Particle radiation detector readout circuit and detection system

Abstract

Embodiments of the present specification provide a particle radiation detector readout circuit and a detection system, wherein the readout circuit is adapted to be coupled with a particle radiation detector, and includes a buffer module and a readout module, wherein: the buffer module includes a plurality of output channels, is coupled between an output end of the particle radiation detector and the readout module, and is adapted to transmit an output signal of the particle radiation detector from a corresponding output channel to the readout module; and the readout module includes a plurality of readout channels, is coupled with the plurality of output channels one by one, and is adapted to output a particle radiation detection result based on the output signal of the particle radiation detector. With the above scheme, high-precision particle radiation detection can be achieved while taking into account particle radiation detection in different energy ranges and matching particle radiation detectors with different capacitances.

Description

TECHNICAL FIELD

[0001] Embodiments of the present specification relate to the technical field of space particle radiation detection, and in particular to a particle radiation detector readout circuit and a detection system. BACKGROUND

[0002] Particle radiation detector readout application specific integrated circuits are widely used due to their high performance and low resource consumption.

[0003] However, since the energy detection range and the optimal input detector capacitance of the existing particle radiation detector readout application specific integrated circuits are fixed and cannot be directly changed, they cannot be applied to particle radiation detection in different energy ranges and cannot match particle radiation detectors with different capacitances. SUMMARY

[0004] Therefore, embodiments of the present specification provide a particle radiation detector readout circuit and a detection system, which can achieve high-precision particle radiation detection while taking into account particle radiation detection in different energy ranges and matching particle radiation detectors with different capacitances.

[0005] First, embodiments of the present specification provide a particle radiation detector readout circuit adapted to be coupled with a particle radiation detector, comprising a buffer module and a readout module, wherein:

[0006] The buffer module comprises a plurality of output channels coupled between the output end of the particle radiation detector and the readout module, and is adapted to transmit the output signal of the particle radiation detector from the corresponding output channel to the readout module;

[0007] The readout module comprises a plurality of readout channels corresponding to the plurality of output channels, and is adapted to output a particle radiation detection result based on the output signal of the particle radiation detector.

[0008] Optionally, the buffer module comprises a buffer unit and a channel expansion unit, wherein:

[0009] The buffer unit is coupled with the output end of the particle radiation detector and is adapted to read out the output signal of the particle radiation detector;

[0010] The channel expansion unit comprises a plurality of output channels and is adapted to transmit the output signal of the buffer unit from the corresponding output channel to the readout module.

[0011] Optionally, the buffer unit comprises:

[0012] a junction field effect transistor, the gate of which is coupled with the output end of the particle radiation detector, the drain of which is coupled with a power supply, and the source of which is coupled with the channel expansion unit;

[0013] a bias resistor coupled between the power supply and the drain of the junction field effect transistor.

[0014] Optionally, the channel expansion unit comprises:

[0015] a plurality of channel resistors, each channel resistor connected in series between the source of the junction field effect transistor and the ground;

[0016] a plurality of output channels, each output channel disposed between a corresponding channel resistor and a readout channel.

[0017] Optionally, the resistance of at least some of the plurality of channel resistors is adjustable.

[0018] Optionally, the buffer module further comprises:

[0019] a coupling capacitor coupled between a corresponding channel resistor and the readout channel.

[0020] Optionally, the coupling capacitor has a capacitance greater than that of the particle radiation detector.

[0021] Optionally, the readout module comprises a readout channel; the readout channel comprises an amplification unit and a feedback unit, wherein:

[0022] the amplification unit is disposed in the corresponding readout channel and is adapted to amplify a signal output by the corresponding output channel;

[0023] the feedback unit is coupled between the output terminal and the input terminal of the amplification unit and is adapted to output a particle radiation detection result based on the signal output by the output channel.

[0024] Optionally, the amplification unit comprises a charge-sensitive amplifier.

[0025] Optionally, the feedback unit comprises a feedback resistor and a feedback capacitor, wherein:

[0026] the feedback resistor is connected in parallel with the charge-sensitive amplifier;

[0027] the feedback capacitor is connected in parallel with the charge-sensitive amplifier.

[0028] The embodiments of the present specification also provide a particle radiation detection system, comprising:

[0029] a particle radiation detector adapted to detect particle radiation energy;

[0030] a particle radiation detector readout circuit coupled to the particle radiation detector and adapted to employ the readout circuit of any one of the preceding embodiments.

