119 results about "Instrumentation amplifier" patented technology

The invention discloses an output voltage detection method and system based on an aviation power supply, and relates to the technical field of aviation power supply voltage detection. A differential voltage sensor is connected to the output end of an aviation power supply, a high-frequency suppression capacitor is connected in parallel, the sampling rate of 20-50 times of the working frequency is set according to the type of the power supply, and the signals are collected and converted into analog voltage signals; the analog signal is subjected to two-stage filtering, is amplified to 0-5V through an instrument amplifier, and is converted into a digital voltage sequence through a 16-bit ADC (Analog to Digital Converter); calculating AC power supply effective value, peak value and other parameters, DC power supply average value, ripple coefficient and other parameters; comparing the characteristic parameters with a preset threshold value, determining that the characteristic parameters exceed the threshold value and recording related information; and a detection result is transmitted to a monitoring terminal through an RS485, data is locally stored, and a switching value is output to an alarm device when the data is abnormal. The method adapts to aviation power supply load fluctuation and environment temperature change, detection precision is high, data transmission and storage are safe, abnormity is accurately identified and early warning is carried out in advance, and aviation power supply operation and maintenance reliability and efficiency are improved.

The various implementations described herein include techniques and apparatuses for multi-channel biopotential signal acquisition, biopotential signal pre-processing, and adaptive signal conditioning. In one aspect, an analog frontend circuit includes an instrumentation amplifier (INA) and an analog-to-digital circuit (ADC) in a forward signal path. A digital circuit receives input from the ADC. An adaptive baseline tracking and compensation circuit tracks and compensates moving motion artifact driven changes. A power line interference (PLI) detection and compensation circuit tracks a desired number of PLI harmonics, and magnitude, phase and frequency for the PLI harmonics in real time. A digital-to-analog converter (DAC) circuit combines output of the adaptive baseline tracking and compensation circuit and the PLI detection and compensation circuit to output an analog output. A passive filter receives the analog output and drives an analog compensation signal at an input of the INA.

The invention relates to the technical field of power grid measurement, in particular to a miniaturized wireless self-powered alternating current electric field measurement method and system. Comprising the following steps: acquiring radio frequency energy in an electric field environment, and converting the radio frequency energy into direct current electric energy through a radio frequency energy acquisition system consisting of a microstrip antenna, a voltage doubling rectifying circuit and an energy management circuit; an alternating current electric field signal is collected through a differential dual-electrode sensor structure, and an electric field voltage signal is generated; amplifying the voltage signal through an instrument amplifier, and obtaining a digital signal of the electric field signal through an analog-to-digital conversion circuit; and processing and analyzing the alternating current electric field information according to the digital signal. By combining a radio frequency energy acquisition technology with a differential dual-electrode sensing structure, the electric field sensor has the performance characteristics of self energy supply, miniaturization, high precision, wide frequency response and low power consumption. The system can measure various types of electric field signals, including sine wave, triangular wave and square wave electric field signals, has a wide frequency range and a wide measuring range, and is excellent in linearity.

The invention relates to the technical field of amplifiers, and discloses an analog-to-digital converter combination instrument amplifier which comprises a first-stage amplifier, the first-stage amplifier is in signal connection with a second-stage amplifier, the second-stage amplifier is in signal connection with a front-end low-pass filter (LPF), the front-end low-pass filter (LPF) is in signal connection with an analog-to-digital converter (ADC), and the analog-to-digital converter (ADC) is in signal connection with the analog-to-digital converter. And an unbalanced input-to-balanced differential circuit output module is arranged between the second-stage amplifier signal and a front-end low-pass filter (LPF). From the perspective of signal processing and conversion, a precise signal transition bridge is constructed by adding an unbalanced input-to-balanced differential circuit output module, unbalanced signals output by a second-stage amplifier are converted into double-end balanced differential signals, common-mode noise interference is effectively resisted through a differential transmission mode, the signal purity is guaranteed, and the signal quality is improved. The front-end low-pass filter and the analog-to-digital converter are adaptive to differential signals, so that the signal transmission is stable and anti-interference, and the analog-to-digital conversion is more accurate.

