CN-122026840-A - Regulating and controlling circuit for photoelectric detector signal

CN122026840ACN 122026840 ACN122026840 ACN 122026840ACN-122026840-A

Abstract

The application discloses a regulating and controlling circuit of a photoelectric detector signal, which relates to the field of photoelectric signals. The IV conversion module consists of a two-stage transimpedance operational amplification circuit, wherein a first-stage amplification module converts a photocurrent signal into a photovoltage signal, a second-stage amplification module carries out adjustable multiplying power secondary amplification on the voltage to realize high-fidelity amplification of the photovoltage signal and improve the subsequent processing precision, a frequency selection and frequency division module generates clock signals with different frequencies, a built-in 8ns frequency division unit realizes ns-stage signal detection, and a high-speed output module controls a switch to select an output channel according to the clock signals to output the complete waveform of the photovoltage signal, so that the stability of the output waveform is ensured, and the problem that the photovoltage signals with different high speeds cannot be accurately amplified and read is solved.

Inventors

SHAO YAN
ZHANG YUBO
XU JIACHEN
LIU ZIQI
WANG XIAOYI
WU XU

Assignees

北京理工大学

Dates

Publication Date: 20260512
Application Date: 20260130

Claims (10)

1. The regulating circuit of the photoelectric detector signal is characterized by comprising an IV conversion module, a frequency selection and division module and a high-speed output module; The IV conversion module comprises a primary amplification module and a secondary amplification module, wherein the primary amplification module is used for converting a photocurrent signal into a photovoltage signal, and the secondary amplification module is used for amplifying the photovoltage signal; The frequency dividing and selecting module comprises an 8ns frequency dividing unit, a 1us frequency dividing unit and a 1ms frequency dividing unit which are sequentially connected and is used for generating clock signals with different frequencies; The 8ns frequency dividing unit is used for receiving the photovoltage signal and outputting an on-chip clock signal of 125MHz, wherein the photovoltage signal corresponding to the on-chip clock signal of 125MHz is 8ns integer wave; the 1us frequency dividing unit is used for receiving the 125MHz on-chip clock signal and outputting a 1MHz on-chip clock signal, wherein the 1MHz on-chip clock signal corresponds to a 1us integer wave; the 1ms frequency dividing unit is used for receiving a 1MHz on-chip clock signal and outputting a 250kHz on-chip clock signal, dividing the 250kHz on-chip clock signal into a 1KHz on-chip clock signal, and the 1KHz on-chip clock signal corresponds to a 1ms integral wave. The high-speed output module is used for controlling the switch to select an output channel according to the clock signal and outputting an amplified photovoltage signal.
2. The regulation circuit of a photodetector signal according to claim 1, wherein said primary amplification module comprises a first transimpedance operational amplification circuit and said secondary amplification module comprises a second transimpedance operational amplification circuit; the first transimpedance operational amplifier circuit and the second transimpedance operational amplifier circuit both comprise a resistor structure and an operational amplifier, wherein the resistor structure is connected between the output end of the operational amplifier and the inverting input end of the operational amplifier in a bridging way; The resistor structure in the first transimpedance operational amplifier circuit comprises a rotary type selector switch and four groups of resistor-capacitor structures connected in series with the rotary type selector switch, wherein the resistor-capacitor structures comprise resistors and capacitors which are connected in parallel; The resistor structure in the second transimpedance operational amplifier circuit is a single resistor.
3. The circuit for modulating a photodetector signal according to claim 2, wherein said primary amplification module further comprises a radio frequency coaxial connector and a panel mounted SMA female socket; The radio frequency coaxial connector is connected with the panel-mounted SMA female socket, a rotary type selection switch in the first transimpedance operational amplifier circuit and an inverting input end of the first operational amplifier; The positive input end of the first operational amplifier is grounded through a resistor.
4. The regulation and control circuit of the photoelectric detector signal according to claim 2, wherein the inverting input end of the second operational amplifier in the second transimpedance operational amplifier circuit is connected with the output end of the primary amplifying module through a resistor; The output end of the secondary amplifying module is connected with the input end 1D of the high-speed output module.
5. The regulation circuit of a photodetector signal according to claim 1, wherein the output OUTN of the 8ns frequency dividing unit is connected with the input CLK of the 1us frequency dividing unit and the first switch, the output MR of the 1us frequency dividing unit is connected with the input CLK of the 1ms frequency dividing unit and the second switch, the output MR of the 1ms frequency dividing unit is connected with the third switch; The first switch, the second switch and the third switch are all connected with the CLK end of the input end of the high-speed output module.
6. The circuit for regulating and controlling a photodetector signal according to claim 5, wherein said high-speed output module is connected to two rf coaxial connectors via a 1S1 terminal for outputting an optical voltage signal.
7. The regulation and control circuit of the photodetector signal of claim 5, further comprising a step-up and step-down module and a battery management module; The battery management module mainly comprises an SP4533 chip, wherein a power MOSFET responsible for charging and a power MOSFET responsible for discharging are arranged in the SP4533 chip and are used for charging and discharging a regulating circuit of the photoelectric detector signal, and the output end of the battery management module is connected with the input end of the voltage boosting and reducing module.
8. The regulation and control circuit for the photodetector signal according to claim 7, wherein the step-up and step-down module comprises a step-up module and a step-down module, and an input end of the step-down module is connected with an output end of the step-up module.
9. The circuit for regulating and controlling the signal of the photoelectric detector according to claim 8, wherein the boosting module comprises a DC-DC converter, an inductor, a resistor, a capacitor and a diode; the inductor is connected across the DC-DC converter through an SW end and an IN end; The input end of the boosting module is connected with the EN end of the DC-DC converter through a first parallel circuit, and the first parallel circuit comprises a first capacitor, a second capacitor, a first resistor and a first diode which are connected in series; the other end of the first parallel circuit is grounded; The output end is connected with the SW end of the DC-DC converter through a second parallel circuit and a second diode, wherein the second parallel circuit comprises a third capacitor, a fourth capacitor and three resistors connected in series, and the three resistors connected in series comprise a second resistor, a third resistor and a fourth resistor; The other end of the second parallel circuit is grounded; and the FB end of the DC-DC converter is respectively connected with the second resistor and the third resistor, and the GND end of the DC-DC converter is grounded.
10. The circuit for regulating and controlling the signals of the photoelectric detector according to claim 7, wherein the voltage boosting module performs voltage boosting treatment on the voltage output by the power management module, and then performs voltage reducing treatment through the first voltage reducing module, so as to supply power to the primary amplifying module and the secondary amplifying module; The voltage boosting module is also used for outputting the voltage subjected to primary voltage reduction through the second voltage reduction module in a reverse voltage mode or performing secondary voltage reduction on the voltage subjected to primary voltage reduction through the third voltage reduction module.

