1502 results about "Feedback circuits" patented technology

The invention discloses a high-current wide-capacitance-range LDO (Low Dropout Regulator) based on a frequency compensation circuit. The LDO comprises a first-stage operational amplifier, a second-stage operational amplifier and a third-stage operational amplifier The secondary operational amplifier is used for carrying out secondary amplification on the amplified error signal; the driving circuit is used for enhancing the driving capability of the error signal subjected to secondary amplification; the current output circuit is used for adjusting the output current of the output demand according to the secondary amplified error signal with the enhanced driving capability and the input voltage; the feedback circuit is used for generating new feedback voltage according to the output current; the first-stage operational amplifier is also used for amplifying a new error signal; and the frequency compensation circuit is used for adjusting the positions of a plurality of zero poles in the new error signal according to the output current by utilizing the multi-zero pole dynamic compensation branch and the current buffer compensation branch so as to offset a secondary pole and widen the whole unit gain bandwidth at the same time to obtain an adjusted error signal. According to the invention, a large bandwidth can still be obtained in a large current output range and a large load capacitance range.

A method for equalizing a data signal includes providing a data signal to a pair of input transistors that provides an output signal, contributing to the output signal, a first current or voltage that has a magnitude determined by a first weighted feedback signal using a first decision-feedback circuit that includes a first pullup circuit coupled to a drain of a first input transistor, and a first pulldown circuit coupled to the drain of the first input transistor, and contributing to the output signal, a second current or voltage that has a magnitude determined by a second weighted feedback signal using a second decision-feedback circuit that includes a second pullup circuit coupled between a drain of a second input transistor and the first voltage rail, and a second pulldown circuit coupled between the drain of the second input transistor and a second voltage rail.

The embodiment of the invention provides a closed-loop control method for power driving and protection, and the method comprises the steps: constructing a voltage feedback type circuit through a high-speed operational amplifier, and forming a closed-loop gain structure through a feedback network of the voltage feedback type circuit; the load current of the output end of the voltage feedback type circuit is monitored in real time, and when the load current exceeds a first set threshold value, a protection mechanism is triggered to turn off the output stage; the power-on surge current is limited through the soft start control circuit; phase information of a load reflection coefficient is obtained, an inductance / capacitance combination of the variable dynamic impedance matching network is selected according to phase information table look-up, inductance / capacitance parameters are switched through a relay, and the transmission standing-wave ratio between the power amplifier and a load is optimized; monitoring the temperature of the radiating fin of the power tube, and dynamically adjusting the resistance value of the feedback network; and performing cooperative control of short-circuit protection, over-temperature protection and surge suppression according to the priority. According to the embodiment of the invention, the performance bottleneck in a load fluctuation scene is broken through.

The invention provides a common-mode feedback circuit and a differential amplifier thereof, the common-mode feedback circuit comprises a sampling circuit and an amplifier circuit, the sampling circuit comprises a first input end, a second input end and a first output end, the first input end receives a first differential signal Voutp, and the second input end receives a second differential signal Voutn; the level shift module comprises a third input end, a fourth input end and a second output end, receives a common-mode signal VCMS and a reference common-mode signal VOCM output by the sampling circuit, and adjusts the common mode of the common-mode signal VCMS and the reference common-mode signal VOCM to enable the second output end to output a common-mode feedback signal VCMFB processed by the level shift module; the amplifier circuit receives a common mode feedback signal VCMFB. After the technical scheme is adopted, the same speed as that of a differential loop can be realized, the current of a main operational amplifier can be multiplexed, the power consumption of a common-mode loop is far lower than that of a main loop, and meanwhile, the common-mode level can be randomly adjusted.

According to the driving control circuit for the electrostatic chuck power supply and the electrostatic chuck power supply, the driving control circuit is arranged in the electrostatic chuck power supply, a high-voltage output voltage signal of a high-voltage amplifying circuit can be obtained through a signal generating and processing feedback circuit, and according to a negative feedback adjusting mechanism, the driving control circuit is used for driving the electrostatic chuck power supply. A power supply waveform control signal for controlling a high-voltage amplification circuit to output a high-voltage output voltage signal is adjusted, and the high-voltage output voltage signal output by the high-voltage amplification circuit is adjusted to be output, so that the effect of controlling the signal precision of the high-voltage output voltage signal output by the electrostatic chuck power supply is achieved, and the output stability of the electrostatic chuck power supply is improved. Therefore, the stability of an electrostatic field generated by the electrostatic chuck is guaranteed, and the wafer fixing process precision of the electrostatic chuck is ensured.

