623 results about "Preamplifier" patented technology

The invention discloses a high-precision laser ranging system and method based on multi-frequency modulation, and relates to the field of laser ranging, and the system comprises a multi-frequency laser transmitting module which comprises generators of different frequency bands and can be independently regulated, rapidly switched and matched with a high-precision frequency modulation unit; the laser receiving and signal conditioning module is used for processing signals by using an avalanche photodiode, a low-noise preamplifier and the like; the signal processing and analyzing module is used for calculating the distance by means of a high-speed digital signal processor in combination with a multi-frequency distance measurement algorithm; a display and control module and a temperature compensation module are further included, the method comprises the steps of multi-frequency laser emission, receiving conditioning, signal processing, display control and temperature compensation, and high-precision distance measurement is achieved through fine operation according to environment and target characteristics. The method is high in distance measurement precision, and error compensation in a complex environment exceeds 90%; the adaptability is high, and automatic adjustment is achieved in different distances and environments; the real-time performance is good, and a result can be obtained within 10 milliseconds; operation is convenient, wireless and data management is supported, and laser ranging innovation is promoted.

The embodiment of the invention provides an eddy current displacement sensor and a temperature drift compensation method. The eddy current displacement sensor comprises a probe, a cable and a front-end device, the probe comprises a metal probe protection cover, and a measuring coil, a metal partition plate, a compensating coil, a metal pressing sheet and a framework body which are arranged in the metal probe protection cover, and the measuring coil, the metal partition plate, the compensating coil and the metal pressing sheet are sequentially arranged on the framework body; the first end of the compensating coil and the first end of the measuring coil are both connected with the front-end device, and the front-end device is used for carrying out differential processing on a measuring signal sensed by the measuring coil and a compensating signal sensed by the compensating coil to obtain distance information. The sensor provided by the embodiment of the invention can provide high-precision displacement measurement in a complex environment, is suitable for various industrial application scenes, especially in an environment with high temperature or large temperature fluctuation, and ensures the reliability and accuracy of a measurement result.

The utility model discloses a turbine flow meter, which belongs to the technical field of turbine flow meters and comprises a flow meter body, a flange plate is mounted at the end of the flow meter body, a preamplifier is fixedly connected to the upper end of the flow meter body, a magnetoelectric converter is mounted in the preamplifier, and the magnetoelectric converter is fixedly connected with the flange plate. A front guide piece and a rear guide piece are fixedly connected to the interior of the flow meter body, an impeller is connected between the front guide piece and the rear guide piece through a bearing, a filtering disc is installed in the flow meter body, and the upper end and the lower end of the filtering disc are connected with the interior of the flow meter body through auxiliary springs; a center rod is installed in the middle of the filtering disc, and a positioning rod is inserted into the center rod. According to the turbine flowmeter, after the filter screen is blocked, automatic cleaning of the filter screen can be achieved through fluid thrust, and meanwhile when the turbine flowmeter is connected with an external pipeline, the stability of connection between the pipeline and the turbine flowmeter is effectively guaranteed.

The invention relates to the technical field of intelligent diagnosis systems for neurodegenerative diseases, and discloses a system and equipment for identifying an early biomarker of Parkinson's disease based on non-invasive electroencephalogram. The Parkinson's disease early-stage biomarker identification system comprises a multi-mode signal acquisition module which is provided with a 64-lead dry electrode electroencephalogram cap, an integrated preamplifier and an ADC converter and is used for synchronously acquiring resting-state electroencephalogram and event-related potential, dynamically completing switching of the resting-state electroencephalogram sampling rate and transmitting acquired original data to a preprocessing module. According to the method, revolutionary improvement is realized in three dimensions of acquisition, analysis and calculation through system-level collaborative innovation, a nanocrystalline shielding dry electrode is combined with a dynamic impedance adjustment technology, so that the signal-to-noise ratio of a home environment is increased to 28dB, and the pathological correlation of key markers such as frontal lobe-basal node loop gamma entropy is verified by Granger causality and has a good application prospect. The cloud distributed model server supports 2000 paths of concurrent analysis, and the real-time bottleneck of home screening is thoroughly solved.

