414 results about "Differential amplifier" patented technology

A Rydberg atom television receiver is disclosed. The receiver comprises a probe laser, a source polarizing beam displacer, a Rydberg atom receiver cell, receiver atoms, a detector polarizing beam displacer, a detector polarizing beam cube, a first photodiode, a second photodiode, a differential amplifier, a display, and a coupling laser. The receiver receives a modulated waveform imprinted on a radiofrequency carrier a displays a graphical representation corresponding to a modulation source.

The invention discloses a sensor array acquisition system for detecting gas, and relates to the field of gas sensors. The sensor array acquisition system for detecting gas comprises a gas sensor array, a signal conditioning circuit, an analog-to-digital conversion module, a control module and a power supply module. According to the sensor array acquisition system for detecting the gas, the voltage follower circuit with high input impedance is adopted, so that the problem of attenuation during signal acquisition of a high-impedance sensor is effectively solved, and the signal acquisition precision is improved. Through the adjustable direct-current bias circuit and the differential amplification circuit, the dynamic adjustment of the measurement range is realized, the gas detection requirements of different concentration ranges can be met, and hardware does not need to be replaced. A constant-current driving chip is adopted to control a sensor heating circuit, heating current can be accurately set by adjusting external resistance, it is ensured that the sensor works at the optimal temperature, and the stability and response speed of the sensor are improved.

A monitoring device is provided. The monitoring device comprises one or more circuitry operable to obtain measurements of one or more pins of a battery system, the one or more circuitry comprising at least one circuit for monitoring current, which comprise: at least one other circuit for amplifying variance comprising at least one differential amplifier, one voltage reference in electrical connection with a first input of the differential amplifier; at least one transconductance means comprising at least one output in electrical connection with a second input of the differential amplifier and at least one input in electrical connection with an output of the differential amplifier; at least one current source in electrical connection with at least one output of the at least one transconductance means; and an output in electrical connection with at least one output of the at least one transconductance means.

The invention discloses an automatic temperature compensation circuit and method based on a thermal flowmeter, and relates to the technical field of temperature compensation, and the compensation circuit comprises a constant current source module used for driving the thermal flowmeter; the Wheatstone virtual bridge arm is used for acquiring a changed digital-to-analog converter output voltage value output by the controller, and performing voltage conversion on a first voltage and a second voltage which are output on the thermal flowmeter due to the change of the external temperature according to the output voltage value to obtain a third voltage; the digital-to-analog converter is used for performing correction compensation on the third voltage according to the correction compensation value calculated by the controller; and the differential amplification module adopts a differential amplifier to amplify the third voltage and the fourth voltage output by the thermal flowmeter, and outputs a compensated flow signal. The compensating circuit is simple in structure and higher in reliability and precision, and compared with a digital potentiometer, the output value of the Wheatstone virtual bridge arm is changed by using the output value of the digital-to-analog converter, so that the adjusting resolution is higher.

The invention relates to the technical field of electric field detection and early warning. The invention aims to overcome the defect of lack of an electric field detection device under the hot-line working condition of an ultra-high-voltage line in the prior art, and relates to an electric field detection device under the hot-line working condition of the ultra-high-voltage line, which is a non-contact electric field detection device and is used for detecting the electric field under the hot-line working condition of the ultra-high-voltage line in the hot-line working condition of the ultra-high-voltage line. The non-contact electric field detection device takes a microprocessor as a core control unit, and is composed of a double-spherical-shell type electric field sensor, a differential amplifier, a filter circuit, a true RMS conversion circuit, a power supply module and a man-machine interaction circuit. And deep association of data support, function collaboration and scene adaptation is carried out through the structure. The problem that traditional equipment is insufficient in stability in a severe environment is solved, continuous and stable operation of the electric field detection equipment under complex working conditions is achieved, it is ensured that reliable electric field intensity data can be continuously output, and a basic guarantee is provided for operation safety evaluation.

The ultralow frequency sensor comprises a vibration detection unit, a power supply voltage stabilization unit and a signal conditioning unit, the power supply voltage stabilization unit is provided with a low dropout linear voltage regulator U20, a voltage converter U19 and a negative voltage regulator U21, and the low dropout linear voltage regulator U20 stabilizes an external power supply as a positive power supply VCC; the voltage converter U19 is used for converting positive voltage of an external power supply into negative voltage and outputting stable negative power supply VEE through the negative voltage stabilizer; the positive power supply VCC and the negative power supply VEE supply power to the signal conditioning unit; the signal conditioning unit comprises a high common mode rejection differential amplifier, a differential-to-single-ended amplifier, a band-pass filter and a differential output driver, a differential signal output by the vibration detection unit sequentially passes through the high common mode rejection differential amplifier, the differential-to-single-ended amplifier, the band-pass filter and the differential output driver, and then a differential voltage signal is output; the method has the advantages of high stability and reliability and the like.