[0031] The control module is coupled with the particle radiation detector readout circuit and is adapted to control the particle radiation detector readout circuit to read the output signal of the particle radiation detector through the readout channel matched with the range and output a particle radiation detection result based on the output signal of the particle radiation detector.

[0032] Optionally, the particle radiation detector readout circuit comprises a buffer module and a readout module, the buffer module comprises a buffer unit and a channel expansion unit, wherein the buffer unit is coupled with the output end of the particle radiation detector and is adapted to read the output signal of the particle radiation detector; the channel expansion unit comprises a plurality of output channels and is adapted to transmit the output signal of the buffer unit from the corresponding output channel to the readout module.

[0033] The particle radiation detector and the buffer unit of the particle radiation detector readout circuit are coupled through a wire.

[0034] The particle radiation detector readout circuit provided by the embodiment of the present specification is adapted to be coupled with a particle radiation detector and comprises a buffer module and a readout module, wherein the buffer module comprises a plurality of output channels and is coupled between the output end of the particle radiation detector and the readout module, the output signal of the particle radiation detector is transmitted from the corresponding output channel to the readout module through the buffer module, which can prevent impedance / capacitive impedance mismatch between the particle radiation detector and the readout module; the readout module comprises a plurality of readout channels and is coupled with the plurality of output channels one by one, based on the energy size of the output signal of the particle radiation detector, a corresponding output channel is selected, and then a particle radiation detection result is output through the readout channel coupled with the output channel, so that high-precision particle radiation detection can be realized while taking into account particle radiation detection in different energy ranges and matching particle radiation detectors with different capacitances.

[0035] Further, the buffer module can comprise a buffer unit and a channel expansion unit, wherein the buffer unit is coupled with the output end of the particle radiation detector and reads the output signal of the particle radiation detector through the buffer unit, which can prevent impedance / capacitive impedance mismatch between the particle radiation detector and the readout module; the channel expansion unit comprises a plurality of output channels and transmits the output signal of the buffer unit from the corresponding output channel to the readout module, which can perform particle radiation detection in different energy ranges, so that the readout circuit can be unsaturated when performing particle radiation detection in a large energy range and has high precision when performing particle radiation detection in a small energy range.

[0036] Further, the buffer unit can include a junction field effect tube source and a bias resistor, wherein a gate of the junction field effect tube source is coupled with an output end of the particle radiation detector, a drain thereof is coupled with a power supply, and a source thereof is coupled with the channel expansion unit; the bias resistor is coupled between the power supply and the drain of the junction field effect tube source, and the output signal of the particle radiation detector is converted by the junction field effect tube and output, which can prevent impedance / capacitive impedance mismatch between the particle radiation detector and the readout module, thereby improving the accuracy of the particle radiation detection result. In addition, by adjusting the junction capacitance of the junction field effect tube, the problem of capacitance mismatch between the particle radiation detector and the readout circuit can also be avoided.

[0037] Further, the channel expansion unit can include a plurality of channel resistors and a plurality of output channels, wherein each channel resistor is connected in series between the source of the junction field effect tube and the ground; each output channel is arranged between the corresponding channel resistor and the readout channel, and the output signal of the particle radiation detector is transmitted from the corresponding output channel to the readout channel coupled with the output channel through the channel resistor, which has a simple structure, is easy to implement, and is conducive to the detection and maintenance of the readout circuit.

[0038] Further, by adjusting the resistance value of at least part of the plurality of channel resistors, the energy detection range of each readout channel can be adjusted, thereby increasing the flexibility of the readout circuit, realizing particle radiation detection in different energy ranges, and through the readout channel with a smaller energy detection range, higher resolution can be obtained, and through the readout channel with a larger energy detection range, saturation can be prevented when performing particle radiation detection in a large energy range.

[0039] Further, the buffer module can also include a coupling capacitor coupled between the corresponding channel resistor and the readout channel, and by the coupling capacitor, the range of the readout channel can be adjusted, and thereby the sensitivity of the readout circuit of the particle radiation detector can be adjusted, thereby further improving the accuracy of the particle radiation detection result.

[0040] Further, by setting the capacitance of the coupling capacitor to be greater than the capacitance of the particle radiation detector, the readout circuit can more easily obtain the particle radiation detection result, and the performance of the readout circuit can be improved.