The axial vibration reduction device comprises a displacement sensor and an axial vibration reduction assembly which are arranged on a rotating shaft of the speed reducer, and further comprises a pre-amplifier, an acquisition and analysis module, a control module and a power supply module. The axial vibration reduction assembly comprises a magneto-rheological elastomer, a magnetism isolating ring, a magnet exciting coil and a metal shell which are sequentially arranged around the rotating shaft from inside to outside. The control module adjusts the rigidity of the magneto-rheological elastomer by changing an electric signal of the magnet exciting coil so as to achieve stepless adjustment of the axial damping force of the rotating shaft, axial vibration loads are attenuated through the magneto-rheological elastomer and then transmitted to the pure iron shell and the base, and the axial vibration reduction effect is improved. The multiple angular contact ball bearings are arranged to block direct impact of vibration loads in two directions one by one, disturbance caused by different vibration loads due to different vibration directions is avoided, more vibration loads are eliminated by the magnetorheological elastomer, and the axial vibration reduction efficiency is further improved.

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 relates to the field of crystal detection, and discloses a multifunctional comprehensive scintillation crystal and semiconductor material energy spectrum test system, which comprises a crystal adaptation module for judging the type and size of a placed crystal through an optical identification and parameter matching mechanism, and a signal acquisition module for amplifying, filtering and digitally processing an acquired signal, the signal correction module is used for correcting waveform distortion and baseline drift through a dynamic gain adjustment algorithm of a low-noise pre-amplifier and a multi-channel pulse analyzer; the data analysis module is used for generating an energy spectrum curve according to input signals and calculating energy resolution, counting rate, light attenuation time or carrier mobility, and the environment calibration module is used for dynamically evaluating shading degree, environment light, temperature and electromagnetic interference through an optical sensor and a temperature and humidity detector in the camera obscura and outputting updated calibration parameters. The method has the advantages of improving the detection efficiency, precision and consistency.

The invention relates to the technical field of optical fiber transmission, and discloses a bidirectional optical fiber transmission system. Comprising a first wavelength division multiplexing / demultiplexing device, a second wavelength division multiplexing / demultiplexing device, a first power amplifier, a second power amplifier, a first preamplifier, a second preamplifier, a first optical fiber switching module, a second optical fiber switching module, a first filter, a second filter, a third filter and a fourth filter. The first optical fiber switching module and the second optical fiber switching module are provided with a first optical fiber or a second optical fiber for transmitting optical signals; according to the technical scheme, automatic switching to the standby optical fiber link is supported when the single optical fiber link fails or the performance is reduced, shunting and combining of wave band signals are achieved through the filter, and the stability and the anti-interference capability of transmission signals are ensured.

The invention discloses a low-noise and high-precision analog front-end circuit for biological signal acquisition. The low-noise and high-precision analog front-end circuit comprises a chopping capacitance coupling type instrument amplifier circuit, a switched capacitor type programmable gain amplifier circuit and a Sigma-Delta analog-to-digital converter modulator circuit. T-type capacitance feedback, chopping modulation and programmable technologies are introduced on the basis of an existing amplifier, and the low-noise and programmable gain functions of the pre-amplifier are achieved. Through the three-order one-bit quantized feed-forward chopping type Sigma-Delta modulator, the signal to noise ratio and the effective bit number of the signal are improved. Compared with the prior art, the analog front-end circuit not only has the capability of changing the gain multiple according to the bio-electricity signal, but also has the low-noise and high-precision signal processing effect, and the problems that a traditional analog front-end circuit is large in noise and low in signal processing precision are solved. In addition, the biological signal acquisition-oriented circuit provided by the invention can also be used in other analog front ends, such as an audio processor and the like, and is wide in application range.

The invention relates to the technical field of photoacoustic spectrometry, in particular to a gas detection device and method based on a 3D printing Helmholtz photoacoustic cell, and is suitable for the fields with load requirements such as unmanned aerial vehicle-mounted gas monitoring platforms. In order to overcome the problems of large volume, heavy weight, complex structure and low integration level of a photoacoustic gas sensor in the prior art, the lightweight Helmholtz photoacoustic cell structure manufactured based on 3D printing comprises a sound wave generation cavity, a small-diameter connecting pipe and a detection cavity which are integrally formed, an optical reflection unit is integrated in the sound wave generation cavity, and the optical reflection unit is integrated in the detection cavity. Two concave reflectors are arranged to reflect incident light beams for 160 times, a laser, an optical fiber collimator, a pre-amplifier, a lock-in amplification circuit board, a notebook computer and a current temperature control module are arranged outside, and the concentration of gas to be detected is obtained through analysis and processing of the notebook computer.