The invention provides a frequency converter embedded current waveform analysis method and system and a medium, and relates to the technical field of current waveform analysis, and the method comprises the steps: obtaining a sampling circuit configured in a current path of a frequency converter; calculating the required total gain based on the original output voltage signal of the sampling resistor and the required input voltage of the analog-to-digital converter; the signal quality of the original output voltage signal is evaluated, the required total gain is dynamically distributed to an instrument amplifier and a programmable gain amplifier, the original output voltage signal is amplified and then passes through an analog-to-digital converter, and current waveform data is obtained for current anomaly analysis; when the signal quality is lower than a first threshold value, the gain share of the instrument amplifier is increased preferentially; when the signal quality is higher than a second threshold, the gain share of the programmable gain amplifier is increased preferentially. According to the invention, the technical problem of low accuracy of current waveform analysis in the prior art can be solved, and the technical effect of improving the accuracy of waveform analysis is achieved.

The various implementations described herein include techniques and apparatuses for multi-channel biopotential signal acquisition, biopotential signal pre-processing, and adaptive signal conditioning. In one aspect, an analog frontend circuit includes an instrumentation amplifier (INA) and an analog-to-digital circuit (ADC) in a forward signal path. A digital circuit receives input from the ADC. An adaptive baseline tracking and compensation circuit tracks and compensates moving motion artifact driven changes. A power line interference (PLI) detection and compensation circuit tracks a desired number of PLI harmonics, and magnitude, phase and frequency for the PLI harmonics in real time. A digital-to-analog converter (DAC) circuit combines output of the adaptive baseline tracking and compensation circuit and the PLI detection and compensation circuit to output an analog output. A passive filter receives the analog output and drives an analog compensation signal at an input of the INA.

The invention belongs to the related technical field of industrial displacement measurement, and discloses a half-bridge strain gauge displacement sensor signal conditioning circuit which comprises a half-bridge Wheatstone circuit module with manual zero setting, an RFI filtering module, a primary instrument operational amplifier module, a secondary precision amplifier module, an RC filtering module and a reverse following module which are sequentially connected in series. The half-bridge Wheatstone circuit module comprises a manual zero setting half-bridge Wheatstone circuit module and is used for dynamically compensating millivolt-level offset voltage caused by tolerance of a strain gauge and a fixed-value resistor; the RFI filtering module is used for suppressing rectification errors caused by radio frequency interference; the RC filtering module is used for suppressing high-frequency noise and smoothing a signal waveform; the reverse following module is used for realizing impedance isolation; two resistors are connected into a half-bridge Wheatstone circuit to form a manual zero setting module, millivolt-level offset voltage caused by tolerance of a strain gauge and a fixed-value resistor is dynamically compensated, and the problem that a traditional bridge sensor is insufficient in offset voltage and signal-to-noise ratio is solved.

The invention relates to the technical field of measurement of long-distance and high-accuracy temperature measurement resistors, and particularly discloses a resistor temperature measurement method, which comprises a constant current source I, temperature measurement resistors RX and RY, a reference resistor RR, an analog switch, an instrument amplifier, an analog-to-digital converter and a microcontroller, the method comprises the following specific steps that S1, an analog switch controls a constant current source I to sequentially flow through temperature measurement resistors RX and RY and a reference resistor RR, and current generates a voltage on each resistor and is in direct proportion to the resistance value of the voltage; and S2, measuring the voltages of the temperature measuring resistors RX and RY and the reference resistor RR through an instrument amplifier and an analog-to-digital converter to obtain VX1, the voltage of the temperature measuring resistor RX under the forward current condition, VY1, the voltage of the temperature measuring resistor RY under the forward current condition, and VR1, the voltage of the temperature measuring resistor RR under the forward current condition. According to the resistance temperature measurement method, 0.00025 DEG C or better uncertainty can be obtained, and observable errors caused by thermoelectromotive force can be effectively eliminated.

