1546 results about "Current source" patented technology

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 an eddy current displacement sensor sine constant current source excitation method, and belongs to the technical field of sensor measurement and control. The method comprises the following steps: S1, generating positive and negative symmetric reference voltages through a reference voltage source circuit; s2, outputting a square wave control signal with adjustable frequency by the control chip, and driving a switching circuit to generate a square wave taking the positive and negative reference voltage as a level; s3, processing the square wave through a filter circuit to obtain a standard sine wave voltage signal; and S4, converting the sine voltage signal into sine constant current source excitation through a Howland current source circuit, and outputting the sine constant current source excitation to a sensor probe coil. According to the invention, through combination of digital control and analog conversion, the circuit structure is simplified, the cost is significantly reduced, and convenient adjustment of the output frequency and high stability and precision of the output current are realized at the same time.

The invention discloses a method for calculating the influence sensitivity of multiple stations and multiple control parameters on the short-circuit current of an alternating current system, and the method comprises the steps: building a calculation data model of the short-circuit current of a power grid, and enabling the model to comprise at least one new energy or energy storage device equivalent to a controlled current source; based on the calculation data model and the independent variable selected by each station, utilizing an iteration method to calculate the short-circuit current increment of each station; calculating the short-circuit current of each station fault point according to the short-circuit current increment; and calculating a sensitivity index of the independent variable relative to the short-circuit current of the specified fault point according to the short-circuit current.

An electronic device may include wireless circuitry. The wireless circuitry can include a first input transistor, a first capacitance neutralization having a source terminal coupled to a tail node, and a second order intermodulation generation circuit configured to produce second order intermodulation signals at the tail node. The wireless circuitry can further include a second input transistor and a second capacitance neutralization transistor having a source terminal coupled to the tail node. The first and second capacitance neutralization transistors can be cross-coupled with the input transistors. A fixed or adjustable current source can be coupled to the tail node. The second order intermodulation generation circuit can include a transistor biased in a weak inversion mode.

The invention discloses a multi-machine common-bus generator system stator grounding fault active arc extinction method based on online calculation of ground capacitance parameters, and the method comprises the following steps: S1, connecting a controllable current source in parallel with a secondary side of a generator neutral point grounding transformer, and injecting current into a neutral point; extracting a voltage component with the same frequency as the injection current, and calculating a ground capacitance parameter of the generator system on line through the voltage component and the injection current value; s2, measuring the three-phase phase voltage of the generator and the phase value of the zero-sequence current at the generator end of the generator, and solving the fundamental wave potential of a fault point based on the measured value; deriving a compensation current needing to be injected at the generator end side of the fault phase generator, and injecting the compensation current at the generator end; and S3, after compensating current is injected into the generator ends to realize arc extinguishing of fault points, measuring the generator end zero-sequence current phase of each generator again, and performing fault selective positioning, thereby determining a fault unit in the multi-generator common-mother system. According to the method, effective arc extinction can be realized, and the fault unit can be reliably judged.

The invention relates to a clock delay circuit for reducing interleaving distortion of a time interleaving pipeline ADC, and belongs to the field of analog-to-digital converters. Comprising a four-channel time-interleaved sampling switched capacitor array, an allowance amplifier module and four groups of delay control circuits, the four-channel time-interleaved sampling switched capacitor array comprises four sampling switched capacitor arrays which are connected in parallel; the four sampling switch capacitor arrays connected in parallel are all communicated with the allowance amplifier module; each group of delay control circuits is correspondingly connected with one sampling switch capacitor array; the delay control circuit comprises a clock generation circuit and a programmable current source array; the programmable current source array is connected with the clock generation circuit; the output end of the clock generation circuit is connected with the corresponding sampling switch capacitor array; according to the invention, the effect of reducing interleaving distortion in the four-channel time-interleaving pipeline analog-to-digital converter is realized, and the performance of the whole analog-to-digital converter is further improved.

A bridgeless power factor correction (PFC) circuit for reducing electromagnetic interference (EMI) is disclosed herein. A current source is placed in parallel with a switch of a low frequency leg. The current source may be turned on during zero crossings of the AC input voltage to limit current and reduce the rate of change in voltage. In turn, EMI may be advantageously reduced without the need for large passive filters or complicated circuitry.