A radio frequency (RF) power generator adapted for coupling to a multi-station integrated circuit fabrication chamber may include an oscillator to provide a periodic signal and one or more preamplifiers each having an input port to receive a signal from the oscillator and having an output port to provide an amplified signal. The RF generator may additionally include one or more constant-gain amplifiers, each having an input port to receive a signal from the one or more preamplifiers, and an output port configured for coupling an amplified signal to an electrode for generating a plasma in an assigned station of the multi-station integrated circuit fabrication chamber.

The invention relates to the technical field of detection and calibration, in particular to an instrument metering detection and calibration method and system. The method comprises the following steps: analyzing a running state log of a current meter, extracting multi-frequency instantaneous overload current waveform time domain data, and carrying out shunting resistor resistance drift simulation analysis based on the data to obtain resistance drift data; then, quantizing the drift data to obtain a resistance drift intensity segmentation index, and based on the resistance drift intensity segmentation index, carrying out pre-amplifier gain error nonlinear quantization to obtain gain error data; thirdly, error increment change data is obtained through error change multi-point calibration, multi-point segmentation error calibration is carried out based on the error increment change data, and finally multi-point segmentation error calibration learning data is obtained. According to the method, the detection and calibration technology is optimized, so that the detection and calibration technology is more accurate.

A latch comparator is disclosed. The latch comparator includes a first reservoir capacitor; a preamplifier including first and second transistors respectively connected to first and second inputs, the first and second transistors selectably connectable to a first terminal of the first reservoir capacitor, and third and fourth transistors respectively connected to the first and second inputs, the third and fourth transistors selectably connectable to a second terminal of the first reservoir capacitor; and a latch, including a first portion serially connected between the first and third transistors and connected to a first output, and a second portion serially connected between the second and fourth transistors and connected to a second output.

The invention belongs to the technical field of analog integrated circuits, and particularly relates to a comparator circuit for a successive approximation type ADC (Analog to Digital Converter), which comprises a pre-amplifier stage circuit and a latch stage circuit, the pre-amplifier stage circuit is a cross coupling operational amplifier, and the latch stage circuit is a stroke-arm type latch comparator; a clock signal CLK is respectively input to the power supply ends of the cross coupling operational amplifier and the latch comparator; the positive input end of the cross-coupled operational amplifier is connected with a VIP signal, the negative input end of the cross-coupled operational amplifier is connected with a VIN signal, the negative output end of the cross-coupled operational amplifier is connected with the negative input end of the latch comparator, and the positive output end of the cross-coupled operational amplifier is connected with the positive input end of the latch comparator; a two-stage structure is adopted in the circuit structure, the characteristic that the first-stage operational amplifier is easy to process low voltage is combined with the characteristic that the second-stage latch is easy to process high voltage, and the voltage comparison speed of the comparator is effectively increased.

The invention relates to the technical field of magnetic resonance imaging, in particular to a coil assembly and equipment for magnetic resonance imaging of double knee joints and single knee joint. The coil assembly comprises: N left knee coil units for receiving magnetic resonance signals from a left knee; n right knee coil units for receiving magnetic resonance signals from right knees; the N first preamplifiers are connected with the N left knee coil units in a one-to-one correspondence manner; the N second pre-amplifiers are connected with the N right knee coil units in a one-to-one correspondence manner; the switching device is used for being connected to a power supply node, coupling the power supply node to the N first preamplifiers and decoupling the power supply node from the N second preamplifiers in a first working state; in the second working state, the power supply node is coupled to the N second pre-amplifiers, and the power supply node is decoupled from the N first pre-amplifiers; in a third operating state, the power supply node is coupled to the N first preamplifiers and the N second preamplifiers.