A control device for a switching voltage regulator includes: a first detector of a first measurement signal indicative of a current flowing in a first side of the regulator, and providing a first comparison signal as a function of a first threshold; a second detector of a second measurement signal indicative of a current flowing in a second side of the regulator, and providing a second comparison signal as a function of a second threshold; a driving-signal generation circuit which generates a switching control signal from the first comparison signal to drive the switching circuit; a calibration circuit which receives an alert signal indicative of the first threshold, compares the alert signal and the second comparison signal, and provides a calibration signal in response; and a feedback circuit which provides a control signal as a function of an error signal and of the calibration signal.

The invention provides a fully differential operational amplifier circuit and an operational amplifier. The fully differential operational amplifier circuit comprises an input stage circuit, a gain stage circuit and a common-mode feedback circuit, the input stage circuit is used for processing a differential input voltage signal, converting the differential input voltage signal into a differential current signal and transmitting the differential current signal to the gain stage circuit; the gain stage circuit is used for performing gain processing on the differential current signal and outputting a target differential voltage signal; the common-mode feedback circuit is used for detecting the common-mode voltage of the target differential voltage signal, generating a common-mode feedback signal and transmitting the common-mode feedback signal to the gain-stage circuit to stabilize the common-mode voltage; wherein the gain stage circuit comprises a gain enhancement circuit, and the gain enhancement circuit is used for increasing the output impedance of the gain stage circuit. According to the chopping operational amplifier, the input stage circuit, the gain stage circuit, the common mode feedback circuit and the gain enhancement circuit are combined, so that the precision and the sensitivity of the chopping operational amplifier are improved.

The invention belongs to the technical field of direct current monitoring, and discloses a TMR-based open-close type direct current leakage current detection device, which comprises a magnetic core, one or more pairs of TMR sensors, a secondary side feedback coil and a main control circuit, and is characterized in that the magnetic core is provided with air gaps which are oppositely arranged; the TMR sensors are symmetrically arranged in the air gap; the secondary side feedback coil is wound on the surface of the magnetic core and forms closed-loop control with the main control circuit; the main control circuit comprises an acquisition feedback circuit, a secondary side detection circuit and a main control chip, the acquisition feedback circuit acquires signals of the TMR sensor under the control of the main control chip, generates feedback current and inputs the feedback current to the secondary side feedback coil, and the secondary side detection circuit is connected between the secondary side feedback coil and the main control chip. And the main control chip collects the secondary side voltage of the secondary side detection circuit and calculates to obtain the direct current leakage current. According to the invention, direct current leakage current detection with high sensitivity, low drift and strong anti-interference capability is realized under the open-close structure, and the requirements of a modern electric power system on continuity, safety and maintainability are met.

The invention discloses a direct current SSPC current limiting control system and a control method thereof, and relates to the field of power electronics and electricians. The RC network generates a control voltage according to the switch control signal; the driving power amplification circuit carries out power amplification processing on the control voltage; the main power circuit conducts or cuts off the branch power distribution channel according to the processed voltage so as to provide a current path; the current-limiting state judgment circuit judges whether to enter or exit a current-limiting state according to information data fed back by the feedback circuit, and outputs a signal to the current closed-loop current-limiting control circuit; and the current closed-loop current-limiting control circuit receives the signal output by the current-limiting state judgment circuit and adjusts a control voltage corresponding to a main branch power tube in the RC network according to the SSPC channel current so as to realize constant-current control of the power distribution channel. The invention aims to improve the stability and thermal reliability of direct current SSPC current-limiting control.