The application discloses a kind of multi-modal flexible sensor adaptive signal conditioning system design method, belong to flexible sensor signal conditioning technical field.The present application overcomes the defects of poor universality, performance compromise, high cost of mass production of existing conditioning circuit, adopts layered decoupling and dynamic reconstruction system-level architecture: through multi-modal feature analysis and demand mapping modeling, the feature vector composition of scene recognition is determined;Design configurable analog front end, integrate instrument amplifier, transimpedance amplifier, charge amplifier, bridge amplifier four parallel processing sub-modules, wherein charge and bridge amplifier adopt self-designed architecture with dynamic adaptive gain adjustment capability;Build heterogeneous digital processing platform with NPU, CPU, DSP as core, through cross-modal data fusion, scene recognition engine, dynamic hardware configuration combined with feedforward and feedback, loadable algorithm library and closed-loop optimization control law, realize the real-time scene reconstruction of hardware parameters and digital algorithm;Combined with domestic single-chip selection, rigid-flex PCB and automatic calibration, meet the demand of low-cost mass production.The present application realizes the native adaptation and performance optimization of single hardware platform to voltage, current, charge, impedance and other types of sensor signals, and can be widely applied in robot dexterous hand, medical monitoring, intelligent bandage, consumer motion monitoring and industrial monitoring fields.

The invention discloses a multi-path instrumentation amplifier which comprises a low-frequency amplification circuit and a high-frequency amplification circuit which are coupled between a voltage input end and a voltage output end. The high-frequency amplification circuit comprises a first amplifier, a second amplifier, a first input resistor, a first input capacitor, a second input resistor, a second input capacitor, a first feedback capacitor and a second feedback capacitor. The reverse output end and the non-reverse output end of the first amplifier are respectively coupled with the non-reverse input end and the reverse input end of the second amplifier, and the non-reverse output end and the reverse output end of the second amplifier are coupled with the voltage output end. The first feedback capacitor is coupled between the voltage output terminal and the inverting input terminal of the first amplifier. The second feedback capacitor is coupled between the voltage output terminal and the non-inverting input terminal of the first amplifier.

A fully integrated micro search coil magnetometer (μSCM) with a low-noise instrumentation amplifier is provided for low-frequency magnetic field measurements in the range of 1Hz to 1kHz. A micro search coil formed by stacking planar spiral inductors and serially connecting them with an in-phase configuration is used for magnetic field measurements. The critical line width and inner diameter of a planar spiral inductor are theoretically calculated and experimentally verified, enabling the development of a unique CMOS layout. This layout incorporates the calculated critical inner diameter, significantly optimizing the area utilization on the CMOS die. Additionally, the CMOS die includes a polysilicon-layer inductor for on-chip calibration, a Hall effect sensor for DC magnetic field measurement, and a temperature sensor for enhanced functionality. The μSCM delivers a compact, energy-efficient, and highly sensitive solution for low-frequency magnetic field measurements, surpassing the performance of most commercially available Hall effect sensors.

The present application relates to the technical field of electronic circuit, and especially relates to a readout circuit of a terahertz detection array, which comprises: a readout link at least comprising a current feedback instrumentation amplifier, a programmable gain amplifier and an incremental analog-to-digital converter connected in sequence; the current feedback instrumentation amplifier amplifies the signal output by the detector and outputs a first-stage amplified signal, the current feedback instrumentation amplifier comprises an instrumentation amplifier body and a first ripple suppression module, the first ripple suppression module comprises a first redundant segmented current steering DAC and a first DAC code register; the programmable gain amplifier further amplifies the first-stage amplified signal, the programmable gain amplifier comprises a gain amplifier body and a second ripple suppression module, and the second ripple suppression module comprises a second redundant segmented current steering DAC and a second DAC code register. The present application effectively reduces the chip area and power consumption while ensuring that the readout circuit of the terahertz detection array has high gain, low noise and low offset.

A kind of parallel machine current adding system belongs to the technical field of electronic equipment for measurement and testing, solve how to design a kind of hardware circuit simple, control precision high parallel machine current adding and system problem;The parallel machine current adding and system of the present application, comprising: multiple single machine current sampling circuits, parallel machine current adding and circuit;Single machine current sampling circuit includes: first differential amplifier circuit, first proportional regulating circuit, first unit inverter circuit, first digital potentiometer;Parallel machine current adding and circuit includes: instrument amplifier circuit, second proportional regulating circuit, second unit inverter circuit, second digital potentiometer and multiple proportional input end resistance;Digital potentiometer is applied to parallel machine circuit, and the resistance value of potentiometer is assigned by the number of parallel machine table set to realize the adjustment of amplification factor, replace the single proportional resistance resistance value of traditional resistance proportional circuit to realize the adjustment of amplification factor, hardware circuit is simple, amplification factor control is accurate.

