385 results about "Preamplifier" patented technology

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 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.

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.

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-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.

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 refers to a hybrid integrated silicon drift detector (HiSDD) for X-ray detection, particularly to a HiSDD combining a silicon drift detector (SDD) with a low-noise preamplifier on a SDD sensor chip to improve the electrical and structural properties of the detector assembly. The invention further refers to a corresponding method for the fabrication of a HiSDD. A HiSDD according to the invention hybridly integrates a silicon drift detector, SDD, sensor chip and a preamplifier module; wherein electrically conductive paths are formed on a surface of the SDD sensor chip, having first ends configured for flip chip bonding and second ends configured for wire bonding; wherein the preamplifier module having contacts disposed on a surface of the preamplifier module, and wherein the first ends of the electrically conductive paths are flip chip bonded to the contacts of the preamplifier module.

The invention provides an electroencephalogram synchronous acquisition system compatible with nuclear magnetic resonance. The problem of interference of traditional equipment in a strong magnetic field environment is solved through innovative material selection and structural design. According to the system, a platinum-iridium alloy multi-contact implantable electrode probe is adopted and is matched with a nuclear magnetism compatible electrode wire formed by a silver-plated copper wire core body and a silver-plated nylon shielding layer, so that indoor and outdoor long-distance signal transmission of MRI (Magnetic Resonance Imaging) is realized. The signal acquisition and processing unit integrates a non-magnetic ceramic packaging pre-amplifier and an optical fiber isolation transmission data acquisition card, and is matched with a fan-free design computer, so that the influence of a magnetic field on signal processing is thoroughly avoided. According to the scheme, real-time electroencephalogram monitoring in experimental animal task state functional nuclear magnetism is supported, experiments prove that the signal-to-noise ratio is reduced by 30% or above, the distortion rate is controlled to be 2% or below, the advantages of high biocompatibility, low cost and operability are achieved, and the accuracy and reliability of scientific research data collection are remarkably improved.

The invention discloses a 1319nm laser based on a torsional mode cavity and a lath configuration, which belongs to the technical field of solid lasers and comprises an oscillator stage, a pre-amplifier, a first-stage main amplifier and a second-stage main amplifier which are sequentially arranged, the oscillator stage generates a [mu] J magnitude narrow linewidth pulse laser and outputs the [mu] J magnitude narrow linewidth pulse laser to the pre-amplifier, the pre-amplifier amplifies the incident narrow linewidth pulse laser to an mJ magnitude and outputs the laser to the first-stage main amplifier, the first-stage main amplifier amplifies the incident narrow linewidth pulse laser to a dozens of mJ magnitude, and the second-stage main amplifier outputs the amplified laser to the second-stage main amplifier. The second-stage main amplifier amplifies the incident narrow-linewidth pulse laser to a magnitude of hundreds of mJ, and outputs the narrow-linewidth pulse laser to the second-stage main amplifier. The system outputs narrow-linewidth pulse laser with excellent light beam quality, and can be widely applied to the field of laser radar detection.

The utility model discloses a high-density deployment noise monitoring micro-station in the technical field of noise monitoring, which comprises a capacitive sensor, a preamplifier, an ADC (analog to digital converter) circuit, an AGC (automatic gain control) circuit, an MCU (microprogrammed control unit) system and a wireless communication module. The pre-amplifier is used for amplifying an analog signal according to a certain multiple, the ADC circuit is used for the analog-to-digital conversion circuit and converting an analog electric signal into a digital electric signal, the AGC control circuit is used for the automatic gain control circuit, and the MCU system is used for processing, operating and storing received data and controlling an AGC amplification multiple and a communication mode. The wireless communication module is used for transmitting data processed by the micro-station MCU system through a long-distance wireless communication technology or receiving external data, low power consumption and miniaturization of the noise monitoring station are achieved through combination of all aspects, the noise monitoring station can be conveniently installed on any fixable places such as a wall, a trunk and an electric pile, and high-density deployment is achieved.

The present application relates to the field of analog integrated circuit technology, and particularly relates to a kind of sampling and holding circuit based on noise cancellation.The present application handles sampling noise by introducing noise cancellation technology, input signal is directly connected to the upper plate of C1, C1 samples during S1 switch is closed;The output end of operational amplifier is connected with the lower plate of C2 through S2 switch, C2 samples sampling noise during S2 switch is closed, C2 two ends are connected with C1 two ends through S3 switch, C1 and C2 share charge during S3 switch is closed;Dynamic operational amplifier output end is connected with latch at the same time, so as to use operational amplifier as the preamplifier of comparator.The present application effectively suppresses the deterioration of sampling noise under the condition of reducing sampling capacitor, and dynamic operational amplifier greatly reduces the power consumption and noise of sampling and holding after introducing operational amplifier, and C2=C3 can also be set to make the gain of dynamic operational amplifier in noise elimination stage and subsequent as comparator preamplifier be equal, further improve the precision of circuit.

