1501 results about "Operational amplifier" patented technology

The invention discloses a high-voltage power amplifier with an over-temperature and over-current protection circuit, and relates to the technical field of integrated circuits. The high-voltage operational amplifier comprises a high-voltage operational amplifier core unit and a self-adaptive protection circuit unit, the high-voltage operational amplifier core unit comprises a rail-to-rail input stage, a gain amplification stage and an AB type push-pull output stage which are sequentially cascaded, and the AB type push-pull output stage comprises a PMOS upper power tube and an NMOS lower power tube; the self-adaptive protection circuit unit comprises a PMOS (P-channel Metal Oxide Semiconductor) current-limiting protection circuit, an NMOS (N-channel Metal Oxide Semiconductor) current-limiting protection circuit and an over-temperature protection circuit; the PMOS current-limiting protection circuit is used for generating a high-voltage domain over-current control signal when the power tube on the PMOS is over-current; the NMOS current-limiting protection circuit is used for generating a low-voltage domain overcurrent control signal when the NMOS lower power tube is in overcurrent; the over-temperature protection circuit is used for generating high-voltage domain over-temperature turn-off signals and low-voltage domain over-temperature turn-off signals when the amplifier is over-temperature; and finally, carrying out logic synthesis on the corresponding over-current control signal and the over-temperature turn-off signal to generate a gate clamping signal.

The invention provides a signal acquisition system of a photoelectric detector. In the signal acquisition system, a transimpedance pre-amplification circuit is arranged at the output end of the photoelectric detector, and a passive high-pass filter circuit is connected between the transimpedance pre-amplification circuit and a post-voltage amplification circuit. And a feedback network is formed in the transimpedance pre-amplification circuit and is used for converting a current signal output by the photoelectric detector into a proportional first voltage signal and outputting the proportional first voltage signal. The filter circuit is a third-order LC high-pass filter circuit and is used for suppressing direct current, low frequency and self-beat frequency components and keeping a 10-90MHz pass band flat. The rear voltage amplification circuit adopts a voltage amplification structure of a voltage operational amplifier, the voltage gain Av is 6-10, and the super-band gain is limited through a shunt capacitor. According to the embodiment of the invention, through the structure and parameter setting, the noise gain peak value is suppressed, and the system stability is improved.

The invention discloses an ultrahigh-precision low-noise band-gap reference circuit, and relates to the technical field of integrated circuit design, the ultrahigh-precision low-noise band-gap reference circuit comprises a starting turn-off circuit, a reference core circuit, a high-order temperature compensation circuit and a digital trimming circuit, the starting turn-off circuit is connected with the reference core circuit, and the high-order temperature compensation circuit is connected with the digital trimming circuit through a Brokaw type band-gap reference topological structure. Accurate compensation of the voltage is achieved through deep negative feedback of the operational amplifier and a high-order temperature compensation circuit, and the temperature drift of the reference voltage is as low as 0.5-2 ppm / DEG C (-40 DEG C to 130 DEG C) and is increased by 5-10 times compared with a traditional band-gap reference (5-10 ppm / DEG C). The power consumption of the system can be saved by turning off the circuit when the circuit is not used, meanwhile, the digital trimming module is added to replace laser trimming in traditional engineering, the upper limit of the trimming range is improved, high-order temperature compensation and the digital trimming circuit are introduced, the precision of output voltage is improved, different devices are replaced, and the noise of the circuit is reduced. The problems that a traditional high-voltage band-gap reference temperature coefficient is high and noise is large are solved.

The invention belongs to the technical field of analog integrated circuit design and memory read-write, and provides a multi-valued RRAM read-write circuit with a write-and-read function. The multi-valued RRAM read-write circuit is a multi-port device capable of performing read-write simultaneously, in write operation, a low dropout regulator is utilized to provide voltage for the RRAM circuit and the standard resistance circuit, mirror current is generated, the resistance value of the RRAM is set to be the total resistance of the standard resistance circuit, an operational amplifier is connected into the circuit through a CMOS switch, and feedback is formed to stabilize the voltage at the two ends of the RRAM; and in the read operation, the CMOS switch is used for disconnecting the operational amplifier, and the voltage at the two ends of the RRAM device is directly read. Compared with an existing multi-valued read-write circuit, the multi-valued RRAM read-write circuit has the advantages that write-and-read multi-valued RRAM read-write is realized, and meanwhile, the read-write circuit is not separated, so that the write-in speed is increased, and the area of the read-write circuit is saved.