[0041] Further, the readout channel can include an amplification unit and a feedback unit, wherein the amplification unit is arranged in the corresponding readout channel, and the signal output by the corresponding output channel can be amplified by the amplification unit; the feedback unit is coupled between the output end and the input end of the amplification unit, and is adapted to output the particle radiation detection result based on the signal output by the output channel, which has a simple structure, is easy to implement, and is conducive to the detection and maintenance of the readout circuit.

[0042] Further, the feedback unit can include a feedback resistor and a feedback capacitor, wherein the feedback resistor is connected in parallel with the charge sensitive amplifier; and the feedback capacitor is connected in parallel with the charge sensitive amplifier, so that a signal output particle radiation detection result can be realized based on the signal output by the output channel. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the provided drawings.

[0044] Figure 1 A structure schematic diagram of a particle radiation detector readout circuit in an embodiment of the present application is shown;

[0045] Figure 2 A structure schematic diagram of another particle radiation detector readout circuit in an embodiment of the present application is shown;

[0046] Figure 3 A specific structure schematic diagram of a particle radiation detector readout circuit in an embodiment of the present application is shown;

[0047] Figure 4 A principle structure schematic diagram of a particle radiation detector readout circuit in an embodiment of the present application is shown;

[0048] Figure 5 A structure schematic diagram of a readout channel in an embodiment of the present application is shown;

[0049] Figure 6 An output voltage amplitude and particle radiation detector capacitance relationship schematic diagram of a particle radiation detector readout circuit in an embodiment of the present application is shown;

[0050] Figure 7 An output voltage amplitude and coupling capacitance relationship schematic diagram of a particle radiation detector readout circuit in an embodiment of the present application is shown;

[0051] Figure 8 An output voltage amplitude schematic diagram of a particle radiation detector readout circuit under different particle radiation detector capacitances in an embodiment of the present application is shown;

[0052] Figure 9 An output voltage amplitude schematic diagram of a particle radiation detector readout circuit in an embodiment of the present application is shown;

[0053] Figure 10 A structural schematic diagram of a particle radiation detection system in an embodiment of the present specification is shown.

[0054] Figure 11 A structural schematic diagram of a particle radiation detection system in an embodiment of the present specification is shown.

[0055] Figure 12 A structural schematic diagram of a particle radiation detection system in an embodiment of the present specification is shown.

[0056] Figure 13 A structural schematic diagram of a particle radiation detection system in an embodiment of the present specification is shown. DETAILED DESCRIPTION

[0057] As described in the background, particle radiation detector readout application specific integrated circuits (ASICs) are widely used due to their high performance and low resource consumption. However, the energy detection range and the optimal input detector capacitance of the existing particle radiation detector readout application specific integrated circuits are fixed and cannot be directly changed, so they cannot be applied to particle radiation detection in different energy ranges and cannot match particle radiation detectors with different capacitances.

[0058] For example, the Readout Electronics for Nuclear Applications (RENA-3) is a 36-channel charge-sensitive amplifier / shaper integrated circuit with a trigger output, which is a monolithic integrated circuit developed specifically for X-ray and gamma-ray detection in various applications such as space physics research and medical imaging. The maximum input signal charge of RENA3 is 54fC, corresponding to an energy detection range of 1.2MeV in a silicon detector, and its optimal input detector capacitance is 2pF or 9pF, which is only suitable for small-area thick detectors.

[0059] RENA-3 is selected for the Interplanetary Ultra-Low Noise Three-Dimensional High-Energy Particle Instrument, which is used to detect interplanetary energetic electrons and protons. The instrument contains a set of 4-layer x 5-pixel silicon semiconductor detector arrays. The thicknesses of the 4-layer detectors are 100um, 500um, 500um, and 300um, respectively, each layer having 5 pixels with an area of about 1cm 2RENA-3 can cover the electron channel energy detection range of the instrument with a maximum deposition energy of about 1 MeV. However, it cannot meet the energy detection range requirement of detecting protons, with a maximum deposition energy of about 12 MeV. Therefore, for proton detection, the detectable energy range must be expanded by at least ten times. In addition, the high detector capacitance (up to tens or even hundreds of pF) does not match the optimal input capacitance of 2 pF or 9 pF of RENA-3.