The invention relates to a fully differential input dynamic latch comparator applied to a flash ADC (Analog to Digital Converter). The fully differential input dynamic latch comparator comprises a non-overlapping clock, a preamplifier, a dynamic latch comparator, an RS trigger and a switched capacitor module. The two-phase non-overlapping clock module is used for generating clocks clk1 and clk2 and respective early turn-off clocks clk1a and clk2a. And the pre-amplifier module is used for summing and amplifying the input differential signal and the reference voltage of the comparator. And the dynamic latch comparator module is used for comparing the output of the pre-amplifier to obtain a final result. The RS trigger is used for latching a comparison result for a half period, and the input end of the amplifier and the input end of the comparator are connected to the capacitor formed by the MOS tube to reduce kickback noise.

A current sense amplifier measures a voltage drop in a drive transistor LS to measure the current flowing through the drive transistor LS. The current sense amplifier includes a preamplifier pre-amp, to which a voltage across the drive transistor LS is inputted, and which obtains a positive output and a negative output corresponding to a voltage difference of the inputted voltage across the drive transistor; and a switch sw, which connects the input end of a common mode voltage vcm and the negative output, the common mode voltage vcm serving as the operation reference of the preamplifier pre-amp. A change of the positive output caused by turning on / off the switch sw can be detected.

The invention provides a high-integration-level signal reading module for a neutron proportional counter tube, and belongs to the technical field of neutron detection, the high-integration-level signal reading module comprises stacked double-layer circuit boards, and the upper circuit board and the lower circuit board are connected through pin interfaces; the upper circuit board is provided with a signal processing circuit which is used for reading, amplifying, discriminating and shaping signals of the neutron proportional counter tube. The lower-layer circuit board is provided with a positive and negative dual-power-supply support circuit which provides + / -3.3 V power supply support for the signal processing circuit of the upper-layer circuit board. The module supplies power through the lower-layer power panel, and the lower-layer circuit board supplies positive and negative power to the upper-layer circuit board after completing power conversion. Signals are input through the IPX interface of the upper-layer circuit board and are output through the other IPX interface after being processed. The charge sensitive pre-amplifier, the broadband voltage amplifier, the pulse discriminator circuit, the pulse shaping circuit and the power management module are integrated in the same module, so that the real integrated design is realized.

The invention relates to the technical field of nuclear magnetic resonance, and discloses a nuclear magnetic resonance preamplifier circuit which comprises a gating module and a first-stage amplification submodule. The gating signal end of the gating module is connected to the control end of the third switching tube and the control end of the fourth switching tube through a first resistor; a second power supply end is connected to a second node through a sixth resistor and a second inductor; the second node is grounded through the first switching tube; a second power supply end is connected to a second node through a sixth resistor and a second inductor; and the second node is also grounded through a fifth capacitor. A gating control signal is added on the basis of the low-noise amplifier, and bias voltage of the first switching tube is closed or opened in a radio-frequency transmitting mode and a radio-frequency receiving mode respectively, so that closing and working conversion time, namely recovery time, is prolonged.

The invention belongs to the technical field of electrical equipment insulation detection, and particularly relates to a cable insulation wide-temperature-range dielectric loss detection system which comprises a human-computer interaction interface, a main control processor, an acquisition card, a linear high-voltage amplifier, a micro-current preamplifier, a three-electrode test, a gear shifting communication control module, a power module and a signal conditioning module. The main control processor is connected with the power supply module and the acquisition card, the main control processor is connected with the temperature sensor through the signal conditioning module, the acquisition card is connected with the linear high-voltage amplifier and the micro-current pre-amplifier, and the micro-current pre-amplifier is connected with the gear shifting communication control module; the ultrathin thin film resistance type PT100 temperature sensor is combined with a wave-shaped groove isolation structure, so that the heat conduction error of adjacent temperature measurement nodes is effectively reduced. The depth of the wave-shaped groove is 1.5-3 times of the wire diameter of the thermocouple, and the groove is filled with a nanometer aerogel heat insulation material, thereby guaranteeing the independent measurement of a temperature field, and enabling the thermal interference among a plurality of measurement points to be reduced.