The invention discloses a portable human heart imaging hardware system based on bioelectrical impedance. The system comprises an excitation signal processing module, a detection signal conditioning module and a digital processing module. The excitation signal processing module adopts a DAC (Digital-to-Analog Converter) to generate an excitation signal, and after voltage amplification and band-pass filtering, the excitation signal drives an excitation electrode through an analog switch; the detection signal conditioning module switches a measuring electrode through an analog switch, a programmable instrumentation amplifier is combined with an RDAC digital potentiometer to realize self-adaptive gain adjustment of a detection signal, flexible gain of the signal is realized, and the signal is sent to an ADC after being filtered; the digital processing module carries out digital demodulation on the collected signals, extracts amplitude and phase information and then transmits the amplitude and phase information to an upper computer for image reconstruction. The flexible signal gain mechanism of the system realizes a full-custom signal gain curve, breaks through the fixed magnification gain limitation of the traditional integrated PGA, adapts to the impedance change of different individuals and experimental media, and improves the signal-to-noise ratio of the system, thereby obtaining more accurate cardiac impedance acquisition data.

This invention relates to instrumentation amplifiers and biosignal acquisition methods, specifically to a capacitively coupled instrumentation amplifier and biosignal acquisition method. It solves the technical problems of poor accuracy and integrity of biosignals acquired by existing instrumentation amplifiers, as well as their large area. This invention employs an input impedance enhancement circuit to increase the input impedance, resulting in more complete biosignals. It also uses a transimpedance matching enhancement circuit to increase the matching degree between the output signal of the feedback loop and the differential output signal. Simultaneously, by reducing the feedback capacitor to increase the closed-loop gain and lower the requirement for the input capacitor, it not only reduces the area but also increases the input impedance, improving the accuracy and integrity of the acquired biosignals. The second-order DC electrode offset cancellation circuit uses a second-order low-pass filter to narrow the transition band, more effectively separating the DC electrode offset signal from the biosignal, eliminating the DC electrode offset problem during biosignal acquisition, and making the acquired biosignals more accurate.

The invention provides a current source control method for a quantum sensor and a related device. The current source control method comprises the steps that a DAC module receives a control signal of an MCU and outputs a set voltage VSET; after the voltage VSET is set to be subjected to low-pass filtering, voltage VSET + is generated and acts on the in-phase end of the operational amplifier; filtering the output voltage Vout of the operational amplifier and outputting voltage V; an instrument amplifier is used for collecting voltage flowing through the two ends of the sampling resistor RSENSE and amplifying the voltage; voltage flowing through the two ends of the sampling resistor RSENSE is subjected to low-pass filtering to generate voltage VSET-, and the voltage VSET-acts on the anti-phase end of the operational amplifier; under the action of the negative feedback network, the output voltage VOUT of the operational amplifier is automatically adjusted until VSET + and VSET-are equal; and filtering the final output current to realize the generation of the output current IXOUT. According to the technical scheme, the technical problems that in the prior art, a current source is large in temperature drift, low in precision, poor in long-term stability, prone to being affected by aging and noise, low in bandwidth, lack of digital programmable capacity and inconvenient to adjust are solved.

The invention belongs to the field of integrated circuits, and discloses a low-voltage high-precision instrumentation amplifier analog IC (integrated circuit) chip which takes a high-performance reference current source circuit without an operational amplifier as a biasing circuit. In the low-voltage design, in order to solve the problem that the signal-to-noise ratio of the instrument amplifier is gradually deteriorated, a rail-to-rail input and output structure is adopted. According to the invention, the folded cascode structure provides a large gain and also serves as a resistor to be connected with the Miller compensation capacitor to form an unconventional RC network, so that the zero point problem is ingeniously solved, the additional chip area is not increased, and the response speed of the instrument amplifier is also improved; the MOS capacitor is used as the compensation capacitor, compared with a traditional metal capacitor, the MOS capacitor has the advantages of being high in integration level, small in area and the like, and the chip area is greatly reduced while the compensation effect is achieved.