[0060] To solve the above problems, an embodiment of the present specification provides a particle radiation detector readout circuit adapted to be coupled with a particle radiation detector, comprising a buffer module and a readout module, wherein the buffer module comprises a plurality of output channels coupled between the output end of the particle radiation detector and the readout module, and the output signal of the particle radiation detector is transmitted from the corresponding output channel to the readout module through the buffer module, which can prevent impedance / capacitance mismatch between the particle radiation detector and the readout module; the readout module comprises a plurality of readout channels corresponding to the plurality of output channels, and based on the energy size of the output signal of the particle radiation detector, the corresponding output channel is selected, and then the particle radiation detection result is output through the readout channel coupled with the output channel, so that high-precision particle radiation detection can be realized while considering particle radiation detection in different energy ranges, and the mismatch problem between the optimal input capacitance (2 pF or 9 pF) of RENA-3 and the detector capacitance (up to tens or even hundreds of pF) is solved.

[0061] In order for those skilled in the art to better understand and implement the embodiments of the present specification, the concepts, schemes, principles and advantages of the embodiments of the present specification are described in detail below with reference to the drawings and through specific application examples.

[0062] First, the present specification provides a particle radiation detector readout circuit, referring to Figure 1 a structure diagram of a particle radiation detector readout circuit, the particle radiation detector readout circuit A is adapted to be coupled with a particle radiation detector D, which can include a buffer module A1 and a readout module A2, wherein:

[0063] The buffer module A1 comprises a plurality of output channels A111-A11n coupled between the output end of the particle radiation detector and the readout module A2, and is adapted to transmit the output signal of the particle radiation detector D from the corresponding output channel to the readout module A2;

[0064] The readout module A2 comprises a plurality of readout channels A211-A21n corresponding to the plurality of output channels A111-A11n, and is adapted to output the particle radiation detection result based on the output signal of the particle radiation detector D.

[0065] The particle radiation detector readout circuit can select the corresponding output channel A111-A11n based on the energy of the output signal of the particle radiation detector D, and then output the particle radiation detection result through the readout channel A211-A21n coupled with the output channel A111-A11n, so that the particle radiation detection with high precision can be realized while considering the particle radiation detection in different energy ranges and matching the particle radiation detector with different capacitances.

[0066] To enable those skilled in the art to better understand and implement the present application, the specific structure of the buffer module is described below through some specific examples.

[0067] In a specific implementation, referring to the structure schematic diagram of another particle radiation detector readout circuit shown in FIG. 2, the buffer module A1 can include a buffer unit A12 and a channel expansion unit A13, wherein: Figure 2

[0068] The buffer unit A12 is coupled with the output end of the particle radiation detector and is adapted to read out the output signal of the particle radiation detector.

[0069] The channel expansion unit A13 includes a plurality of output channels A111-A11n and is adapted to transmit the output signal of the buffer unit from the corresponding output channel A111-A11n to the readout module A2.

[0070] The particle radiation detector readout circuit can prevent the impedance / capacitive impedance mismatch between the particle radiation detector and the readout module A2 by reading out the output signal of the particle radiation detector through the buffer unit A12, and can perform particle radiation detection in different energy ranges by transmitting the output signal of the buffer unit A12 from the corresponding output channel A111-A11n to the readout module A2 through the channel expansion unit A13, so as to ensure that the readout circuit is not saturated when performing particle radiation detection in a large energy range, and the readout circuit has high precision when performing particle radiation detection in a small energy range.

[0071] In some embodiments of the present application, the buffer unit A12 can include:

[0072] a junction field effect transistor, the gate of which is coupled with the output end of the particle radiation detector, the drain of which is coupled with the power supply, and the source of which is coupled with the channel expansion unit;

[0073] a bias resistor, which is coupled between the power supply and the drain of the junction field effect transistor.

[0074] ​By using the above-mentioned embodiments, the output signal of the particle radiation detector is converted and output by the junction field-effect transistor, so that impedance / mismatch between the particle radiation detector and the readout module can be prevented, thereby improving the accuracy of the particle radiation detection result. In addition, by adjusting the junction capacitance of the junction field-effect transistor, the problem of capacitance mismatch between the particle radiation detector and the readout circuit can also be avoided.