The utility model belongs to the technical field of hydrophones, and particularly discloses a hydrophone filled with silicone oil, which comprises a first shell, a second shell, a printed circuit board assembly and a cable, the first shell is made of an underwater sound transmission material, one end of the first shell is connected with the second shell, a closed cavity is formed between the interior of the first shell and the second shell, and the closed cavity is filled with silicone oil; the printed circuit board assembly is integrated with a pre-amplifier chip and an MEMS chip used for sensing sound signals, and the printed circuit board assembly is arranged in the closed cavity and soaked in the silicone oil. The cable passes through the second housing, and the wiring end of the cable is connected with the board body of the printed circuit board assembly. According to the hydrophone filled with the silicone oil, the product structure is simplified, the number of parts is greatly reduced, and production and processing are facilitated; silicone oil is poured into the closed cavity, so that the printed circuit board assembly is completely soaked in the silicone oil, and meanwhile, a pre-amplifier is arranged in the hydrophone, so that the sensitivity and hydrostatic pressure resistance of the hydrophone are improved.

The invention discloses a front-end reading circuit suitable for a high-purity germanium detector. The front-end reading circuit comprises a pre-amplifier, a filtering shaping circuit, an amplitude acquisition channel, a time discrimination channel and an automatic gain control circuit, the output end of the pre-amplifier is connected with the filtering and shaping circuit, the output end of the filtering and shaping circuit is connected with the amplitude acquisition channel and the time discrimination channel, and the output of the amplitude acquisition channel is input into an ADC module of the digital amplitude analyzer; the time discrimination channel is used for extracting time information of particles reaching the detector, and an obtained pulse signal is used as a control signal of the amplitude acquisition channel and is also input to the TDC module of the digital amplitude analyzer; a control signal of the automatic gain control circuit is generated by the external processor according to the output of the digital amplitude analyzer, and an output signal of the automatic gain control circuit is used as a control signal of the preamplifier. The advantages of the detector can be fully utilized, and resource waste is avoided.

The invention provides a high-sensitivity temperature compensation Hall switch device. The high-sensitivity temperature compensation Hall switch device comprises a Hall switch module, a temperature compensation module, a signal processing module and a power management module. The Hall switch module comprises a Hall element, a pre-amplifier and a comparator and is used for detecting and amplifying an external magnetic field signal; the temperature compensation module comprises a temperature sensor, a compensation controller and a compensation element and is used for realizing accurate temperature compensation; the signal processing module comprises a filter and a logic control unit, and is used for filtering noise and generating a final switch control signal; the power management module comprises a main power supply and a standby power supply to ensure stable power supply. The device can improve the temperature compensation precision, enhance the switch sensitivity, reduce the power consumption, and meet the high-precision and high-reliability requirements of modern electronic equipment.

A flexible printed circuit (FPC) for a hard disk drive includes a first preamplifier electrically connected to first read-write transducers and a second preamplifier electrically connected to second read-write transducers, where all transducers are driven via a single primary actuator, with a top FPC section including electrical traces between a fine actuator corresponding to one of the first transducers and a corresponding controller and a bottom FPC section including traces between a fine actuator corresponding to one of the second transducers and a corresponding controller. To inhibit potential crosstalk between the fine actuator traces and read traces and / or voice coil motor (VCM) traces, the fine actuator traces may be positioned not-adjacent to read traces, such as between write traces adjacent the read traces and serial input / output (SIO) traces adjacent VCM traces, and / or at least five trace-widths away from the VCM traces.

The invention relates to a radio frequency coil assembly suitable for a magnetic resonance system, the magnetic resonance system and a control method. The radio frequency coil assembly comprises a coil body formed by arranging a plurality of coil units, and the mode switching circuit is connected with at least one coil unit and used for controlling the coil unit to be switched from a transmitting mode to a receiving mode or from the receiving mode to the transmitting mode. The mode switching circuit is arranged between the radio frequency power amplifier and the coil unit, the pre-amplifier is used for amplifying magnetic resonance signals received by the coil unit, and the matching circuit is arranged between the mode switching circuit and the pre-amplifier and is used for realizing power matching between the radio frequency power amplifier and the coil unit or realizing noise matching between the coil unit and the pre-amplifier. By adopting the arrangement of the invention, the working mode of the radio frequency coil can be conveniently and quickly switched, and the radio frequency assembly and the receiving coil are used for receiving magnetic resonance signals to obtain richer acquisition information, so that the signal-to-noise ratio of a reconstructed image is improved.