The invention provides a correlated double-sampling program-controlled gain amplifier for a high-energy particle detection pixel sensor and an implementation method, and solves the technical problem that a large dynamic range and high readout precision cannot be considered at the same time during existing high-energy particle detection. The circuit comprises a correlated double-sampling circuit, a signal polarity conversion circuit, an amplification feedback circuit and a configuration automatic judgment circuit. The correlated double sampling circuit is used for performing double sampling on the output voltage of the pixel signal to obtain twice sampling voltage; the configuration automatic judgment circuit is used for selecting configurations for switching according to the voltage difference between the two sampling voltages to obtain an output signal; and the amplification feedback circuit is used for performing fixed gain voltage amplification on the output signal to obtain an amplified voltage signal. The circuit can be widely applied to the technical field of integrated circuits.

The invention discloses an electric energy discharge control device. The energy storage circuit is used for storing potential storage electric energy; the bleeder circuit is used for releasing the potential storage electric energy through a bleeder resistor and a bleeder transistor which are connected in series; the reference voltage setting circuit is used for outputting a reference voltage signal; the bleeder sampling feedback circuit is used for outputting a bleeder sampling feedback electric signal according to the bleeder sampling current of the bleeder resistor; the post-stage voltage feedback circuit is used for outputting a post-stage voltage feedback electric signal according to the potential storage voltage; and the conduction degree of the discharge transistor is controlled according to the post-stage voltage feedback electric signal, the reference voltage signal and the discharge current collection feedback electric signal. The conduction degree of the bleeder transistor is dynamically controlled according to the bleeder current collection feedback electric signal and the post-stage voltage feedback electric signal, so that the change of potential storage electric energy of the energy storage device is dynamically adapted, the bleeder power and the current of the bleeder circuit are stable and controllable, and a higher bleeder rate can be realized under the condition that the bleeder power and the current are kept unchanged.

The utility model provides a test system for Mini LED drive chips, which is applied to the technical field of liquid crystal display and specifically comprises a host, an FPGA (field programmable gate array) master control module, a plurality of Mini LED drive chips, a plurality of cement resistors and a plurality of LED lamp beads with the same number as the cement resistors, then, through a mode of adding a cement resistor and an LED lamp bead in each channel of each Mini LED driving chip, the test requirement difference of different clients is considered on the test system, and through a mode of further adding an FPGA main control module, an automatic return circuit mechanism is added in the test system; wherein the host is in communication connection with the FP GA main control module through one path of UART bus so as to send a test signal to the FPGA main control module or receive the running state of each Mini LED driving chip returned by the FPGA main control module in real time, so that high-temperature and high-humidity accurate test and automatic recording of test results are realized, manpower and material resources are saved, and the test efficiency is improved.

A voltage meter includes a sampler, a gain circuit, an accumulator and a feedback circuit. The sampler samples an input signal to generate a series of first signals and a series of second signals. The gain circuit, coupled to the sampler, modifies at least one of the series of first signals and the series of second signals, to generate a series of modified first signals and a series of modified second signals. The accumulator, coupled to the gain circuit, accumulates an operational result of the series of modified first signals and the series of modified second signals, to generate an accumulation result. The feedback circuit, coupled between the accumulator and the sampler, sends a feedback signal back to the sampler according to the accumulation result.

An adaptive IGBT active drive circuit is divided into two parts: a gate drive circuit, and a feedback circuit. The gate drive circuit includes a totem pole unit, and multi-level resistance switching is achieved by using a totem pole parallel structure. The feedback circuit includes a comparison unit, and a logic unit. The comparison unit includes divided resistors, sampling resistors, and a comparator. Internal currents, after passing through the sampling resistor, are compared with current comparison thresholds of complementary transistors to output a digital signal to participate in control of the totem pole. The logic unit is responsible for logically combining a PWM signal and a signal output by the comparison unit to obtain a driving signal of the totem pole.

The invention discloses a PWM-based motor signal feedback control method and device, and the device comprises a signal feedback circuit which is disposed on a motor or can be connected with the motor so as to receive a motor feedback signal, and can output a control signal. The method comprises the following steps: setting N different first function relational expressions established by motor state feedback signals and PWM duty ratios d in a main control board, and defining a PWM duty ratio range for each first function relational expression, and the PWM duty ratio ranges are not overlapped; setting A different second function relational expressions established by the motor state feedback signals and the PWM frequency f in the main control board, and defining a PWM frequency f range for each second function relational expression, and the PWM frequency ranges are not overlapped; the main control board accurately adjusts the target value of the motor in real time according to the multiple motor state feedback signals, meanwhile, the hardware structure of the main control board and the hardware structure of the motor are simplified, and cost is reduced.