The invention discloses a rapid three-dimensional electromagnetic simulation method and verification device for a large-scale uninsulated coil, and aims to solve the problems of large calculation load, difficulty in homogenization, poor field-circuit coupling convergence and low result precision of the three-dimensional simulation of the existing large-scale uninsulated coil. The simulation method comprises the following steps: establishing a homogenized coil which does not divide specific turns, and setting anisotropic resistivity; constructing a current source area intercepted on the coil body and a free turn-to-turn resistance area connected in parallel with the current source area; applying current source excitation according to an open loop / closed loop coil; and the precision is ensured through radial grid encryption and result convergence verification. The verification device comprises a three-dimensional multi-turn verification coil, a direct current source, a multi-direction alternating external field applying module and a voltage and magnetic field measuring unit, direct current is supplied, an alternating external field is applied, and the simulation accuracy is measured and verified in real time. The method is simplified in modeling, rapid in calculation, good in convergence and high in precision, adapts to open-loop / closed-loop and single-cake / multi-cake coils, and is suitable for large uninsulated superconducting coils in rotary and linear motors, nuclear fusion equipment and the like.

Implementations of a pre-emphasis signal processing system may include an output driver which may include a pre-emphasis transistor coupled with a steady state transistor, where gates of the pre-emphasis transistor and steady state transistor may be coupled together. The system may include a regulator voltage input coupled to a source of the pre-emphasis transistor; a first resistor coupled between a drain of the pre-emphasis transistor and an output of the output driver; and a second resistor coupled between the drain of the steady state transistor and the output of the output driver; and a pre-emphasis source including a current source coupled to a delay transistor, the delay transistor coupled with the output of the output driver.

One example discloses a communications circuit, including: a buffer having a buffer input and a buffer output; wherein the buffer includes a first path and a second path; wherein the first path includes, a first resistor coupled to the buffer input; a second resistor coupled to the buffer output; a current source having a first end and a second end; wherein the first resistor and the second resistor are coupled to a mid-point; wherein the first end of the current source is coupled to the mid-point; and wherein the second path includes a capacitor having a first end coupled to the buffer input and a second end coupled to the buffer output.

The invention discloses a high-efficiency single-stage bidirectional power conversion topological structure capable of realizing full-range soft switching and a control method of the high-efficiency single-stage bidirectional power conversion topological structure. In a single-stage bidirectional power conversion topology formed by double half bridges and a switch matrix, a controlled current source connected in parallel with a primary side of a second transformer is designed; the current on a bridge arm connected with the primary side of the second transformer can be effectively changed, so that the soft switching range of a switching tube on the bridge arm in a wide power transmission range is widened, and full-range soft switching in a power frequency period can be realized in any load range; the controlled current source is designed to only work before and after the switching moment of the primary side switching tube of the second transformer, the current stress of the switching tube can be effectively reduced, and meanwhile, the loss of the additional controlled current source is very small. According to the invention, the working range of the soft switching is widened, the additional loss caused by the soft switching is greatly reduced, higher efficiency and higher power density can be realized, and the cost advantage is realized.

The invention relates to the technical field of radio frequency integrated circuits, and discloses a dynamic bias C-type voltage-controlled oscillator based on a CMOS (complementary metal oxide semiconductor) process, the voltage-controlled oscillator adopts a C-type structure, a cross-coupled network adds two resistors and a capacitor on the basis of a cross-coupled transistor, a circuit works in the C type by adjusting bias voltage at a resistor end, and the voltage-controlled oscillator works in the C type. The C-type voltage-controlled oscillator, a tail current source, a variable capacitance network, a switched capacitor array and a fixed LC resonance network form a core structure of the C-type voltage-controlled oscillator capable of numerical control tuning and voltage-controlled tuning, so as to determine the working frequency of the circuit and realize numerical control and voltage-controlled tuning functions; and the operational amplifiers with two bandwidth modes are introduced, so that the problem of difficult oscillation starting is solved, and the oscillation starting speed and the phase noise performance in a stable state are considered at the same time.

The invention discloses a programmable low-temperature-drift under-voltage locking circuit, and the circuit comprises a reference current generation module which is used for outputting an initial reference current, and the input end of the reference current generation module is connected with a first reference voltage; the zero-temperature-drift current source array is used for generating reference current according to the initial reference current and the second reference voltage and mirroring the reference current to a plurality of parallel branches; the trimming module is used for adjusting the total current of the parallel branches by using a programmable resistor and a capacitor; the sampling module is used for sampling the total current and the power supply voltage of the parallel branches output by the trimming module; and the comparison output module is used for comparing the power supply voltage with a sampling voltage generated according to the programmable resistor and the total current of the parallel branches, and outputting a pair of differential signals. Through the reference current generation module, the zero-temperature-drift current source array, the trimming module, the sampling network and the voltage comparator, the problems that in an existing resistance voltage division type undervoltage locking scheme, a threshold value is fixed and cannot be adjusted, and the scheme is sensitive to temperature changes are solved.