The invention relates to the technical field of switching power supply, and discloses a switching power supply constant-current protection circuit and a protection method thereof.The switching power supply constant-current protection circuit comprises an environmental parameter sensing module which collects current signals of a constant-current output loop through a shunt resistor and a differential amplifier, collects input voltage through a resistance voltage-dividing network and collects temperature through a thermistor; the dynamic threshold value generation module is used for receiving the current signal and the environment parameter and generating a dynamic current protection threshold value to maintain constant current output; the AI prediction protection module is used for sampling current signals, extracting high-frequency energy characteristics through frequency domain analysis and comparing the high-frequency energy characteristics with a dynamic current protection threshold value; a digital twin monitoring module; and a protection execution module. Temperature parameters are collected in real time, polynomial fitting calculation is executed, the nonlinear characteristic of a thermistor is converted into a linear compensation coefficient, a protection threshold value is dynamically generated in combination with a current effective value and input voltage fluctuation, and self-adaptive drift compensation of a constant-current protection point in a full temperature range is achieved.

The invention relates to the technical field of detection circuits suitable for various electricity utilization information acquisition terminals, and discloses a detection circuit method suitable for various electricity utilization information acquisition terminals. The method comprises the following steps: setting an environment temperature, calibrating a shunt resistor and a thermistor, constructing a three-order resistance-temperature mapping relation, and calculating thermal resistance and thermal response characteristics to realize accurate modeling; a thermistor is attached to a shunt resistor, heat-conducting silicone grease is added to form a thermal coupling structure, voltage is collected through a constant current source and a differential amplifier, a resistance value is converted into temperature in real time, instantaneous current is inversely calculated based on a heat balance equation, then energy integration and grade judgment is completed, and various electrical parameter indexes are output. According to the method, modeling, collection, conversion and inversion processes are integrated, a complete thermal-electric detection link is constructed, a traditional current sensor is not needed, and the method has the advantages of being compact in structure, low in cost, flexible in deployment and the like and is suitable for a low-power-consumption distributed terminal.

Disclosed is a two-stage successive approximation register analog to digital converter based on a difference and differential amplifier, including a first-stage sub-ADC, a difference and differential amplifier, and a second-stage sub-ADC connected in sequence. The first-stage sub-ADC and the second-stage sub-ADC each include capacitor arrays and comparators. The difference and differential amplifier includes a transconductance amplifier GM1, a transconductance amplifier GM2, a resistance load R, and proportional resistors R1 and R2. The transconductance amplifier GM1, the resistance load R, and the transconductance amplifier GM2 form a negative feedback loop. The disclosure adjusts the gain of the amplifiers through the proportional resistors R1 and R2, so that higher conversion accuracy can be achieved.

A comparator is disclosed. The comparator includes an amplifier circuit, a latch circuit, and a boost circuit. The amplifier is configured to amplify a difference between the first and second differential inputs during an active phase of the comparator. The latch circuit includes first and second transistors, respectively coupled to first and second differential amplifier outputs, and configured to respectively drive first and second legs of the latch circuit during the active phase. The boost circuit includes first and second boost transistors respectively coupled to the first and second differential amplifier outputs, and configured to respectively provide a first supplemental current to the first differential output of the latch circuit and a second supplemental current to the second differential output of the latch circuit.

Amplifiers incorporating equalizer and bias offset correction circuits are described. An example amplifier circuit with equalizer and bias offset correction includes an amplifier with an input, an equalizer circuit coupled to the input of the amplifier, and a bias offset correction circuit coupled to the input of the amplifier. The bias offset correction circuit is configured to adjust a bias potential at the input of the amplifier. In one example, the amplifier is a differential amplifier with differential inputs, the equalizer circuit is coupled to the differential inputs of the amplifier and is configured to adjustably modify a gain of the amplifier over frequency, and the bias offset correction circuit is coupled to the differential inputs of the amplifier and is configured to compensate for modifications to bias potentials at the differential inputs of the amplifier due to operation of the equalizer circuit.