This invention belongs to the field of industrial automation testing and metallurgical instrumentation technology, and relates to a rotary temperature measuring device for strip steel. It includes a mounting body and a rotary temperature measuring assembly located at the bottom of the mounting body. The rotary temperature measuring assembly includes a rotating roller, multiple heat-conducting elements, multiple elastic connectors, a temperature acquisition component, and a conductive slip ring. The rotating roller is rotatably mounted at the bottom of the mounting body, and multiple mounting grooves are evenly distributed along its circumference. Each elastic connector is located between a heat-conducting element and a corresponding mounting groove. The temperature acquisition component includes multiple thermocouples, a maximum voltage selection circuit, an instrumentation amplifier, and a voltage-to-frequency converter connected in series. The input terminals of the multiple thermocouples are connected to their respective heat-conducting elements, and their output terminals are electrically connected to the maximum voltage selection circuit. This invention not only accurately measures the temperature of the strip steel but also prevents signal interference.

The utility model discloses a kind of multi-loop processing CV mode electronic load instrument, it includes main control module, main power module, auxiliary power module, display module, button module, power amplifier module, communication board module and interface module.Main control module is core control unit, contains instrument amplifier, and difference proportional circuit, integrated operational amplifier circuit, advance adjustment circuit, lag adjustment circuit and analog switch, different input signal characteristics are adapted by flexible switching adjustment mode.The main power module and auxiliary power module provide stable power supply respectively;Display module and button module form man-machine interface;Power amplifier module drives high-power MOS tube to maintain constant voltage output;Communication board module supports multiple communication protocols;Interface module provides physical connection port for external equipment.The utility model significantly improves system stability and adaptability through multi-loop design, suitable for a variety of application scenarios.

A three-class AC power supply voltage value and phase sequence detection system comprises an MCU, and an AC220V / 50Hz conditioning circuit, an AC115V / 400Hz conditioning circuit, an AC380V / 50Hz conditioning circuit and a protection alarm which are electrically connected with the MCU, the AC220V / 50Hz conditioning circuit comprises a Hall voltage sensor, the input end of the Hall voltage sensor is connected with a conditioning resistor R in series and then is connected with a power supply, the output end of the Hall voltage sensor is connected with a capacitor C55 in series and then is connected with an input port of the MCU, and the protection alarm is electrically connected with the MCU. The output end of the MCU is further connected in series with a divider resistor R55 and then grounded, and the input port of the MCU is connected in series with a resistor R75 and then connected with + 3.3 V and is connected in series with a resistor R74 and then grounded; the AC115V / 400Hz conditioning circuit comprises an instrument amplifier and a voltage feedback amplifier, the input end of the instrument amplifier is connected with a power supply after being connected with a resistance voltage division circuit in series, and the output end of the instrument amplifier is connected with a positive input end of the voltage feedback amplifier after being sequentially connected with a capacitor C13 and a voltage lifting circuit in series; the output end of the voltage feedback amplifier is connected with the input port of the MCU and the negative input end of the voltage feedback amplifier. According to the scheme, voltage values of AC220V / 50Hz, AC115V / 400Hz and AC380V / 50Hz can be acquired in real time, the phase sequences of AC115V / 400Hz and AC380V / 50Hz can be measured, and timely protection and alarm can be realized.

The invention introduces a multichannel neural recording system suitable for a biosensor. The multichannel neural recording system integrates nine key modules: a band-gap reference voltage module (1), a pulse signal generator module (2), a clock signal generator module (3), an instrument amplifier module (4), an impedance boosting auxiliary loop module (5), a direct current servo loop module (6), a ripple suppression loop module (7), an ADC module (8) and a DSP module (9). The band-gap reference voltage module (1), the pulse signal generator module (2) and the clock signal generator module (3) provide stable reference voltage for the system, and pulse signals and a clock are synchronous. The impedance lifting auxiliary loop module (5), the direct current servo loop module (6) and the ripple suppression loop module (7) work cooperatively, electrode offset is effectively eliminated, and the signal quality of the instrument amplifier module (4) is improved. The system is characterized in that the multi-channel instrument amplifier module is constructed, the DSP module (9) is used for carrying out complex processing on received digital signals of the ADC module (8), and the digital signals are fed back to the instrument amplifier module, so that the signal quality is further improved. The design of the system aims at realizing efficient and accurate neural signal acquisition and processing.