Provided is a buffer circuit that can realize a wide dynamic range, a reduced area, and a reduced power consumption amount while maintaining low output impedance. The buffer circuit includes a first transistor, a current source, a second transistor, an output terminal, and first and second capacitors. The first transistor has a gate to which an input signal is input. The current source is connected to one terminal of the first transistor. The second transistor is connected to the other terminal of the first transistor. The output terminal is connected to the one terminal or the other terminal of the first transistor. The first and second capacitors are between the current source and the gate of the second transistor. The first transistor, the second transistor, and the first capacitor form a first feedback circuit. The first transistor, the current source, and the second capacitor form a second feedback circuit.

The invention discloses a current transformer based on decoupling compensation and an adjusting method thereof, and relates to the technical field of current measurement. The method comprises the following steps: establishing an error coupling matrix by data acquired by a current transformer; a decoupling compensation hardware module is designed, and decoupling compensation is carried out on the exciting current, the secondary load and the transient component; establishing a working condition parameter set, and constructing a training sample library by taking the working condition parameters as input and the compensation coefficients as output based on a BP neural network; through a clock synchronization module, it is ensured that output signals of the three compensation units and current signals of the secondary side of the mutual inductor are the same in frequency and phase; different working conditions are simulated through the standard current source, and the adjusted precision is recorded. According to the invention, through multi-dimensional error decoupling and combination of the BP neural network and the PID, hardware shunting and algorithm optimization are utilized to realize separated compensation of three errors, the method is adaptive to complex working conditions, and the adjustment precision of the compensation circuit is improved.

The invention belongs to the technical field of photoelectric fusion integrated circuits, and particularly discloses a parallel PWM expansion high-precision programmable DAC structure. The adjusting module is used for adjusting the thermo-optical phase shifter according to the received digital control signal; the DAC structure specifically comprises a pulse width modulation signal generator and a current source array, wherein the pulse width modulation signal generator is used for acquiring a low-order code element from the digital control signal to generate a pulse width modulation signal, and sending the pulse width modulation signal to the current source array; wherein the current source array is used for acquiring a high-order code element from the digital control signal to generate a high-order analog signal; a low-order analog signal is generated based on the pulse width modulation signal; and the processor is also used for weighting and accumulating the low-order analog signal and the high-order analog signal to obtain an analog control signal and outputting the analog control signal. The DAC structure is high in precision and simple in structure.

The invention relates to a direct current side coupling type super capacitor-battery hybrid energy storage system. According to the energy storage system, a super-capacitor module and a battery module are directly connected on the direct current side through a bidirectional DC / DC converter, the super-capacitor module is connected with a power grid through a current source type converter, the battery module is connected with the power grid through a voltage source type converter, and a modularized and extensible topological structure is formed. The system has multiple differentiated working modes, cooperative efficient operation of the super-capacitor and the battery can be achieved according to working conditions, high-frequency / short-time power is preferentially borne by the super-capacitor, and the battery is responsible for steady-state energy adjustment. And meanwhile, by virtue of the boosting capability of the current source type converter, the super capacitor can support the power grid in a short time and strong manner in a deep discharging manner. And the battery module charges the super capacitor module through the bidirectional DC / DC converter, so that the influence of frequent charging of the super capacitor on the grid-side electric energy quality is reduced. The method can effectively reduce the aging loss of the battery, improves the energy storage utilization efficiency and the power grid friendliness, assists the new energy consumption and the safe and stable operation of the power grid, and has economic and social benefits.

Certain aspects of the present disclosure provide techniques and apparatus for supplying power, including short circuit protection. One example power supply circuit generally includes a switching regulator including an output coupled to a first power supply node, a battery node for coupling to a battery, a switch coupled between the first power supply node and the battery node, a first transistor including a gate coupled to the first power supply node and a source coupled to a reference potential node of the power supply circuit, and a first current source or a resistive element, coupled between a power supply rail and a drain of the first transistor. The power supply circuit may be configured to detect a short circuit on the first power supply node and trigger an automatic fault protection (AFP) mode after completion of a soft start of a voltage on the first power supply node.