The invention relates to the technical field of photoelectric detection, and provides a single-photon counter circuit for weak light detection based on a photomultiplier, and the single-photon counter comprises a photoelectric conversion circuit, a differential amplification circuit, a threshold comparison circuit and a signal shaping circuit. The photoelectric conversion circuit is composed of a photomultiplier, a high-voltage power supply circuit and a voltage division circuit, detects weak light signals and outputs two paths of current signals through photoelectric conversion. The differential amplification circuit carries out differential amplification on the two current signals through a differential amplifier. The threshold comparison circuit compares two input signals, filters out signals with the amplitude lower than 1 / 2 of a set threshold, and outputs a single-path effective signal. And the signal shaping circuit shapes the effective signal and finally outputs the effective signal in a TTL pulse mode. According to the single photon counter circuit for weak light detection, the background dark counting rate is low, the sensitivity is high, and the counting unit module specially used for digital pulse statistics is connected behind the single photon counter circuit for counting single photons.

A dynamic vision sensor (DVS) system includes a pixel array composed of a plurality of pixels; a multi-channel differential amplifier composed of a plurality of differential amplifiers coupled to respectively receive plural pairs of pixel signals from one or more frames read out of the pixel array, thereby generating a plurality of difference signals respectively; a multi-channel comparator composed of a plurality of comparators configured to respectively compare the difference signals with a predetermined threshold, thereby generating a plurality of flags respectively; and an event detection circuit that generates an event signal according to the flags.

An electronic circuit comprising a first transistor coupled between a voltage supply and a first node, a second transistor coupled between the voltage supply and a second node, and a differential amplifier comprising first and second input terminals and an output terminal. The differential amplifier is coupled to an input terminal of the first transistor and to an input terminal of the second transistor. The first node is coupled to the first input terminal of the differential amplifier. The second node is coupled to the second input terminal of the differential amplifier.

Various embodiments of the invention provide for an AC-coupling method and systems that utilize a nested loop circuit to generate a differential mode output that facilitates an offset compensation and a common mode output that facilitates DC-biasing of an active circuit. In embodiments, the nested loop circuit comprises a differential amplifier and a differential mode loop that generates a differential mode output and a common mode loop that uses a common mode voltage and a reference voltage to generate the common mode output.

This invention belongs to the field of wireless communication technology. It provides a differential amplifier system and a method for improving common-mode stability. The invention uses a large decoupling capacitor C1 at the transformer center tap to provide AC ground, and a common-mode resistor R1 to improve the circuit's common-mode stability. Since the common-mode resistor R1 is not in the differential signal loop path, the use of common-mode resistor technology does not affect differential-mode performance. Because the required common-mode resistor value is small, this design occupies a small layout area. This invention solves the problem of low common-mode stability in differential amplifiers.

Embodiments include herein are directed towards a circuit having a core bandgap reference circuit including a first transistor, a second transistor, and a differential amplifier. The circuit may further include a cascoded bandgap reference circuit in electrical communication with the core bandgap reference circuit, wherein the cascoded bandgap reference circuit includes a first supply noise path that includes a plurality of transistors that are electrically connected and a flipped voltage follower configuration that reduces an impedance at a transistor associated with a second supply noise path.

The techniques described herein relate to a circuit including an operational amplifier that includes a differential amplifier, a capacitor, and an output stage. The differential amplifier includes a first input and a second input. The output stage is configured to generate an output voltage. The circuit includes a slew-rate boost circuitry connected to the operational amplifier. The slew-rate boost circuitry is configured to detect a voltage differential between the first input and the second input and apply, at an output of the differential amplifier, a boost current to charge the capacitor during a period of time in which the output voltage increases or decreases to a target voltage level.

A fully differential amplifier is provided, comprising one or more stages and a class AB output stage. The one or more stages amplify a differential pair of input signals to produce an amplified differential pair of signals, and the class AB output stage further amplifies the amplified differential pair of signals to produce a differential pair of output signals. The class AB output stage includes a pair of differential outputs. For each of the differential outputs, the class AB output stage includes a folded network of transistors and a feedback circuit. Transistors in the folded network form a control amplifier for regulating the control inputs of the output pair, and the feedback circuit controls this control amplifier. The folded network biases a pair of output transistors in class AB.