The invention relates to the technical field of electromagnetic positioning, in particular to a five-degree-of-freedom sensor for electromagnetic positioning and an induction signal processing system, and the induction signal processing system adopts a three-stage circuit architecture: the first stage is an instrument amplifier pre-amplification circuit with input filtering and common-mode suppression functions; the low-noise amplifier is used for performing low-noise amplification on a microvolt-level original signal; the second stage is a Sallen-Key type active high-pass filter circuit and is used for suppressing power frequency and low frequency interference; and the third stage is a Sallen-Key type active low-pass filter circuit which is used for filtering high-frequency noise. Wherein the output of the pre-amplification circuit is connected to the third-stage low-pass filter circuit and then is cascaded with the second-stage high-pass filter circuit to jointly form a band-pass filter path, and finally, a stable analog signal with a high signal-to-noise ratio is output. The problems that a micro sensor is weak in signal, prone to interference and high in system complexity are effectively solved, and the performance and reliability of the electromagnetic positioning system in high-precision application scenes such as medical navigation and virtual reality are remarkably improved.

The utility model provides a noise suppression amplifier which comprises a first instrument amplifier, a second instrument amplifier, a first filter and a second filter, the first instrument amplifier is electrically connected with the second instrument amplifier, and the second instrument amplifier is electrically connected with the first filter; and the second filter is arranged in the first instrument amplifier or the second instrument amplifier. On one hand, the second filter can perform primary filtering on the signal input into the second instrument amplifier, so that noise in the output signal of the second instrument amplifier is effectively reduced. And on the other hand, the signal input by the second instrument amplifier is filtered into the stable low-noise signal by the first-stage filter, so that the bandwidth of the first filter can be relatively large to ensure that the driving capability of the second instrument amplifier meets the design requirement.

The invention discloses a strong PUF (Physical Unclonable Function) circuit for security protection of the Internet of Things, which comprises two TMR sensor arrays, two instrumentation amplifiers, two switched capacitor integrators and a comparator, and is characterized in that each TMR sensor array comprises a plurality of TMR sensor units, and the conduction number of the TMR sensor units in the two TMR sensor arrays is controlled through an excitation signal; two differential voltage signals are generated, two instrument amplifiers respectively carry out differential amplification on the two differential voltage signals to generate amplified voltage signals, two switched capacitor integrators respectively carry out sampling and accumulation on the amplified voltage signals to obtain sampled voltage signals, and the sampled voltage signals are output to a comparator. The comparator carries out voltage polarity judgment on the two sampling voltage signals to obtain a PUF response; the method has the advantages of high uniqueness and randomness, high stability, low bit error rate and high excitation-response pair number, and can meet the requirements of a high-reliability large-scale security authentication system.

The invention relates to the technical field of intelligent pots, and particularly discloses a temperature control system and method for an intelligent pot, and the system comprises a temperature collection module which comprises a temperature sensor and a signal conditioning circuit, and the signal conditioning circuit comprises an instrument amplifier and a low-pass filter which are electrically connected in sequence, the output end of the temperature sensor is electrically connected with the input end of the instrument amplifier; the signal input end of the core control unit is electrically connected with the output end of the low-pass filter; the power adjusting module comprises a PWM generating circuit and a power driving circuit, the control end of the PWM generating circuit is electrically connected with the PWM output end of the core control unit, and the input end of the power driving circuit is electrically connected with the output end of the PWM generating circuit; the self-adaptive power management unit comprises a DC-DC conversion circuit, and the DC-DC conversion circuit is electrically connected with the temperature acquisition module, the core control unit and the power regulation module; the problems that a temperature control system of an intelligent pot is unstable in structure, inaccurate in temperature measurement and weak in anti-interference capacity are solved.

The embodiment of the invention discloses a capacitive coupling chopping instrument amplifier circuit and a ripple calibration method. The circuit comprises a first chopping switch, an input capacitor, a first resistor, a second resistor, a two-stage operational amplifier circuit, a feedback capacitor, a second chopping switch and a ripple calibration module, the two-stage operational amplifier circuit comprises a plurality of first transistors and a plurality of second transistors which are used for signal amplification; the control end of the first transistor is connected with the first input end of the two-stage operational amplifier circuit, and the control end of the second transistor is connected with the second input end of the two-stage operational amplifier circuit; the ripple calibration module is connected with the first output end and the second output end of the two-stage operational amplifier circuit, samples signals of the first output end and the second output end of the two-stage operational amplifier circuit, and controls the access number of the first transistor and the second transistor according to the sampled signals; ripple waves generated by the chopping instrument amplifier circuit are reduced. The problem that a capacitor coupling chopping instrument amplifier circuit generates ripples due to offset voltage is solved.