A first circuit receives a single-ended signal and a reference voltage. The first circuit shifts a common mode of the single-ended signal based on a level-shifting current. A preamplifier receives the single-ended signal and the reference voltage from the first circuit and amplifies the single-ended signal to obtain an amplified signal. A decision feedback equalizer (DFE) system receives the amplified signal and the reference voltage from the preamplifier. The DFE system generates a first average signal height of the amplified signal above the reference voltage and a second average signal height of the amplified signal below the reference voltage. A second circuit provides the level-shifting current to the first circuit and adjusts the level-shifting current based on a linearity parameter associated with the amplified signal.

The utility model discloses an acoustical preamplifier, which relates to the related technical field of amplifiers, and comprises a preamplifier and a windshield, the preamplifier is connected with a microphone, the preamplifier comprises a shell, an inner cavity penetrating up and down is arranged in the shell, a probe is arranged in the inner cavity, and the probe is connected with the windshield. The inner wall of the inner cavity is provided with a shielding cylinder capable of moving up and down, the shielding cylinder sleeves the outer side of the probe, the shielding cylinder is movably connected with the inner wall of the inner cavity, and the upper end of the shielding cylinder abuts against the microphone; according to the utility model, the shielding cylinder is movably installed in the inner cavity, the shielding cylinder is easy to store, the shielding cylinder can stretch out conveniently when the shielding cylinder needs to be used, the probe can be protected, signals can be protected from being interfered, and the spring in the inner cavity can control the shielding cylinder to pop out autonomously, so that the probe can be better protected.

A kind of analog-digital converter is disclosed.The analog-digital converter includes: comparator, is configured to: input signal is compared with reference signal, and output comparison signal indicating corresponding comparison result;Control logic is configured to output control signal for adjusting reference signal based on comparison signal;And reference signal adjusting circuit is configured to adjust reference signal based on control signal.Comparator includes: first preamplifier, is configured to: using first transistor with first size, the difference between input signal and reference signal is amplified;Second preamplifier, is configured to: using second transistor with second size different from first size, the difference between input signal and reference signal is amplified;And latch, is configured to: using at least one of the output of first preamplifier and the output of second preamplifier, comparison signal is generated.First preamplifier and second preamplifier share latch.

The utility model discloses a dual-output high-precision vehicle-mounted GNSS (Global Navigation Satellite System) antenna, and relates to the technical field of positioning antennas. The receiving unit comprises a first microstrip patch, a second microstrip patch, an L1 antenna feed network, an L2 antenna feed network, an L1 prefilter, an L2 prefilter, an L1 pre-amplifier, an L2 pre-amplifier, an L1 filter, an L2 filter, a pilot frequency combiner circuit, a final amplifier, a splitter, a power switching circuit, a first switch, a second switch, a first connector and a second connector. The first microstrip patch is arranged above the second microstrip patch, and the L1 antenna feed network and the L2 antenna feed network are connected to the second microstrip patch. The device can realize miniaturization, expand the impedance bandwidth of the antenna, realize the reception of multi-constellation satellites and low-elevation satellites of the antenna, and meet the requirements of a high-precision inertial navigation module on the antenna.

The invention relates to a photoacoustic liquid viscosity detection device and method based on spectrum resolution, and belongs to the field of photoacoustic detection and liquid physical property analysis. The device comprises a solid-state laser, a collimating lens, a plane mirror, a plate-type semitransparent mirror, a microscope objective lens, a photodiode, a photoacoustic coupling cavity, a rectangular prism group, an ultrasonic transducer, a pre-signal amplifier, a digital oscilloscope and a computer. Pulse laser is focused to a liquid sample after being processed by an optical path to excite a photoacoustic effect, an ultrasonic transducer receives a signal and converts the signal into an electric signal, after a digital oscilloscope synchronously samples, a computer extracts a frequency spectrum full width at half maximum (FWHM) through fast Fourier transform, and non-contact detection is realized based on a negative correlation between the frequency spectrum full width at half maximum and viscosity. The method can overcome the defects of large sample size, mechanical contact and the like of a traditional method, and is suitable for high-precision viscosity detection of biological tissues and industrial samples in the field of biomedicine.