Description

Regulating and controlling circuit for photoelectric detector signal Technical Field The application relates to the field of photoelectric signals, in particular to a regulating circuit of a photoelectric detector signal. Background Photodetectors are a class of sensing devices that utilize the photoelectric effect to convert incident optical radiation energy into a measurable electrical signal. The photoelectric detection circuit is used as an important component, and has the key effects of detecting weak electric signals generated by the photosensitive element, further amplifying, filtering, shaping and the like the signals, and finally outputting the signals which can be used for subsequent analysis, control or display. The current photoelectric detector manufacturing has realized high CMOS process compatibility, silicon or silicon on insulator SOI is used as a substrate, a light absorption region, a PIN junction and a high-speed electrode are integrated at one time through three steps of epitaxy, etching and metallization, a mature fixing scheme is formed corresponding to an infrared front-end photoelectric detection circuit, and a 'board-level' circuit carried on a PCB board takes a 10 kHz-50 MHz frequency band to effectively amplify nA-level photocurrent to a V-level as a core target, and simultaneously noise, parasitic interference and temperature drift influence are furthest suppressed. The OPA657 or the self-grinding SiGe bare chip is selected as a transimpedance operational amplifier circuit TIA to complete IV conversion, then a second-order active low-pass filter is cascaded, a differential driver (such as THS4541 and a same-level device) is connected, and finally an analog signal is output through an SMA interface; if digital output is needed, an analog-to-digital converter and an FPGA module can be additionally arranged at the tail end of the link to realize digital processing. In addition, the low-cost scheme can adopt a single power supply architecture, uses an LM358 or TL081 single chip and a PIN tube as a core, and can realize stable detection of 200kHz frequency band and 1 mu W level visible light signals only by 5V power supply. With the development of infrared systems to high frame rate imaging, high-speed laser ranging, active infrared modulation and the like, the modulation frequency of infrared photoelectric signals has been increased from the traditional kHz level to tens of MHz (corresponding to tens of ns level) to the GHz level (corresponding to hundreds of ps level). However, when the board-level infrared photoelectric detection circuit amplifies high-frequency signals, the board-level infrared photoelectric detection circuit is limited by multiple factors such as insufficient intrinsic bandwidth of the detector, board-level parasitic parameters, gain-bandwidth bottleneck of a front-end amplifier, EMI interference, impedance mismatch and the like, so that the high-frequency infrared signals cannot be amplified in a fidelity manner. At the packaging level of 'board level', infrared modulation signals exceeding 500MHz simultaneously need low-capacitance detectors, zero parasitic interconnection, 50 omega matching, nA-level low-noise amplification and multi-pixel parallel readout, and no commercial or verification board level scheme can break through at the same time at present. Therefore, the board-level infrared photoelectric detection circuit in the current stage can only see high-frequency signals, but cannot realize fidelity amplification on the premise of not losing sensitivity, dynamic range or pixel scale, which is the biggest practical obstacle of a high-speed infrared sensing system, and the circuit can be broken through by means of device miniaturization, packaging optimization, integrated front-end circuit design and the like. The existing photoelectric detector signal regulating and controlling circuit only supports ms-us level signal detection, infrared light with the frequency in ns level is difficult to detect, the problem that the existing photoelectric signal amplifier cannot realize ns level signal detection exists, in addition, the regulating and controlling circuit is generally designed for a specific frequency, the frequency adjustability and the detection convenience are poor, particularly, high-adaptability matching is difficult to achieve for detection of high-speed photoelectric signals with different frequencies, high-precision amplification reading cannot be achieved, the regulating and controlling circuit is generally integrated on a special photoelectric signal detecting instrument, the regulating and controlling circuit cannot be independently used, the volume and the weight are large, and the cost is generally high. Along with the development of the existing photoelectric detector in the directions of miniaturization, light weight and low cost, the invention has important significance in the high-precision amplifying and reading circuit and technology