The invention discloses a left auricle plugging device provided with a real-time atrial pressure monitoring chip, and particularly relates to the technical field of left auricle plugging, the left auricle plugging device comprises a plugging device body and a connector, the top end of the connector is provided with a signal supply module, and the signal supply module is located in the plugging device body; according to the left atrial appendage plugging device, after the inductor in the nut generates a voltage signal, the signal can be transmitted to the low-noise operational amplifier and amplified, meanwhile, the electromagnetic interference between the noise of a circuit and the outside world is restrained, and the plugging device can be used for plugging the left atrial appendage of the left atrial appendage of the left atrial appendage. The physical deformation is converted into corresponding electric signals, the electric signals are transmitted to an in-vitro receiving terminal through an antenna, and a doctor can indirectly judge the recovery condition of the atrial contraction function of the patient according to the pressure signal trend.

The invention discloses a method for effectively simulating general quantum computing based on a classical circuit network, and relates to the technical field of quantum computing simulation, and the method comprises the following specific steps: converting data into a voltage signal through input voltage coding, constructing a single-bit gate and a two-bit gate by using an operational amplifier and an analog multiplier, and constructing a single-bit gate and a two-bit gate; according to the invention, the general quantum computation is simulated by a classical circuit network, an n-bit unitary matrix is decomposed and reconstructed by means of input voltage coding quantum state and voucher / two-bit gate modular design, and the high-efficiency simulation of general quantum computation is realized. Quantum gate linear transformation is reproduced, quantum calculation universality is achieved, voltage signals and data are converted through a reflection formula, signal distortion is avoided, multi-level gate circuit cascading is supported, and a flexible and stable platform is provided for quantum algorithm verification and the like.

The invention discloses an environment-emotion gradient association memristive neural network circuit based on a TAP cell regulation mechanism. The environment-emotion gradient association memristive neural network circuit is composed of a hippocampus module and an amygdala kernel module. The hippocampus module comprises an environment recognition neuron module and an emotion generation neuron module; the environment recognition neuron module and the emotion generation neuron module are each composed of a weight regulation and control module adj based on a TAP cell regulation mechanism, an adder, a memristor, a resistor, an operational amplifier, a function module ABM1 and a sampling holder. Wherein the weight regulation and control module adj is composed of a voltage-controlled switch, a summator, a function module ABM2 and a function module ABM3. The almond kernel module is composed of a weight regulation and control module adj, a memristor, a resistor, an operational amplifier and a sampling holder. The provided circuit simulates the hippocampus and amygdala nucleus of the brain in structure, the regulation principle of TAP cells on neural stem cells is used for reference in a weight regulation mechanism, and bidirectional gradient associated memory of the environment and the emotion can be achieved.

The invention belongs to the technical field of analog integrated circuit design automation, and discloses an analog integrated circuit cross-process performance prediction method and system based on Transform transfer learning, and the method comprises the steps: 1, carrying out the preprocessing of analog integrated circuit sample data; 2, serializing the sample data according to a preset sequence, mapping each parameter into vector representation, adding a global abstract vector, and splicing according to a fixed sequence to form an input sequence; 3, encoding the input sequence to obtain an output sequence; 4, inputting the global features into the regression head network, and outputting a performance index prediction value; 5, training is carried out, network parameters obtained through pre-training of the source technology are migrated to the target technology, fine adjustment is carried out on part of network parameters of a target technology data set, and cross-technology performance prediction is achieved; and 6, performing forward reasoning on operational amplifier design parameters under a given target process according to the steps 2-4 to obtain a performance prediction result. The method improves the stability and efficiency of performance prediction.

The invention discloses an LDO (Low Dropout Regulator) circuit based on a level conversion and pre-adjustment module. The LDO circuit comprises a reference source, an error amplifier, a pre-adjustment module, a level conversion module, a power switch tube P1, a power circuit tube N1 and resistance feedback networks R1 and R2. The pre-adjustment module carries out voltage reduction processing on an input high-voltage power supply, and the level conversion module generates bias voltage according to an enable signal and the high-voltage power supply, controls a power switch and a switch in the operational amplifier, and ensures that the circuit is resistant to high voltage and extremely low in drain. The error amplifier adjusts the grid voltage of the power circuit according to the feedback and reference voltage difference value, and controls the current to stably output the voltage. And the resistance feedback network realizes closed-loop regulation of the output voltage. Under the condition that the LDO is enabled to be closed, the power tube can be ensured to be completely closed no matter the LDO is under the working voltage of 3V or 5V, so that the electric leakage condition of the LDO is greatly improved, and the LDO has the characteristic of low electric leakage.