To facilitate gain adjustment of a differential amplifier circuit while reducing the impact of pattern inductance between a buffer and the differential amplifier circuit.SOLUTION: A differential amplifier 110 includes: a pair of buffers to which separate signals are input; a first differential amplifier circuit 101 for amplifying a difference between output signals from the pair of buffers; a second differential amplifier circuit 102 for amplifying the difference between the output signals from the pair of buffers with a polarity opposite to the first differential amplifier circuit 101; a third differential amplifier circuit 103 for amplifying the difference between the output signals from the first differential amplifier circuit 101 and the second differential amplifier circuit 102; and damping resistors connected between each of branch points at which the output signals from the pair of buffers branch and each of the first differential amplifier circuit 101 and the second differential amplifier circuit 102.SELECTED DRAWING: Figure 5

The application discloses a kind of control circuit and method of server standby power supply, including main power drive unit, analog PI regulator, current sampling conditioning circuit and OringFET tube;Main power MOS tube realizes main loop on-off control, and triode is used to change the gate voltage of main power MOS tube to control its conduction, cut-off;Analog PI regulator is composed of reference source and operational amplifier, reference source provides accurate reference voltage, and operational amplifier compares and adjusts current detection signal with reference voltage, dynamically corrects the control level signal of output, and then controls the on-off of main power MOS tube through driving circuit;Current sampling conditioning circuit includes sampling resistance and differential amplifier, and real-time acquisition main loop current is converted into identifiable voltage signal, to provide accurate data support for analog PI regulator.The application is applied when server is in shutdown state, and can be remotely executed by network to start, restart, install operating system or monitor hardware health state and the like operation.

The application discloses to the technical field of differential amplifier, specifically a differential amplifier circuit with high common-mode input voltage, comprising: an internal differential amplification circuit for processing input signals; a power supply voltage detection module for detecting an external power supply voltage for powering the circuit and outputting a detection signal; a charge pump module for boosting the external power supply voltage to generate a boosted power supply; a control module coupled with the power supply voltage detection module and the charge pump module respectively for receiving the detection signal and controlling the working state of the charge pump module based on the detection signal; based on this, the application has the effect of enabling the chip to maintain high common-mode input voltage processing capability and high common-mode rejection ratio within the full power supply voltage range, and can stably process high common-mode signals without relying on a specific numerical high-voltage power supply, solving the problem of sharp performance decay under low power supply voltage in the prior art.

The invention discloses a tumor detection device and method based on a diamond quantum sensor, and belongs to the technical field of biomedical detection. The device comprises an optical fiber laser, an optical fiber beam splitter, an optical fiber attenuator, an optical fiber circulator, an optical filter, two photoelectric detectors, a differential amplifier, an electronic filter, a computer, a signal generator, two microwave antennas and an optical fiber probe. The optical fiber probe comprises an optical fiber packaged in a plastic shell, a diamond quantum sensor which is fixed at the tail end of the optical fiber and comprises an NV color center, and a first microwave antenna integrated beside the optical fiber. The laser excites the diamond to generate fluorescence, meanwhile, the signal generator drives the two microwave antennas to apply a microwave field, and the dielectric property of the sample to be detected modulates the fluorescence intensity of the diamond by influencing the microwave field. Laser noise is eliminated through a differential amplification and filtering technology, and fluorescence signal change is analyzed by a computer, so that dielectric constant distribution of a sample is reconstructed, and non-invasive and high-sensitivity detection of tumors is realized.

The utility model discloses a kind of OS test switching PCB with four-wire system precision resistance measurement, including PCB substrate, OS test signal switching module, four-wire system resistance measurement module, relay switching unit, ADC measurement circuit and I2C communication interface.OS test signal switching module is docked OS tester, realize conducting and insulation test.Four-wire system resistance measurement module adopts constant-current source and four-wire system kelvin measurement mode, rely on differential amplifier circuit and high-precision ADC, complete 0.1Ω~40Ω small resistance precision measurement.Relay switching unit realizes two types of test path interlock switching and electrical isolation, and prevents signal mutual interference.The utility model integrates conducting test switching and precision resistance measurement function, compact structure, high measurement accuracy, good isolation, can realize DUT framework and ground end resistance on-line automation detection, adapt OS test system, effectively improve test efficiency and operation reliability.

This invention proposes a dual-resonance coherent population trapping magnetometer and its implementation method, which can effectively suppress optical noise of lasers, improve sensitivity, and increase the lower limit of the measurement range. It includes: a first microwave source, a second microwave source, a first current source, a second current source, a first bias-T, a second bias-T, a first VCSEL laser, a second VCSEL laser, a first collimating lens, a second collimating lens, a first PBS, and a λ / 2 waveplate. 87 The system includes an Rb atom gas cell, a second PBS, a first photodiode, a second photodiode, a differential amplifier, and a dual-channel lock-in amplifier. The first VCSEL laser, the second VCSEL laser, the first collimating lens, the second collimating lens, the first PBS, and the λ / 2 waveplate are located at... 87 On the left side of the Rb atomic gas cell, the first VCSEL laser and the first collimating lens are located to the left of the first PBS, and the second VCSEL laser and the second collimating lens are located below the first PBS. The laser output from the second VCSEL laser is reflected by the first PBS and propagates towards the right atomic gas cell.