The invention discloses a piezoelectric circular tube transducer which comprises a piezoelectric ceramic circular tube. The pre-amplifier is arranged in the fixed structural member; the fixing structural member is filled with an elastic material so as to elastically fix the pre-amplifier; the fixed structural member is arranged in the piezoelectric ceramic circular tube, the fixed structural member is sealed at one end of the piezoelectric ceramic circular tube, and the other end of the piezoelectric ceramic circular tube is sealed by an end cover; the first metal lead terminal is inserted into the lead terminal jack of the fixed structural member, and a signal output lead of the pre-amplifier is electrically connected with the first metal lead terminal; a second metal lead terminal is inserted into a corresponding lead terminal jack of the fixed structural member, and a power supply lead of the pre-amplifier is electrically connected with the second metal lead terminal; an input lead of the pre-amplifier is connected with a positive electrode lead of the piezoelectric ceramic circular tube; and a negative lead of the pre-amplifier is connected with a negative electrode lead of the piezoelectric ceramic circular tube. External electromagnetic noise can be effectively isolated.

Provided is an X-ray fluorescence analyzer capable of performing an analysis under more favorable conditions depending on an analysis target. The X-ray fluorescence analyzer includes a detector 30, preamplifiers 41A, 41B configured to amplify a detection signal from the detector into a staircase wave signal at different signal amplification factors GA, GB, a differentiating circuit 42 configured to convert the staircase wave signal into a differential wave signal, an A / D converter 43 configured to convert the differential wave digital signal to a digital signal, a signal processing unit 160 configured to detect a peak value from the digital signal, discriminate and count the peak value, and generate a histogram, and an input unit 51 configured to set the energy range of the fluorescent X-rays to be analyzed. Any one of the preamplifiers is automatically selected based on maximum energy in the set energy range.

The present disclosure is directed to a light-signal communication receiver device including a photo-receiving diode configured to generate a current signal on a first node from a received light signal, a preamplifier configured to convert the current signal on the first node into a voltage signal on a second node, and a differential amplifier including a first input connected to the first node and a second input connected to a third node coupled to the second node via an adjustment circuit. The adjustment circuit is configured to offset the level of the voltage signal of the second node, on the third node, in a controlled manner by a control signal.

This invention discloses an active coupling cavity device and calibration method for calibrating a standard microphone. A sound source adapter is located at the signal input end of the active coupling cavity. A multi-channel sound field distribution structure is located within the active coupling cavity, comprising eight acoustic channels evenly distributed circumferentially along the central axis of the active coupling cavity. A symmetrical clamping assembly constrains the reference microphone and the microphone under test to be symmetrical about the central axis of the active coupling cavity. A coaxiality test ring assembly rigidly constrains the axes of the reference microphone and the microphone under test to coincide with the central axis of the active coupling cavity. The calibration test system includes a signal generator, a sound level meter under test, a preamplifier, a measurement amplifier, a bandpass filter, and a digital voltmeter. The multi-channel uniformly distributed sound field structure solves the problem of uneven sound pressure distribution caused by unidirectional input, and the symmetrical clamping assembly and the coaxiality test ring assembly respectively solve the problem of poor consistency in low-frequency and high-frequency phase measurements.

The application discloses a kind of digital frequency tracking and synchronous sampling control system for resonant gyro, including self-excitation oscillation and automatic gain control device, preamplifier circuit and digital signal processor, digital signal processor includes first A / D conversion unit, second A / D conversion unit, frequency error detection unit FD, phase error detection unit PD, digital control oscillator NCO, sampling frequency generator and quadrature demodulation unit, the vibration signal of drive channel is handled after device output to first A / D conversion unit, conversion obtains the vibration signal after conversion, FD obtains frequency difference by frequency error detection, PD obtains phase difference by phase error detection, NCO is adjusted the frequency and phase of sampling frequency generator according to frequency difference and phase difference in real time, until the resonant frequency and phase of drive channel are tracked;The vibration signal of detection channel is handled after circuit output to second A / D conversion unit, obtains the vibration signal after conversion, and quadrature demodulation unit carries out quadrature demodulation and obtains speed signal.

A radio frequency (RF) receiver assembly (100) for use in a magnetic resonance imaging (MRI) system is described. The receiver assembly (100) comprises a primary resonant circuit (101) coupled to a preamplifier (106) via capacitive coupling, and a secondary resonance circuit (104) comprising of at least one inductor (104a) coupled between a first switch (103) and the capacitive coupling. The first switch (103) is circuited between the primary (101) and the secondary (104) resonant circuits, and the preamplifier (106).

The invention discloses a magneto-optical effect-based dynamic zooming method and an optical system, and the method comprises the steps: arranging at least one magneto-optical crystal between a pre-amplifier and a main amplifier, so as to achieve the dynamic zooming through the magneto-optical effect; wherein the magneto-optical crystal is obtained by combining anisotropic materials with matched refractive indexes, and the anisotropic materials are processed into complementary parabola shapes. According to the invention, the magneto-optic effect is utilized to realize dynamic zooming, and the mode of complementary combination of the crystals with matched refractive indexes is utilized to solve the problem that the additional wavefront shape does not conform to the demand. Compared with an electro-optical effect scheme, an applied magnetic field is a uniform magnetic field along a transmission direction, so that a depolarization problem caused by a transverse component is avoided; compared with the scheme of aperture division, grating division and the like, the dynamic zooming can be realized on the premise of not influencing the output capability of the laser.