The invention relates to the technical field of power supply circuits, and discloses a gallium nitride power chip power supply which comprises an AC input, an EMI filter circuit, a gallium nitride power switch, a switch transformer, a rectification filter circuit, a DC output, a voltage detection feedback circuit, a PWM control circuit, a current limiting circuit and a temperature protection circuit. The AC input, the EMI filter circuit, the gallium nitride power switch, the switch transformer, the rectification filter circuit and the DC output are connected in sequence; the rectification filter circuit is also connected with the voltage detection feedback circuit, and the voltage detection feedback circuit is connected with the PWM control circuit. The output end of the gallium nitride power switch is further connected with the circuit limiting circuit, and the current limiting circuit is connected with the PWM control circuit through the temperature protection circuit. The power supply of the gallium nitride power chip provided by the invention has the advantages of more stable output, larger adjustment range, stronger anti-interference capability and better overload and temperature protection performance.

The invention discloses a fan speed regulation circuit, including a feedback circuit for obtaining the motor temperature and adjusting the fan enable signal and then outputting it; a compensation circuit 1 for obtaining the fan enable signal and the fan speed and then outputting a level signal after comparison; and a compensation circuit 2 for obtaining the level signal and adjusting the fan speed. The invention realizes dynamic regulation, does not occupy DSP resources, uses a PWM control chip to adjust the fan PWM control signal, and then achieves the purpose of speed regulation, has a simple circuit, and requires fewer power devices; has a high switching frequency, is easy to be continuous in current, has fewer harmonics, and has relatively small losses and heat generation; has good low-speed performance, high steady-speed accuracy, and a wide speed regulation range; the power switch device works in a switching state, has a small conduction loss, and when the switching frequency is appropriate, the switching loss is also small, so the efficiency is high.

Integrated circuit transceivers having digital timing recovery loops with phase interpolation may incorporate dynamic loop gains to compensate for nonlinearities of the phase interpolation. An illustrative receiver circuit includes: a phase interpolator, a sampling element, a timing error estimator, and a feedback circuit. The phase interpolator provides a sampling signal by applying a phase shift to a clock signal in response to a phase control signal. The sampling element produces a digital receive signal by sampling an analog receive signal in accordance with the sampling signal. The timing error estimator produces a timing error signal indicating an estimated timing error of the sampling signal relative to the analog receive signal. The feedback circuit derives the phase control signal from the timing error signal using a scaling element configured to scale the estimated timing error by a scale factor that depends on the phase control signal.

In a calibrated digital phase-locked-loop (DPLL) circuit, during a normal operating mode, a control value provided to a digitally controlled oscillator (DCO) is updated by a feedback circuit to keep an output clock generated by the DCO synchronized with a reference clock. The feedback circuit includes a time-to-digital converter (TDC) circuit to measure a phase difference as a time interval. In a calibration operating mode of the calibrated DPLL circuit, calibration of a resolution of a time measurement of the time interval measured by the TDC is performed in the feedback circuit while the control value provided to the DCO is kept constant. Calibrating the TDCs in each of the DPLLs in an integrated circuit (IC) to a nominal resolution in this manner improves synchronization of the clock domains. In some examples, the TDC circuit is a Vernier type circuit and calibration sets a delay difference to a nominal resolution.

The invention provides a low-noise amplification circuit, a radio frequency front-end module and an electronic terminal.The low-noise amplification circuit comprises an input matching adjustment circuit, a common-source amplification circuit, a first inductor, an inter-stage feedback circuit, a common-gate amplification circuit, an input and output feedback circuit, an output matching adjustment circuit and an output attenuation circuit; the common-source amplification circuit comprises at least two first signal amplification units; each first signal amplification unit comprises a first field effect transistor; the common-gate amplification circuit comprises at least two second signal amplification units; and each second signal amplification unit comprises a second field effect transistor. According to the low-noise amplification circuit, transconductance nonlinearity of devices under different bias signals can be mutually counteracted, so that the linearity fluctuation of the low-noise amplification circuit at different temperatures is optimized, and the linearity of the low-noise amplification circuit is kept basically not to change along with the temperature change.