The invention relates to the technical field of battery charging protection circuits, and discloses a battery charging overcurrent checking circuit which comprises a triode PNP0, a substrate of a charging power tube PM0 is electrically connected with a base electrode of a PNP type triode PNP0, an emitting electrode of the triode PNP0 is connected with charging input voltage VIN, a collector electrode of the triode PNP0 is connected with one end of a resistor R1, and the other end of the resistor R1 is grounded; the negative input end of the comparator COMP is connected to a connection node of the triode PNP0 and the resistor R1 to obtain voltage VC, the output end of the reference voltage generation module is electrically connected with the positive input end of the comparator COMP to obtain reference voltage Vref, the output end of the comparator COMP outputs an overcurrent detection signal, substrate current of the charging power tube PM0 is adopted as a detection signal source, and the voltage Vref is detected through the detection signal source. A detection circuit is built by matching a PNP type triode PNP0 and a resistor R1, and an additional reference PMOS tube and a continuously working reference current source are omitted, so that the chip layout area is saved, and miniaturization of a charging chip is facilitated.

The invention discloses a temperature compensation circuit, a power amplifier and a radio frequency front-end module. The temperature compensation circuit comprises a temperature compensation module, a current source module and a control module. The temperature compensation module is used for outputting a first temperature compensation voltage under the condition that the environment temperature is smaller than or equal to a first temperature threshold value; the current source module is connected between the temperature compensation module and the output port and is used for converting the temperature compensation voltage output by the temperature compensation module into control current; the current source module is provided with at least two current adjusting gears, and the control module is connected with the current source module. When the first temperature compensation voltage output by the temperature compensation module is in positive correlation with the environment temperature, and the environment temperature is smaller than or equal to a first temperature threshold value (namely, the low-temperature environment), the control current is reduced accordingly, so that the offset signal of the compensated power amplifier is synchronously reduced, and the offset signal of the power amplifier is synchronously reduced. The working gain of the power amplifier in a low-temperature environment can be reduced, so that the durability of the power amplifier is improved.

The invention relates to the technical field of electromagnetic transient simulation, in particular to an electromagnetic transient simulation decoupling method, system and device based on a single-impedance branch and a medium, and the method comprises the steps: dividing a system to be simulated into two subsystems which are connected through the single-impedance branch, and carrying out the equivalent reconstruction to form a reconstructed branch model; establishing a discrete state space equation based on the reconstructed branch model; according to the main step length, the number of sub-steps meeting the stability condition is determined based on a small-step synthesis algorithm, and the main step length is equally divided into differential step lengths; in each main step length interval, performing iterative calculation on the state-space equation by using a differential step length to obtain a branch current and a capacitor voltage at the next moment; and injecting the calculated branch current serving as a known current source into an original network equation, solving in parallel to obtain the port voltage of the subsystem, and completing decoupling calculation and promoting simulation. According to the method, effective decoupling of the universal single-impedance branch can be realized, and the applicability, the numerical stability and the calculation efficiency of parallel simulation are improved.

The invention discloses a chip radiation emission test method, device and equipment and a storage medium, and relates to the technical field of chip electromagnetic compatibility design and simulation, and the method comprises the steps: constructing a target packaging body model corresponding to a to-be-tested chip; constructing a target test circuit board model corresponding to the to-be-tested chip; determining a target scattering parameter corresponding to the target to-be-measured electromagnetic structure; based on the target scattering parameters, the target to-be-tested electromagnetic structure is connected to the first simulation model, the second simulation model and a voltage source model and a current source model matched with the target to-be-tested electromagnetic structure, and a test link of the target to-be-tested electromagnetic structure is constructed; performing frequency response analysis on the test link, and determining radiation emission energy data of an output port of the transverse electromagnetic wave cell model; and generating a corresponding amplitude-frequency characteristic curve based on the radiation emission energy data. According to the method, the early simulation test of the radiation emission characteristic of the chip can be realized, and the research and development efficiency of the chip is remarkably improved.

A neuromorphic device includes a plurality of resistor lines, each comprising a plurality of resistors that are serially connected to each other; one or more current sources configured to control a current flowing in each of the resistor lines to a respective current value; a plurality of capacitors configured to be electrically connected to each of the resistor lines and to sample respective voltage of each of the resistor lines representing results of neuromorphic operations; and a switch configured to connect the plurality of the capacitors in parallel after the sampling the respective voltage of each of the resistor lines, to output a sum of the results of neuromorphic operations.

