise. The invention discloses a low-phase noise ring voltage-controlled oscillator based on multiphase injection locking. The low-phase noise ring voltage-controlled oscillator comprises a first ring oscillator unit and a second ring oscillator unit, the n first ring oscillator units are connected in series to form a chain structure; the second ring oscillator unit is provided with a cross coupling inverter complementary injection unit and a tail current source injection unit; a first output end of the chain structure is connected with a second input end of the second ring oscillator unit, and a second output end of the chain structure is connected with a first input end of the second ring oscillator unit; a first signal is injected into a cross-coupling inverter complementary injection unit and a tail current source injection unit, and a second ring oscillator unit receives a second signal output by a chain structure and then outputs a third signal.

The invention discloses an electro-magnetic doubly salient motor torque ripple suppression method based on harmonic double closed-loop control, and the method comprises the steps: constructing the harmonic double closed-loop control of a torque ripple outer ring and a current harmonic inner ring in an electro-magnetic doubly salient motor current source type drive system of a multiplexing excitation winding; a torque pulsation outer ring observes electromagnetic torque through a model reference adaptive method, pulsation components of the torque pulsation outer ring are extracted in combination with an adaptive notch filter, and a current harmonic inner ring given value is output through closed-loop regulation; the current harmonic inner ring extracts harmonic current by constructing a harmonic space decoupling transformation matrix and combining with a rotating coordinate system of corresponding subharmonics, current harmonics counteracting torque pulsation of the electro-magnetic doubly salient motor are generated through closed-loop adjustment, and the output characteristic of the motor is improved. According to the method provided by the invention, the torque ripple amplitude can be suppressed in a closed-loop manner, the given value of the harmonic current can be automatically adjusted, specific current harmonic injection is realized, the output torque ripple of the electro-magnetic doubly salient motor is eliminated, and the problems that a traditional harmonic injection method is not matched under different operation conditions of the motor and depends on motor parameters are solved.

The embodiment of the utility model provides a resistor calibration circuit, a resistor calibration device and an electronic device. The resistor calibration circuit comprises a current source module used for outputting a reference current; the standard resistor module is connected with the current source module to receive the reference current and generate a reference voltage; in the working process of the resistor calibration circuit, a resistor to be calibrated is connected with the current source module to receive the reference current and generate a voltage to be measured, and the analog-to-digital converter is connected with the standard resistor module to perform analog-to-digital conversion on the voltage to be measured based on the reference voltage. According to the resistance calibration circuit, the analog-to-digital converter in the module to be measured is multiplexed for resistance calibration, an additional high-precision measurement calibration system is not needed, and the resistance can be calibrated only by providing the current source module and the standard resistance module, so that the resistance calibration cost is reduced.

The invention discloses a frequency control type wide-range variable quiescent current source and a CT-sigma delta modulator, the frequency control type wide-range variable quiescent current source comprises a frequency control type bias generation circuit and a current mirror circuit, the frequency control type bias generation circuit comprises at least one capacitor bias diode circuit, and the current mirror circuit comprises at least one capacitor bias diode circuit. The bias circuit is used for generating bias voltage. The current mirror circuit is used for copying current flowing through a diode load in the capacitor bias diode circuit according to the bias voltage, and the current linearly changes along with the clock frequency. The frequency control type wide-range variable quiescent current source is simple in circuit, the scaling range of the generated variable quiescent current is large, control is easy and convenient, linear scaling of the CT-sigma delta modulator system power consumption along with the sampling frequency is achieved, and the high energy efficiency of the system under different sampling frequencies is guaranteed.

The invention provides a device and method for testing the reliability of a power sensor, and the device comprises a magnetic field generation unit which is used for providing an alternating current for a Helmholtz coil through a power frequency current source, and generating a controllable magnetic field; the electric field generating unit is used for providing a high-voltage direct current or power frequency alternating current power supply for the parallel-plate capacitor through a high-voltage generator to generate a uniform electric field; the tested unit is used for providing a standard excitation signal through a standard source matched with the to-be-tested sensor, simulating an input condition of the to-be-tested sensor under an actual working condition and collecting output data of the to-be-tested sensor; and the control unit is used for setting test parameters, generating a control instruction according to the test parameters and generating a test result according to the output data. According to the device and the method, by simulating a strong magnetic field and a strong electric field environment and combining application of various measured parameters and an automatic control system, the reliability evaluation requirement of the sensor under the actual working condition is fully met.

An image sensor may include an array of imaging pixels arranged in rows and columns. Each column of pixels can be coupled to a column analog-to-digital converter (ADC) via a pixel output line. The column ADC can include a first low noise single-ended comparison stage, a second low noise single-ended comparison stage, a latch circuit, and a counter. The first low noise single-ended comparison stage may include one or more current source transistors, a voltage ramp generator, a common source amplifier transistor, one or more autozero components, one or more capacitors such as a noise filtering capacitor, and a voltage clamping circuit. The voltage ramp generator can output an increasing voltage ramp or a decreasing voltage ramp.

The invention discloses an active damping control system for improving the output impedance of a current source type inverter, which comprises a current loop control loop, an active damping branch and an improved phase-locked loop, and is characterized in that the difference value of reference current and feedback network access current passes through a current controller to form the current loop control loop; the voltage of the grid-side inductor is fed back to the output of the current loop through the virtual resistor link to form a damping branch, and the voltage of the common coupling point enters the traditional phase-locked loop link through the low-pass filter and forms an improved phase-locked loop through phase compensation. The optimal feedback coefficient of the damping branch is designed according to the optimal damping ratio, the low-pass filter parameters are designed according to the phase at the maximum resonant frequency, the reasonable proportional gain link is designed according to the improvement of the output impedance amplitude, the resonance of the current source type inverter can be effectively inhibited, the output impedance of the inverter is increased, and the output impedance of the inverter is improved. And the quality of the network access current of the current source type inverter and the stability margin of the current source type inverter in a weak power grid are improved, and the stability of the system is improved.

A method for hybrid control of grid-connected inverter based on time sharing of a voltage source and a current source including at least one control process, each control process including N+M control cycles. N may be a number of control cycles of a grid-connected inverter operating in a voltage source mode, M may be a number of control cycles of the grid-connected inverter operating in a current source mode. The control cycles of the grid-connected inverter operating in a voltage source mode and a current source mode may switch by counting. Aiming at a problem of being difficult to realize stable operation under large fluctuations in SCR, the present disclosure realizes a time-sharing control of the voltage source mode and the current source mode through a control algorithm, hybrids features of both mode, improves the stability of the grid-connected inverter, and realizes a stable operation under large fluctuations in SCR.