The utility model provides a sampling circuit, an analog circuit and electronic equipment, and the sampling circuit comprises an input processing unit which is connected with the output end of a target circuit, and is used for collecting the common-mode output voltage of the target circuit, and carrying out the sampling input processing of the common-mode output voltage, and obtaining a first operational amplifier in-phase sampling signal and a first operational amplifier anti-phase sampling signal; the signal amplification unit is connected with the input processing unit and is used for respectively amplifying the first operational amplifier in-phase sampling signal and the first operational amplifier anti-phase sampling signal to obtain a second operational amplifier in-phase sampling signal and a second operational amplifier anti-phase sampling signal; and the signal stabilization unit is connected with the signal amplification unit and the control circuit, and is used for keeping the second operational amplifier in-phase sampling signal and the second operational amplifier anti-phase sampling signal, generating a feedback signal according to the second operational amplifier in-phase sampling signal and the second operational amplifier anti-phase sampling signal, and outputting the feedback signal to the control circuit. In this way, the input impedance and the sampling precision are improved.

The invention discloses a system reference clock frequency accuracy automatic calibration circuit and a calibration method thereof, and belongs to the technical field of frequency sources, the calibration circuit comprises a first crystal oscillator, a first power divider, a second power divider, a second crystal oscillator, an analog switch, a radio frequency switch, a detector, a comparator, an FPGA controller, a digital analog converter, an operational amplifier and a temperature sensor. When an external high-precision reference clock is accessed, the FPGA controller automatically switches a frequency measurement reference, performs high-precision frequency measurement on a 100MHz signal output by the first crystal oscillator, and judges whether calibration is needed or not according to frequency offset; if calibration is needed, the output voltage of the digital-to-analog converter is adjusted, the Vc end of the first crystal oscillator is controlled after operational amplification, and frequency closed-loop adjustment is achieved. According to the method, the crystal oscillator does not need to be disassembled, calibration is rapidly completed on site, and system availability and long-term frequency stability are remarkably improved.

The invention provides a power supply regulating device and a voltage-adjustable power supply circuit thereof, and relates to the technical field of power supply regulation, the circuit is additionally provided with a sampling resistor, an operational amplifier unit and an MCU on the basis of keeping the original sampling partial voltage, and adjustable analog level output by the MCU is injected into a DC-DC feedback pin after being subjected to operational amplifier gain, so that the voltage-adjustable power supply circuit is formed. The potential of a feedback node is biased in a voltage superposition mode, so that the output voltage and the analog level are in an approximately linear relation; according to the invention, higher resolution adjustment can be obtained in a preset full range only by changing the DAC level or the PWM duty ratio, the gear intervals are uniform, digital potentiometers or segmented switching are not needed, the calculation is simple, the hardware cost is low, and the control is convenient. The high-precision power supply can be widely applied to occasions requiring a software controllable high-precision power supply, such as a thermal printing head test fixture, ink-jet head ink quantity control, motor torque adjustment and the like. The invention aims to solve the problems that the resolution of a low-voltage section is suddenly reduced and the fineness is insufficient due to resistance-voltage nonlinearity during wide-range voltage regulation of a traditional digital potentiometer type DC-DC feedback network.

The invention relates to the technical field of current detection, and provides a multi-channel current time division multiplexing detection system and a current sampling chip. The system comprises a current sampling chip and a microcontroller. The current sampling chip is provided with a plurality of current sampling resistors, a plurality of current sampling signal switches, a logic unit and an operational amplifier module, and the plurality of current sampling signal switches are matched with the logic unit to switch current sampling voltage accessed to the operational amplifier module in a time division multiplexing mode, so that intensive detection of multi-channel current is realized; the overall scale of the system circuit is greatly reduced, and the hardware cost and the static power consumption are effectively reduced. Besides, a plurality of current sampling resistors and resistors in the operational amplifier module are arranged on the same chip in a matched manner, so that extremely high ratio consistency among the resistors is ensured, individual differences and mismatch errors caused by using a plurality of discrete devices are eliminated, and the accuracy of multi-channel current measurement is remarkably improved. And the consistency among the channels is particularly improved.

