7 results about "Cascade amplifier" patented technology

The embodiment of the present disclosure provides a low-offset circuit structure with a cascade amplifier, comprising: an amplification link comprising cascaded amplifiers, a first-stage amplifier for receiving a radio frequency input signal, and a last-stage amplifier for outputting a radio frequency output signal; a rectifier comprising a first input end and a second input end, connected with a non-inverting output end and an inverting output end of the amplifier respectively, and outputting a detection signal; a calibration circuit comprising a logic circuit, connected with an output end of the rectifier, generating a target calibration signal based on a detected offset voltage and an initial calibration signal, and when the detected offset voltage reaches a preset value, a corresponding initial calibration signal is used to determine the target calibration signal; the calibration circuit further comprises a current output unit for outputting a compensation current to a second target amplifier based on the target calibration signal. The embodiment of the present disclosure can reduce the offset voltage of the circuit structure and improve the stability and dynamic response performance of the circuit.

The invention relates to the technical field of electrophysiological signal recording and stimulation of cerebral neurons, in particular to a distributed electrophysiological signal recording and stimulation system for cerebral neurons. The system comprises a recording path and a stimulation path, wherein the recording path is composed of an analog switch, a multi-stage cascade amplifier, a plurality of analog-to-digital converters, an FPGA main control board and a computer, and electrophysiological signals are collected and uploaded; the stimulation channel is composed of the computer, the FPGA main control board, a digital-to-analog converter and the analog switch and is used for issuing an electrical stimulation signal; wherein the amplifier, the converter and the power supply module are integrated on an independent PCB (Printed Circuit Board) and are connected with the FPGA main control board through an FMC (Frequency Management Controller) interface. The system configures the oversampling multiplying power of the analog-to-digital converter through the FPGA main control board so as to optimize the actual sampling rate and the signal-to-noise ratio. According to the invention, integration of acquisition and stimulation functions, hardware modularization and dynamic adjustment of signal quality are realized, and the flexibility and signal fidelity of the system are improved.

This invention discloses a low-noise amplifier and receiving system. The low-noise amplifier includes: an input matching circuit, a primary circuit, an interstage matching circuit, a secondary circuit, an output matching circuit, and a common bias circuit. The input matching circuit is connected to the primary circuit and the common bias circuit; the interstage matching circuit is connected to the primary circuit and the secondary circuit; the secondary circuit is connected to the common bias circuit and the output matching circuit; the common bias circuit is connected to a power supply; and the power supply voltage is connected to the primary circuit and the secondary circuit. For the primary and secondary amplifier circuits used to amplify signals, the active bias structure of the common bias circuit effectively reduces the number of components in the multi-stage cascaded amplifier circuit, thereby reducing the overall chip area and mitigating the coupling and parasitic risks caused by component layout and wiring within a limited layout area.

This 2μm single-frequency pulsed laser, based on synchronous modulation and solid-state graded-doping, comprises a fiber-optic synchronous modulation cascaded amplifier and a solid-state non-uniformly graded-doped two-way amplifier. Synchronous modulation in the fiber section suppresses noise, improving the signal-to-noise ratio and solid-state amplification efficiency. The non-uniformly graded-doped gain crystal group in the solid-state section enables small-signal amplification, high-energy extraction, and high amplification efficiency. This allows for high-efficiency, high-repetition-rate, high-energy, narrow-linewidth pulsed laser output in the tens to hundreds of millijoules range, significantly improving the detection accuracy and capability of radar systems.

The application discloses a light source device, a system and a water window band full-coherent free electron laser generating method. The device comprises: a harmonic generation unit for connecting an electron beam and a seed laser and generating low-order harmonics; at least two cascaded amplifier units connected with the harmonic generation unit, for connecting the low-order harmonic radiation and generating coherent harmonic radiation, and for tuning the coherent harmonic laser to high-order harmonic radiation to obtain water window band full-coherent free electron laser pulses. The application constructs a multi-stage amplifier unit in the rear stage of the harmonic generation unit, and each subsequent amplifier unit is configured to resonate on a high-order harmonic of the radiation output by the previous amplifier unit, so that the harmonic radiation of the previous stage is used as the effective seed of the subsequent stage, the frequency is up-converted stage by stage, the frequency of the coherent radiation is converted to the target high-order harmonic stage by stage, and the water window band full-coherent free electron laser is obtained.

An amplifier circuit comprises a multi-stage amplifier having a plurality of amplifiers cascaded between an input port Vin and an output port Vout to form a differential input stage and N subsequent gain stages, a capacitive load CL coupled to the output port Vout, and a compensation network coupled to the multi-stage amplifier and configured for positioning Pole-Zero pairs of each stage of the multi-stage amplifier below a unity gain frequency ωt of the multi-stage amplifier when compensated, with Zeros positioned lower than Poles so as to increase the unity gain frequency ωt.

The invention discloses a light source device, a light source system and a water window wave band full-coherence free electron laser generation method. The device comprises a harmonic generation unit used for accessing an electron beam and seed laser and generating low-order harmonics; and the at least two stages of cascaded amplifier units are connected with the harmonic generation unit, and are used for accessing low-order harmonic radiation, generating coherent harmonic radiation and tuning the coherent harmonic laser into high-order harmonic radiation so as to obtain the water window wave band full-coherent free electron laser pulse. According to the invention, the multi-stage amplifier units are constructed at the rear stage of the harmonic generation unit, and each subsequent amplifier unit is configured to resonate on a higher harmonic output and radiated by the previous amplifier unit, so that the harmonic radiation of the previous stage is used as an effective seed of the next stage, and the step-by-step up-conversion of the frequency is realized; and converting the frequency of the coherent radiation to a target higher harmonic step by step to obtain the water window wave band full-coherent free electron laser.