The invention relates to the technical field of amplifiers, in particular to a variable gain amplifier with a wide linear gain range and a working method, and the variable gain amplifier comprises the steps that a linear gain generation circuit receives a differential input signal and provides gain-adjustable differential output based on linear control voltage; the linear gain generation circuit comprises at least one stage of variable gain unit which comprises differential input pair transistors MN1 and MN2. The load resistor elements R1 and R2 are connected between the power supply voltage VDD and the drain electrodes of the differential input pair transistors MN1 and MN2; the tail current source MN3 provides bias current for the differential input pair transistors MN1 and MN2; the active load network is connected between the drain electrodes of the differential input pair transistors MN1 and MN2 and the ground; the active load network comprises a control tube MN8, the control tube MN8 works in a sub-threshold region, a grid electrode receives linear control voltage, equivalent impedance of the active load network is enabled to be in exponential change along with the linear control voltage through exponential I-V characteristics, and dB linear gain adjustment of the variable gain unit is achieved.

The invention discloses a relay protection short-circuit current calculation method and device of a photovoltaic-energy storage combined system. The method comprises the steps that an inverter equivalent mathematical model of the photovoltaic-energy storage combined power generation system is established, and the inverter equivalent mathematical model enables an inverter in a fault state to be equivalent to a positive sequence current source; based on the inverter equivalent mathematical model, in combination with a low voltage ride-through control strategy, determining a function relationship between the output of the positive sequence current source and the positive sequence voltage of the grid-connected point, and forming a fault current calculation expression; and obtaining positive sequence voltage information of the grid-connected point when the power grid fails, substituting the positive sequence voltage information into the fault current calculation expression, and calculating to obtain the short-circuit current provided by the photovoltaic-energy storage combined system.

A temperature sensor device is capable of measuring minute temperature changes while being manufactured at low cost without needing a high performance IC tester. A temperature sensor device includes a temperature sensor circuit 2 and a temperature sensor 1. The temperature sensor 1 includes a PN junction element 15 which is a temperature sensing element, a variable current source which supplies different forward currents of at least two values to the PN junction element 15 and a constant voltage source 16 which outputs a constant voltage having the same temperature properties as a forward voltage of the PN junction element 15.

A control device (100) for controlling a number N, with N ≥ 1, of actuators (200) for actuating N optical elements (310) of an optical system (300), comprising a control node (K2) coupling to the actuator (200) for providing a control voltage (V2) for the actuator (200), and 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 controlled current source (112) and a holding capacitor (113) for maintaining the level of the provided output voltage (V3), wherein the controlled current source (112) comprises a transistor (114), whose gate terminal can be controlled by an adjustable first control signal (S1),and has an adjustable resistor (115) coupled to the transistor (114).

The invention provides a static frequency divider with adjustable self-resonant frequency and a clock circuit, and relates to the technical field of circuits, the frequency divider comprises a master latch and a slave latch; each of the master latch and the slave latch comprises a current source, an adjustable resistor unit, a differential amplification pair, a cross coupling pair and a load resistor pair; the current source is connected with the first current branch and the second current branch, the first current branch is connected with the load resistor pair through the differential amplification pair, the second current branch is connected with the load resistor pair through the cross coupling pair, the first current branch is provided with a first switching tube, and the second current branch is provided with a second switching tube and an adjustable resistor unit which are connected in series. Thus, the adjustable resistor unit is configured on the second current branch, association between the resistance value of the adjustable resistor unit and the frequency of the frequency divider is established, a hardware basis is provided for frequency adjustability, and frequency requirements of different scenes are met by adjusting the resistance value of the adjustable resistor unit and adjusting the self-resonant frequency of the frequency divider.

A differential pulse conveyor system includes detectable markers arranged in series on moving parts of the conveyor system. A stationary sensor positioned near the marker generates a signal to place the marker near the sensor when the moving part is within a first range of motion, and the sensor does not generate a signal when the moving part is outside the first range of motion. The sensor signal causes a current regulating device to adjust the current from a current source to operate a motor to power a conveyor tray to move at a first acceleration rate in a first mode, and the signal activation causes the current regulating device to operate the motor to power the conveyor tray to move at a second acceleration rate in a second mode. The markers can be positioned to optimize the timing of the current mode.