The utility model discloses a quartz enhanced photoacoustic spectrometry gas detection system based on coaxial main and auxiliary resonance tubes, which comprises a signal generator, an adder, a laser, a collimator, a gas sensing device, a preamplifier, a lock-in amplifier, a data acquisition system and a computer, a laser is arranged on one side of the summator, a collimator is arranged at the output end of the laser, a gas sensing device is arranged on one side of the collimator, a pre-amplifier is arranged on the rear side of the gas sensing device, and the output end of the pre-amplifier is connected with the input end of the phase-locked amplifier. The output end of the lock-in amplifier is connected with the data acquisition system, and the data acquisition system is connected with the computer. The ultra-low trace gas detection device is used for ultra-low trace gas detection, gas concentration detection is rapid, accurate and effective, and the minimum detection limit of gas can be obviously enhanced.

The present invention is applicable to the field of pulsed laser technology and provides a pulsed laser modulation system. The system includes: a laser seed source for emitting a laser signal; a polarization-maintaining circulator having an incident end, a first emission end, and a second emission end, with the laser seed source and the incident end of the polarization-maintaining circulator being located on the same optical path; a fiber preamplifier and a laser pulse stretcher, with the first emission end, the fiber preamplifier, and the laser pulse stretcher being sequentially arranged on the same optical path; and an acousto-optic modulator and a fiber amplifier, with the second emission end, the acousto-optic modulator, and the fiber amplifier being sequentially arranged on the same optical path. The present invention proposes a design scheme for a pulsed laser modulation device that integrates stretching, preamplification, and frequency selection. By using this scheme, a low-repetition-rate pulsed laser output with a compact structure, good stability, and a high signal-to-noise ratio can be achieved.

A low-temperature dual-core synchronous magnetic resonance imaging radio frequency coil provided by the present invention comprises a radio frequency front-end circuit module and N single-channel low-temperature dual-core radio frequency coil units, each single-channel low-temperature dual-core radio frequency coil unit comprises a radio frequency coil layer, and the radio frequency coil layer is connected with a cold end face of a Peltier module through a heat conduction layer. The hot end face of the Peltier module is connected with the cooling module; the radio frequency coil layer comprises a radio frequency coil main body, the radio frequency coil main body is connected with a double-resonance tuning matching circuit, the double-resonance tuning matching circuit is connected with a transmitting-receiving change-over switch, and the transmitting-receiving change-over switch is respectively connected with a preamplifier and a radio frequency front-end circuit module; and the radio frequency front-end circuit module is loaded on the heat conduction layer of one single-channel low-temperature dual-core radio frequency coil unit. The radio frequency coil layer is in a low-temperature environment, the cost is low, the operation is easy, and electronic thermal noise is effectively inhibited; meanwhile, the single-channel low-temperature dual-core radio frequency coil unit forming the circularly polarized radio frequency field is an independent module and is convenient to repair and maintain.

This invention discloses a magnetoencephalogram (MEG) compatible preamplifier method and device, which allows the MEG preamplifier to be placed within a magnetically shielded device. This invention achieves weak magnetism in the preamplifier circuit through the design of component selection and distribution; improves anti-interference capability and transmission stability by designing the MEG amplification factor and signal conditioning process; implements secondary amplification, power supply, and acquisition outside the magnetically shielded device, placing strongly magnetic components away from the weak magnetic environment to complete the entire acquisition process; and adopts a modular design, reducing the number of channels on each circuit board by distributing electrode channels, thereby reducing the size and facilitating the arrangement of the preamplifier system within the limited magnetically shielded space. This invention achieves weak magnetism in the preamplifier circuit, enabling high-quality brain-computer magnetic synchronous acquisition when placed within a magnetically shielded space.

The application relates to the field of integrated circuit design, in particular to a double-tail dynamic comparator based on a feedback structure, which comprises a preamplifier, a latch and a positive feedback structure which are cascaded with each other; the preamplifier comprises input ends VIP and VIN, output ends fn and fp, and is used for amplifying comparison signals of the input ends; the latch is used for carrying out digital judgment on the amplified comparison signals and latching a judgment logic level; and the positive feedback structure is used for providing a discharge path for fn and fp and increasing a differential voltage between fn and fp. The application introduces the design of the positive feedback structure, adds a new discharge path to the output node of the amplifier to accelerate the pre-amplification speed, and increases the differential voltage between the output nodes fn and fp, so as to reduce the regeneration time of the latch, inhibit the influence of non-ideal factors on the comparator when the input differential signal is small, and accelerate the comparison speed.