[0075] As a specific example, refer to Figure 3 a specific structure diagram of a particle radiation detector readout circuit shown in FIG. 1, wherein the buffer unit of the particle radiation detector readout circuit A includes:

[0076] a P-channel junction field-effect transistor (JFET) whose gate G is coupled to the output end of the particle radiation detector, whose drain D is coupled to the power supply VDD, and whose source S is coupled to the channel expansion unit;

[0077] a bias resistor R1 coupled between the power supply VDD and the drain D of the P-channel junction field-effect transistor JFET.

[0078] By using the above-mentioned embodiments, the charge signal output by the particle radiation detector is integrated on the equivalent input capacitance of the gate G of the P-channel junction field-effect transistor JFET, which converts the charge into voltage in the P-channel junction field-effect transistor JFET, and a low-impedance output signal is obtained at the source S of the P-channel junction field-effect transistor JFET. Therefore, impedance mismatch between the particle radiation detector and the readout module can be prevented, thereby improving the accuracy of the particle radiation detection result. In addition, by adjusting the junction capacitance of the P-channel junction field-effect transistor to match the capacitance of the particle radiation detector, the problem of capacitance mismatch between the particle radiation detector and the readout circuit can also be avoided.

[0079] It can be understood that the type of the junction field-effect transistor is not limited in the embodiments of the present specification, and in specific implementations, an N-channel junction field-effect transistor can also be used.

[0080] In some embodiments of the present specification, the channel expansion unit A13 can include:

[0081] a plurality of channel resistors, each of which is connected in series between the source of the junction field-effect transistor and the ground;

[0082] a plurality of output channels, each of which is arranged between a corresponding channel resistor and a readout channel.

[0083] The above embodiment transmits the output signal of the particle radiation detector from the corresponding output channel to the readout channel coupled with the output channel through the channel resistance, which is simple in structure, easy to implement, and conducive to the detection and maintenance of the readout circuit.

[0084] As a specific example, continuing to refer to Figure 3 , the channel expansion unit of the particle radiation detector readout circuit A can include:

[0085] a channel resistance R2, a first end of which is coupled to the source S of the P-channel junction field effect transistor JFET;

[0086] a channel resistance R3, a first end of which is coupled to a second end of the channel resistance R2, and a second end of which is coupled to the ground;

[0087] an output channel CH1, coupled between the first end of the channel resistance R2 and the corresponding readout channel;

[0088] an output channel CH2, coupled between the first end of the channel resistance R3 and the corresponding readout channel.

[0089] The above embodiment divides the output of the P-channel junction field effect transistor JFET into two outputs through the channel resistance R2 and the channel resistance R3, one of which is transmitted from the output channel CH1 to the readout channel coupled with the output channel CH1, and the other of which is transmitted from the output channel CH2 to the readout channel coupled with the output channel CH2, and the two readout channels correspond to different energy detection ranges respectively, which is simple in structure, easy to implement, and conducive to the detection and maintenance of the readout circuit.

[0090] It can be understood that the number of output channels included in the channel expansion unit of the embodiments of the present specification is not specifically limited, as long as a corresponding channel resistance is provided for each output channel.

[0091] In some embodiments of the present specification, the buffer module can further include a coupling capacitor coupled between the corresponding channel resistance and the readout channel, through which the range of the readout channel can be adjusted, and thus the sensitivity of the particle radiation detector readout circuit can be adjusted, so as to further improve the accuracy of the particle radiation detection result.

[0092] Specifically, when the coupling capacitor is the same as the capacitance of the particle radiation detector, the sensitivity of the particle radiation detector readout circuit remains unchanged; when the coupling capacitor is greater than the capacitance of the particle radiation detector, the range of the readout channel can be shortened, and the sensitivity of the particle radiation detector readout circuit can be increased.

[0093] As a specific example, referring to Figure 4A schematic diagram of a principle structure of a readout circuit of a particle radiation detector is shown, wherein a capacitor C D is connected in parallel with a current generator i D as a theoretical model of a particle radiation detector and is biased by a bias resistor R b . When a particle injects into the particle radiation detector, the particle radiation detector outputs a charge amount Q in . C gs is a gate-source junction capacitance of a P-channel junction field effect transistor (JFET), C gd is a gate-drain junction capacitance of the P-channel JFET, g m is a transconductance of the P-channel JFET. The resistor R1 is used to bias the P-channel JFET. The output of the source of the JFET (JFET SF) is split into two outputs by resistors R2 and R3. One output is ac-coupled to a charge-sensitive amplifier (CSA) CSA1 through a coupling capacitor C n1 , C f1 and R f1 are a feedback capacitor and a resistor of the CSA1, and the other output is ac-coupled to a charge-sensitive amplifier (CSA) CSA2 through a coupling capacitor C n2 , C f2 and R f2 are a feedback capacitor and a resistor of the CSA2. The charge amount Q in generated when a particle injects into the particle radiation detector is integrated on the capacitance of the input of the P-channel JFET, and then discharged through an RC equivalent circuit of the input node. R is an equivalent resistance at the node through which a leakage current flows. C = C D + C gd + C gs is the total capacitance seen by the input. The feature of this configuration is that the output resistance is low, which can drive a higher load, including a capacitive load, thereby allowing a longer connection between the P-channel JFET output and the CSA input, making the design of the readout circuit more flexible and more stable. The readout circuit using the P-channel JFET can also be applied to a large-area detector with a high junction capacitance.