The invention relates to the technical field of low-temperature infrared radiation detection, and provides low-temperature infrared radiation detection equipment, which comprises a vacuum cold box, an infrared detection device, a control system and a signal processing system, and is characterized in that the infrared detection device comprises an infrared window sheet, an optical shutter, an optical lens, an optical chopper and an infrared detector; the optical chopper adjusts an infrared radiation signal emitted by a target object to a predetermined frequency, and the infrared detector receives the infrared radiation signal and converts the infrared radiation signal into an electric signal; the signal processing system comprises a pre-amplifier, a lock-in amplifier, a signal processing unit and a display unit, the pre-amplifier amplifies the electric signals output by the infrared detector, and the lock-in amplifier extracts signals corresponding to the preset frequency from the electric signals amplified by the pre-amplifier and amplifies the signals. Through the arrangement, the optical chopper, the pre-amplifier and the lock-in amplifier are combined, so that the measurement precision of infrared detection is effectively improved.

A system and method are disclosed for a superconducting traveling-wave parametric amplifier (TWPA) with improved control and performance. In a preferred embodiment, the amplifier comprises an integrated array of symmetric rf-SQUIDs in a transmission line structure. A device was fabricated using niobium superconducting integrated circuits, and confirmed predicted performance, with a maximum gain up to 17 dB and a bandwidth of 4 GHz. A similar device can be applied as a low-noise, low-dissipation microwave amplifier for output from a superconducting quantum computer, or as a preamplifier, switch, or frequency converter for a sensitive microwave receiver, or as an output amplifier for a frequency-multiplexed superconducting detector array.

The present invention discloses a displacement measurement device and a displacement measurement method for an eddy current sensor. The displacement measurement device includes: an eddy current sensor, a preamplifier, which is provided with a variable resistor and a resonant capacitor connected in series in sequence, and the resonant capacitor is adapted to be connected in parallel with the probe inductor; a voltage acquisition module, which is arranged in the preamplifier; a controller, which is provided with a control end and a first acquisition end, the control end is connected to the variable resistor, and the first acquisition end is connected to the voltage acquisition module; when the peak-to-peak voltage of the resonant voltage is not within a preset range, the controller adjusts the resistance value of the variable resistor to make the peak-to-peak voltage of the resonant voltage within the preset range. This ensures the consistency of the output signal of the eddy current sensor, ensures the accuracy of the position detection of the magnetic levitation system, thereby improves the stability of the magnetic levitation bearing control system, and reduces the output difference caused by the matching of the sensor probe with different preamplifiers.

The invention relates to the technical field of wireless acquisition of physiological parameters, in particular to a dynamic multi-modal wireless acquisition system for physiological parameters. The system comprises a physiological parameter acquisition module and a physiological parameter signal modulation module, the physiological parameter signal modulation module comprises a preamplifier and an electromyographic signal decomposition unit, electromyographic signals are subjected to modal decomposition, and an extreme value distribution comparison sequence and a signal difference comparison sequence are constructed; the comparison characteristic value unit is used for acquiring a comparison characteristic value of each modal component; the consistency coefficient unit is used for determining consistency coefficients of the electromyographic signals at different positions; the electromyographic signal filtering unit is used for adjusting a filtering window during electromyographic signal filtering; an electromyographic signal analog-to-digital conversion unit; a physiological parameter wireless communication module; and a power management module. According to the invention, the accuracy of wireless acquisition of dynamic multi-modal physiological parameters is improved.

The invention relates to a reset circuit of a charge sensitive preamplifier. The circuit comprises a trigger signal generation module, a control signal generation module and a reset module, the trigger signal generation module is used for generating a reset trigger signal when the output voltage of the charge sensitive pre-amplifier is increased to the upper threshold voltage or reduced to the lower threshold voltage; the control signal generation module is used for generating a reset control signal according to the reset trigger signal; the reset module is used for generating a reset charge signal in response to the reset control signal and inputting the reset charge signal to the input end of the charge sensitive preamplifier, so that the output voltage is reset to a preset voltage; the reset circuit does not change the working state of the charge sensitive pre-amplifier in the reset process, the problems of gain abrupt change and unstable working state of the amplifier in the reset process are avoided, structures such as a feedback resistor which additionally generates leakage current and noise do not need to be used in the circuit, and the noise performance cannot be deteriorated.