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 band-gap reference circuit, a working method thereof and electronic equipment, and relates to the technical field of band-gap reference circuits. The circuit comprises a pre-voltage-stabilizing module; the starting module is electrically connected with the pre-voltage-stabilizing module; the band gap core module is electrically connected with the starting module; the operational amplifier module is electrically connected with the band gap core module and the pre-voltage-stabilizing module; wherein the band-gap core module is used for outputting a reference voltage source; the pre-voltage-stabilizing module is used for buffering power supply voltage to obtain working voltage and providing the working voltage for the starting module and the operational amplifier module, and the pre-voltage-stabilizing module is further used for feeding back the influence of fluctuation of the power supply voltage on the reference voltage source to the pre-voltage-stabilizing module for readjustment; the starting module is used for starting the band gap core module; and the operational amplifier module is used for performing negative feedback regulation on the reference voltage source. The circuit can provide a reference voltage source with high PSRR and low temperature drift.

The invention provides a nanowatt-level voltage reference source circuit with low power supply voltage, which relates to the technical field of circuits and comprises a current bias module and a voltage reference generation module, the output end of the current bias module is connected with the bias end of the voltage reference generation module, and the current bias module is used for providing bias current with a high power supply rejection ratio; the voltage reference generation module comprises a first-stage operational amplifier and a second-stage operational amplifier, and the output end of the first-stage operational amplifier is connected to the input end of the second-stage operational amplifier; the first-stage operational amplifier is used for generating a threshold voltage difference value with a negative temperature coefficient; and the second-stage operational amplifier is used for performing temperature compensation on the threshold voltage difference value and outputting stable reference voltage. In the mode, nanowatt-level static power consumption under low power supply voltage is realized, the influence of process fluctuation is remarkably inhibited, and high-precision and low-temperature-drift reference voltage output is obtained.

The invention provides a reference voltage circuit and a DCDC converter, and relates to the technical field of semiconductors. The reference voltage circuit comprises a band-gap reference module and an operational amplifier module, the operational amplifier module is configured to enable the band-gap reference module to output initial reference voltage based on negative feedback operation, the operational amplifier module is configured with a first group of chopping switches, the band-gap reference module is configured with a second group of chopping switches, the first group of chopping switches has a first switching signal period, and the second group of chopping switches has a second switching signal period. The second group of chopping switches has a second switching signal period, and one of the first switching signal period and the second switching signal period is nested with the other one, so that error signals generated by the band-gap reference module and the operational amplifier module are reversely superposed; and the low-pass filtering module is configured to perform low-pass filtering on the initial reference voltage. According to the technical scheme, the reference voltage circuit meeting the requirement of a high-precision analog integrated circuit for the reference voltage can be obtained.

The invention discloses a non-intrusive voltage and current integrated monitoring device and method, and relates to the technical field of circuit measurement, the monitoring device comprises a probe circuit and a main control circuit, the probe circuit is integrated on a four-layer PCB, an operational amplifier, a Hall sensor and a peripheral circuit are placed on the uppermost layer of the four-layer PCB, the second layer is a grounding layer, and the main control circuit is connected with the probe circuit. The third layer is a negative electrode sensing plate, and the fourth layer is a positive electrode sensing plate; and the probe circuit acquires voltage by adopting a differential topological structure. When the monitoring device is used for measurement, the output voltage and current of the probe circuit are obtained according to the coupling capacitance of the three-phase cable, and the three-phase voltage and current are obtained by using the calibration matrix of the three-phase voltage and current. The device is small in size, a power system monitoring network is easy to establish, the method for monitoring the non-intrusive voltage and current through the device is easy to operate, and three-phase electricity can be monitored.

An electronic device may include a signal path that conveys a signal. The device may include an attenuator on the signal path that attenuates the signal. The attenuator may be free from series switches on the signal path. The attenuator may include a transmission line segment coupled in series between an input and an output of the attenuator. The transmission line segment may extend from a first terminal to a second terminal. A first adjustable resistance may couple the first terminal to ground. A second adjustable resistance may couple the second terminal to ground. The transmission line segment may have a length configured to perform impedance matching for the attenuator. A controller may control an attenuation level of the signal attenuator by adjusting the magnitude of the adjustable resistances. The controller may include a servo loop around an operational amplifier to mitigate process, voltage, and temperature variations in the attenuator.