The invention relates to the technical field of dust combustion, and provides a dust explosion combustion experiment device in order to solve the problems that an existing dust explosion combustion experiment device is insufficient in parameter control precision, and an experiment multi-focus single variable lacks a dust removing mechanism and a safety protection measure, and the dust explosion combustion experiment device comprises an experiment table which is provided with a power chamber and an equipment chamber; one side of the experiment table is hinged with an access door, two sides of the top of the experiment table are provided with conveying main pipes extending to the equipment chamber, a power supply assembly is arranged in the electric power chamber; the protective shell assembly comprises an outer shell and an inner shell; a plurality of exhaust pipes are arranged at the top of the inner shell; the dust generation assembly comprises a plurality of dust storage tanks and an air compressor; the ignition control assembly comprises a pulse igniter, a flame detection feedback circuit and an ignition head; the environment adjusting assembly comprises a box body, an oxygen tank and a humidifier, wherein the oxygen tank and the humidifier are arranged in the box body. The device has the advantages that the dust concentration is accurately regulated and controlled, the environmental parameters are dynamically coupled and controlled, dust residues are rapidly removed, and the experiment safety is high.

The invention provides a level shifter and a memory device including the same. The level shifter includes: a medium voltage output circuit configured to output a medium voltage based on an input voltage stepped between a first voltage level and a second voltage level; a feedback circuit configured to output a feedback voltage and an output voltage stepped between a positive target voltage level and a negative target voltage level based on the positive target voltage, the negative target voltage, and the medium voltage; a pull-up voltage control circuit configured to output the first voltage or the positive target voltage to the medium voltage output circuit based on the feedback voltage; and a pull-down voltage control circuit configured to output the second voltage or the negative target voltage to the medium voltage output circuit based on the feedback voltage.

The invention relates to the technical field of semiconductor integrated circuits, and provides a low-dropout linear voltage stabilizing circuit which comprises a power transistor, a current feedback circuit, an error amplifying circuit and a driving circuit. The first end of the power transistor receives an input voltage, and the second end of the power transistor provides an output voltage; the current feedback circuit samples the current flowing through the power transistor and generates a current feedback signal representing the current flowing through the power transistor; the error amplification circuit receives a voltage feedback signal representing an output voltage, and amplifies a difference value between the voltage feedback signal and a reference voltage signal so as to output an error signal at an output end of the error amplification circuit; the first end of a first transistor of the driving circuit receives a current feedback signal, the control end of the first transistor receives an error signal, and the first end of the first transistor serves as the output end of the driving circuit and is coupled to the control end of the power transistor. The low-dropout linear voltage stabilizing circuit can realize frequency compensation, increase bandwidth and improve stability.

Circuits and methods that limit current through power FETs of power converter to reduce damaging current in-rush events, independent of switching frequency, device mismatches, and PVT variations. Embodiments utilize a closed-loop feedback circuit and / or a calibrated compensation circuit to regulate, substantially independent of frequency, the control voltage VGATE applied to a power FET gate. In a reduced gate-drive mode, connecting a feedback or compensation circuit to the gate of an LDO source-follower FET allows the gate voltage to be regulated to control the LDO output voltage to a final inverter coupled to the gate of a power FET so that VGATE is adjusted to provide a reduced gate-drive to the power FET; connecting to the output of the LDO allows the LDO output voltage to the final inverter to be directly regulated to adjust VGATE; connecting to the gate of the power FET allows VGATE to be directly set.

The invention discloses a high-gain active pixel circuit and an image sensor, relates to the technical field of electronic circuits, and is used for reducing the time required by the pixel circuit to complete exposure of a frame of image. The high-gain active pixel circuit comprises a photosensitive circuit, a feedback circuit and an amplifying circuit, wherein a first end of the photosensitive circuit is coupled to a grounding end, and the photosensitive circuit is configured to generate an exposure current according to the intensity of received illumination; the first end of the feedback circuit is coupled to the second end of the photosensitive circuit, and the feedback circuit is configured to input exposure current and clamp the voltage at the second end of the photosensitive circuit; the output end of the amplification circuit is coupled to the second end of the feedback circuit, the input end of the amplification circuit is coupled to the second end of the photosensitive circuit, and the amplification circuit is configured to clamp the voltage at the second end of the photosensitive circuit to a preset voltage through the feedback circuit.