The present application relates to the technical fields of dynamic reverse bias test, and relates to a circuit and a method for detecting dynamic leakage current in dynamic reverse bias of silicon carbide power devices, the circuit comprises a circuit for detecting dynamic leakage current in dynamic reverse bias of silicon carbide power devices, including a gate resistor, a half-bridge topology circuit, a Schottky barrier diode, a differential amplifier and a direct current power supply, the half-bridge topology circuit comprises an upper bridge auxiliary measurement silicon carbide power device, a lower bridge measured sample and a lower bridge sampling resistor, the gate of the auxiliary measurement silicon carbide power device and the gate of the measured sample are respectively connected with a gate drive input signal through the gate resistor; a plurality of Schottky barrier diodes are connected in parallel with the lower bridge sampling resistor to form an active low-pass filter, the non-inverting input and the inverting input of the differential amplifier are respectively connected with the anode and the cathode of the Schottky barrier diode; the present application can effectively filter out current spikes, solve the problem of related high dV / dt current spikes, and ensure the high precision of the leakage current monitoring signal.

Disclosed is a semiconductor integrated circuit device including: a switching transistor; a terminal to receive a control signal from outside; and a control circuit that controls the switching transistor based on the control signal. The control circuit includes: a reference voltage source that generates a reference voltage from the DC voltage; a differential amplifier to receive the reference voltage and a voltage of the voltage output terminal, and output a voltage applied to a control terminal of the switching transistor; and a logic circuit that generates a signal to control an operation state of the differential amplifier based on the control signal. According to an output signal of the logic circuit, the differential amplifier controls the switching transistor to be on in response to the control signal being a first logic level, and to be off in response to the control signal being a second logic level.

The invention discloses a crawler-type pipeline detection device and method based on a magnetic eddy current principle, and belongs to the technical field of pipeline defect detection.The crawler-type pipeline detection device comprises a crawler-type moving vehicle, a detection module, a detection module and a control module, and the crawler-type moving vehicle is provided with a power source and electrically connected with the power source; the camera is arranged at the upper end of the crawler-type mobile vehicle; the camera is electrically connected with the power supply and the control module; the magnetic eddy current probe is arranged at the front end of the advancing direction of the crawler-type mobile vehicle and is electrically connected with the power supply and the control module; the magnetic eddy current probe comprises three detection coils, one detection coil is a central excitation coil, and the other two detection coils are differential receiving coils; the center excitation coil is connected to the output end of the signal generator through a signal excitation line, the two differential receiving coils are connected to the input end of the differential amplifier through signal receiving lines, and the whole circuit is connected to the control module. According to the invention, real-time image transmission, dotting positioning, video monitoring, data acquisition, small crack detection and effective early warning can be carried out, and various defects of manual detection are avoided.

The oscillation circuit 1 comprises: an oscillator X1; a first capacitance CF having one end connected to the oscillator X1; a second capacitance CO having one end connected to the other end of the first capacitance CF; an output terminal Vo connected to a connection point N2 of the first capacitance CF and the second capacitance CO; an amplifier circuit A1 connected between a node between the oscillator X1 and the first capacitance CF and a connection point N2 of the first capacitance CF and the second capacitance CO to form an oscillation loop together with the first capacitance CF; a differential amplifier circuit A2 arranged on the oscillation loop; and a feedback path 3 configured to feed a part of an output on the output terminal Vo to the differential amplifier circuit A2.

In described examples, a low dropout voltage regulator includes an input voltage terminal, a resistive element, first and second transistors, an output terminal, a differential amplifier, and first and second saturation prevention circuits. The resistive element is coupled between the input voltage terminal and a gate of the first transistor. The output terminal is coupled to the drain of the first transistor and the source of the second transistor. A first input of the differential amplifier receives a reference voltage, and a second input is coupled to the output terminal. The first saturation prevention circuit provides a first clamp current to the differential amplifier output if the gate-source voltage of the first transistor is less than a first threshold voltage. The second saturation prevention circuit provides a second clamp current to the differential amplifier output if the gate-source voltage of the second transistor is greater than a second threshold voltage.