The present disclosure provides a single-inductor multiple-output voltage converter, a power supply chip, and an electronic device, where the single-inductor multiple-output voltage converter comprises an energy generation circuit, an energy distribution circuit, a peak-inductor-current detection circuit, a zero-inductor-current detection circuit, and a control logic circuit. The aforementioned converter can provide multiple different output voltages using a single inductor without multiple operational amplifiers, thereby avoiding excessive bandwidth demand associated with multiple operational amplifiers, thus reducing power consumption.

The utility model relates to the technical field of dimming and color temperature switching, in particular to an IC chip and a multi-color-temperature switching circuit. A Flash storage module, a timer module, a first analog-to-digital conversion module, a second analog-to-digital conversion module, a third analog-to-digital conversion module, a processing module, a reference generation module, a comparator module, an operational amplifier AMP1, an operational amplifier AMP2, an MOS tube Q1 and an MOS tube Q2 are arranged in an IC chip, and a current setting pin and a first color temperature state setting pin are arranged on the IC chip. The second color temperature state setting pin, the third color temperature state setting pin, the power failure detection pin, the first LED current output pin and the second LED current output pin are matched together to realize the dimming and multi-color-temperature switching functions, so that the IC chip in the scheme can be compatible with the silicon controlled rectifier dimming function and also can realize multi-color-temperature switching.

Voltage regulating devices for organic light emitting diodes (OLED) are provided. The voltage regulating device includes an operational amplifier and a voltage output circuit. The operational amplifier generates an output voltage. The voltage output circuit is coupled to the operational amplifier. The voltage output circuit is controlled by a selection signal to generate a control voltage selectively using a first operating voltage interval or a second operating voltage interval. A voltage value of the control voltage is related to a reference voltage of the OLED, and the selection signal is correspondingly generated according to the reference voltage of the OLED.

The invention discloses a DAC output error correction method based on digital compensation, and the method comprises the steps: collecting the amplitude deviation, phase deviation and time sequence jitter data of a DAC output signal through a quantum sensing DAC calibration analysis platform, and constructing a multi-dimensional error original data set; calling an operational amplifier imbalance dynamic coupling prediction model to analyze a coupling relationship, and extracting dynamic association features; separating harmonic components and screening error contribution factors based on a broadband DAC harmonic distortion correction model; calculating a gradient change rule and an extreme point position by adopting a differential nonlinear gradient correction model; and integrating the characteristics and the parameters to construct a digital compensation parameter matrix, and dynamically adjusting an output code value through real-time digital modulation to realize error correction. According to the method, dynamic association and distribution characteristics of multi-source errors are accurately captured through multi-model collaborative operation and full-process closed-loop processing, multi-dimensional error synchronous correction is achieved, and DAC output precision and working condition adaptability are improved.

The invention discloses a clamping circuit of an error amplifier, which belongs to the field of analog integrated circuits and comprises an error amplifier EA, a low-voltage clamping circuit and a high-voltage clamping circuit. The error amplifier EA comprises a first-stage operational amplifier, the non-inverting input end of the first-stage operational amplifier is connected with feedback voltage VFB, the inverting input end of the first-stage operational amplifier is connected with reference voltage VREF, and the first-stage operational amplifier outputs VC voltage; the error amplifier EA is used for amplifying the change of the feedback voltage VFB; when the VFB is reduced or increased, the corresponding low-voltage clamping circuit or the high-voltage clamping circuit works, the output VC of the first-stage operational amplifier is clamped to the low-voltage clamping limit VclampL or the high-voltage clamping limit VclampH, the VC is controlled to be within a certain range, then clamping of the output current IEA of the error amplifier EA is achieved, quick response and stable adjustment of a loop are achieved, and meanwhile the function of protecting the circuit is achieved.

The invention belongs to the technical field of stability compensation circuits, and particularly relates to a stability compensation circuit structure of a high-speed operational amplifier, which is characterized by comprising a function module, a first control module, a second control module, a third control module, a fourth control module and a fourth control module, and the function module comprises an input stage, a differential common-base gain stage, a common-base level converter module and an output stage, and the stability compensation assembly comprises a dual-frequency load unit which is matched with the functional module and comprises a low-frequency load branch and a high-frequency load branch which are connected in parallel. Through the synergistic effect of the double-frequency load unit and the pole regulation and control capacitor, gain segmentation regulation and control of low-frequency high gain and high-frequency fast attenuation are achieved, the open-loop gain of the operational amplifier breaks through the limitation of 30dB of an existing HBT single-stage operational amplifier, and meanwhile the problem that high-frequency phase shift changes too fast is effectively restrained; through simulation verification, the phase margin can reach 67 degrees, the stability requirement of 45-60 degrees and above of an analog circuit is met, and the core contradiction that the high-gain bandwidth and the phase margin of an HBT device are difficult to balance is thoroughly overcome.