A voltage regulator includes an input power supply node, an output regulated power supply node, a flipped voltage follower circuit, and a compensation capacitor. The flipped voltage follower circuit includes an output transistor configured as a common-source amplifier circuit. A source terminal of the output transistor is coupled to the input power supply node and a drain terminal of the output transistor is coupled to the output regulated power supply node. The flipped voltage follower circuit includes a folded cascode feedback circuit. The folded cascode feedback circuit includes a folding node. The folded cascode feedback circuit is configured to receive an output regulated voltage on the output regulated power supply node and to provide a feedback signal to a gate terminal of the output transistor. The compensation capacitor is coupled to the output regulated power supply node and the folding node.

A leakage current detection circuit and a leakage current protection circuit are disclosed. The leakage current detection circuit includes a mutual inductance module, an excitation module, a signal processing module, a feedback self-check module and a calculation module. The mutual inductance module includes a magnetic core, a first winding and a second winding. The excitation module is configured for producing an excitation current in the first winding. The signal processing module is configured for processing the output voltage signal of the first winding and outputting a processed signal, and the voltage signal corresponding to the excitation current is filtered out of the processed signal. The feedback self-check module includes a feedback circuit and a self-check circuit. The calculation module is configured for analyzing the leakage current according to the processed signals and outputting the self-check signal in the self-check mode.

The invention relates to the technical field of magnetic shielding, and provides a demagnetization method and device for a magnetic shielding device, electronic equipment and a readable storage medium, and the method comprises the steps: collecting a feedback circuit signal of a target magnetic shielding device through a voltage and current collection unit; analyzing the feedback circuit signal by using a signal acquisition processor, determining the current degaussing demand of the target magnetic shielding device, and calculating a degaussing pulse parameter matched with the current degaussing demand; a pulse generating unit is used for generating a target pulse with the adjustable pulse width according to the degaussing pulse parameters, the target pulse is a bipolar square wave pulse, and the adjusting interval of the pulse width comprises the millisecond level and the nanosecond level; and utilizing a pulse switching unit to act the target pulse on the target magnetic shielding device, so that the target magnetic shielding device is subjected to magnetic saturation or magnetic fading. According to the technical scheme provided by one or more embodiments of the invention, the average power demand of the degaussing power supply can be reduced, and the degaussing effect can be improved.

A cascade amplification circuit module based on complementary parameter amplifiers belongs to the technical field of integrated circuit amplifiers and comprises a first-stage complementary parameter amplifier (CPA) and a second-stage amplifier (floating inverting type or transconductance resistance type). The first-stage CPA adopts an NMOS and PMOS complementary structure, passive amplification is achieved through grid multiplexing, a grid capacitor is used for storing signals in the sampling stage, a depletion layer capacitor is switched to improve gain in the amplification stage, common-mode voltage is stabilized through complementary design, and an extra feedback circuit is not needed. And the second-stage amplifier provides driving capability and is combined with passive gain to suppress noise. The cascade structure does not need frequency compensation, the design is simplified, the problem of balancing gain, noise and power consumption of a traditional amplifier is solved, and the cascade amplifier has the advantages of being high in energy efficiency and low in complexity.

A power converter includes a transformer, a resonant capacitor, a high-side transistor, a low-side transistor, a rectification circuit, a feedback circuit, a detection circuit, and a control circuit. The transformer includes a primary coil coupled to a switch node and a secondary coil. The resonant capacitor is coupled to the primary coil. The high-side transistor provides an input voltage to the switch node, and the low-side transistor couples the switch node to the ground. The rectification circuit converts the energy of the secondary coil into an output voltage. The feedback circuit compares the output voltage with a reference voltage to generate a compensation signal. The detection circuit generates a current detection signal and a voltage detection signal. The control circuit drives the high-side transistor and the low-side transistor based on the current detection signal, the voltage detection signal, the compensation signal, and the input signal.