The invention belongs to the technical field of sensors, and particularly relates to a high-voltage insulation isolation type voltage sensor based on a wireless energy transmission technology, which comprises a wireless energy transmission isolation power supply module, a multi-stage voltage stabilizing unit, a high-voltage dividing unit, a signal conditioning circuit and an ADC and optical fiber digital transmission circuit, the wireless energy transmission module realizes insulation power supply within an isolation distance of 5mm-500mm through electromagnetic resonance, and outputs direct current voltage; the multi-stage voltage stabilizing unit generates multiple paths of power supplies of 5V, 3.3 V and-15V; the high voltage dividing unit reduces 0-15kV high voltage into 0-10V signals according to 500: 1; the signal conditioning circuit outputs a high-precision analog signal through scaling of an instrument amplifier and second-order low-pass filtering; and the ADC and optical fiber transmission circuit digitizes the signal and converts the signal into an optical signal for transmission. According to the invention, the problems of large size, high cost and weak anti-electromagnetic interference capability of a traditional high-voltage insulation isolation type voltage sensor can be solved.

The embodiment of the invention provides a programmable gain instrumentation amplifier used in the field of sensing detection. The programmable gain network is applied to the technical field of integrated circuits and comprises a low-pass filtering module, a chopping amplification module, a first programmable gain network, a second programmable gain network and a buffer amplification module, the low-pass filtering module is used for receiving an input differential signal, filtering the differential signal and outputting a filtered signal; the chopping amplification module is used for carrying out chopping processing on the filtering signal and outputting a chopping signal; the first programmable gain network is used for performing first gain adjustment on the chopping signal and outputting a first gain adjustment signal; the second programmable gain network is used for performing second gain adjustment on the first gain adjustment signal and outputting a second gain adjustment signal; and the buffer amplification module is used for processing the second gain adjustment signal to obtain an output signal. The amplifier has the characteristics of low noise and high common-mode rejection ratio, and is suitable for detecting, amplifying and processing high-precision signals.

The application discloses an output voltage detection method and system based on an aviation power supply, and relates to the technical field of aviation power supply voltage detection; a differential voltage sensor is connected to the output end of the aviation power supply, a high-frequency suppression capacitor is connected in parallel, a sampling rate of 20-50 times the working frequency is set according to the type of the power supply, analog voltage signals are collected and converted, two-stage filtering is performed on the analog signals, the analog signals are amplified to 0-5V by an instrument amplifier, and then the analog signals are converted into digital voltage sequences by a 16-bit ADC; the effective value, peak value and other parameters of the alternating-current power supply, the average value, ripple coefficient and other parameters of the direct-current power supply are calculated; the characteristic parameters are compared with preset threshold values, and if the characteristic parameters exceed the threshold values, it is determined that an abnormality occurs and relevant information is recorded; the detection results are transmitted to a monitoring terminal through RS485, data is stored locally, and when an abnormality occurs, an output switch quantity is output to an alarm device. The application is adapted to aviation power supply load fluctuation and environmental temperature change, has high detection precision, safe data transmission and storage, can accurately identify an abnormality and give an early warning, and improves the reliability and efficiency of aviation power supply operation and maintenance.

This invention provides an electrocardiogram (ECG) instrument amplifier circuit and an ECG signal acquisition system. In the ECG instrument amplifier circuit provided by this invention, a first terminal of a first capacitor scaling circuit is connected to the first output terminal of the instrument amplifier; a second terminal of the first capacitor scaling circuit is connected to the first terminal of a first neutralizing capacitor array; the second terminal of the first neutralizing capacitor array is connected to the first terminal of a first switch; and the second terminal of the first switch is connected to the first input terminal of the instrument amplifier. A second capacitor scaling circuit has its first terminal connected to the second output terminal of the instrument amplifier; its second terminal is connected to the first terminal of a second neutralizing capacitor array; the second terminal of the second neutralizing capacitor array is connected to the first terminal of a second switch; and the second terminal of the second switch is connected to the second input terminal of the instrument amplifier. A parasitic capacitance calibration circuit is connected to both the first and second input terminals of the instrument amplifier. This ECG instrument amplifier circuit can significantly improve the input impedance of the instrument amplifier.