The invention discloses a pixel unit circuit for a dynamic vision sensor. The pixel unit circuit comprises a photodiode, an IV conversion circuit, a switched capacitor amplifier, a comparison circuit and a pixel readout logic circuit, the switched capacitor amplifier comprises a first capacitor, a second capacitor, an operational amplifier and a reset switch tube, the first capacitor is connected between the output end of the IV conversion circuit and the inverted input end of the operational amplifier, the in-phase input end of the operational amplifier is connected with a reference power supply, and the output end of the operational amplifier serves as the output end of the switched capacitor amplifier; the operational amplifier is connected with the comparison circuit, the second capacitor is connected between the inverted input end and the output end of the operational amplifier, the drain electrode and the source electrode of the reset switch tube are connected with the inverted input end and the output end of the operational amplifier respectively, and the substrate of the reset switch tube is connected with the output end of the switched capacitor amplifier; the comparison circuit is used for outputting event signals; and the pixel read-out logic circuit is used for reading out the event signal and is connected with the grid electrode of the reset switch tube.

Embodiments described herein are directed to a position sensor that includes a first receiver coil electrically coupled to a first multiplier to generate a first output, a second receiver coil electrically coupled to a second multiplier to generate a second output, a transmitter coil electrically coupled to an oscillator, the oscillator electrically coupled to a third multiplier to generate a third output, a phase-locked loop electrically coupled to the oscillator and the transmitter coil, a summing circuit configured to receive the first output and the second output and configured to generate a signal, a phase detector configured to receive the signal and the third output, the phase detector outputting a sense signal that is indicative of an angle of the motor position sensor, and a pair of op amps electrically coupled to the phase detector. The op amps configured to output an analog differential signal and a differential phase signal.

The invention provides a picoampere-level current measuring device and method with leakage estimation and digital compensation, and the device comprises an electrometer-level operational amplifier and a transimpedance feedback network which are used for converting a measured current into a voltage signal; in combination with a retaining ring conductor driven by a retaining ring buffer and an inner and outer double-layer metal shielding structure, high-resistance node leakage and external interference are remarkably reduced. The digital controller injects 5mV-50mV micro excitation into the retaining ring in a non-sampling window and detects output response so as to estimate input equivalent leakage conductance and perform online compensation; and meanwhile, environment self-adaptive correction is carried out according to a temperature and humidity-leakage admittance model. The system adopts a 24-bit analog-to-digital converter, two-stage zero-drift amplification and multi-point linearity calibration can be switched, picoampere-level current measurement with high precision, low noise and wide dynamic range is realized, and the system is suitable for the fields of high-insulation detection, light current measurement, electrochemical micro-current analysis and the like.

The invention relates to the technical field of charging control, and discloses a charging current control circuit, an energy storage device and a battery management system, the circuit comprises a reference source unit, the input end of the reference source unit is connected with an external power supply port, the reference source unit is used for receiving the input voltage of the external power supply port, and the input voltage of the external power supply port is output to the energy storage device; a reference voltage is generated based on the input voltage; the input end of the operational amplifier chip unit is connected with the output end of the reference source unit and the current input port of the energy storage device, and the operational amplifier chip unit is used for receiving the input current of the current input port and generating an input control signal based on the input current and the reference voltage; and the input end of the pulse width modulation chip is connected with the output end of the operational amplifier chip unit, and the pulse width modulation chip is used for performing charging current control based on the input control signal. The accuracy of the charging current control circuit is improved.

An audio amplifier that implements current mode control without the use of an explicit or separate current mode sensor is disclosed. The audio amplifier may include a pair of feedback loops that provide current from a node located before an inductor of an output filter and current from a node located after the inductor of the output filter to an integrator circuit. The integrator circuit may be formed from existing circuitry of the audio amplifier controller. Thus, current mode control can be implemented without a separate current mode sensor. Further, the audio amplifier can be implemented as a half bridge or as a full bridge design without increasing the number of operational amplifiers compared to the half bridge.