[0094] The amplification A1 is defined as the ratio of U sf and Q in (input charge of the JFET), wherein U sf represents the change of the source output of the source of the P-channel JFET, and Q in represents the input charge of the P-channel JFET, and then there is:

[0095]

[0096] When g m (R2+R3)>>1, then:

[0097]

[0098] The output charge of the coupling capacitor C n1 , i.e. the input charge of the charge sensitive amplifier CSA1 is defined as Q out1 , which is expressed as:

[0099]

[0100] where Q out1 is proportional to the input charge signal Q in . However, the gain of the P-channel junction field effect transistor JFET is not strictly equal to 1 in practice, so there is a deviation from the ideal output. The signal is amplified by a factor of C n1 / (C D +C gd ), which can be amplified by choosing a large coupling capacitor C n1 . The signal can be amplified by the P-channel junction field effect transistor JFET, thereby obtaining a higher amplitude signal that is less sensitive to interference and removes noise. By increasing the value of the coupling capacitor C n1 , the effective input capacitance of the charge sensitive amplifier CSA1 and the influence of the wire stray capacitance can also be reduced, so that longer wires can be used between the P-channel junction field effect transistor JFET and the charge sensitive amplifier CSA, making the design of the readout circuit more flexible and stable.

[0101] It can be understood that each output of the P-channel junction field effect transistor JFET source has the same principle, which will not be repeated here.

[0102] As a specific example, continuing to refer to Figure 3 , the buffer module of the particle radiation detector readout circuit A further includes:

[0103] a coupling capacitor C n1 coupled between the channel resistor R2 and the corresponding readout channel;

[0104] a coupling capacitor C n2 coupled between the channel resistor R3 and the corresponding readout channel.

[0105] In specific implementations, the coupling capacitor C n1 and / or the coupling capacitor C n2The value of the resistance can change the range of the corresponding readout channel, and when the coupling capacitance is greater than the capacitance of the particle radiation detector, the range of the corresponding readout channel can be shortened, the sensitivity of the readout circuit of the particle radiation detector is increased, and therefore the accuracy of the particle radiation detection result can be further improved.

[0106] In specific implementation, the resistance of at least part of the plurality of channel resistances is adjustable. By adjusting the resistance of at least part of the plurality of channel resistances, the energy detection range of each readout channel can be adjusted, the flexibility of the readout circuit can be increased, particle radiation detection in different energy ranges can be realized, higher resolution can be obtained through a readout channel with a smaller energy detection range, and saturation can be prevented when particle radiation detection in a large energy range is performed through a readout channel with a larger energy detection range.

[0107] It can be understood that the energy detection range of each readout channel is not specifically limited in the embodiments of the present specification.

[0108] Specifically, continuing to refer to Figure 4 , the output of the source of the P-channel junction field effect transistor JFET is divided into two outputs U sf and U2 through the resistance R2 and the resistance R3.

[0109] U2 can be expressed as:

[0110]

[0111] When C n1 =C n2 =C n , there is:

[0112]

[0113] As can be seen from the above formula, the resistance R2 and the resistance R3 can be adjusted to expand the energy detection range of the corresponding readout channel, the flexibility of the readout circuit can be increased, particle radiation detection in different energy ranges can be realized, higher resolution can be obtained through a readout channel with a smaller energy detection range, and saturation can be prevented when particle radiation detection in a large energy range is performed through a readout channel with a larger energy detection range. For example, for RENA-3 used in an interplanetary ultra-low noise three-dimensional high-energy particle instrument, if the particle deposition energy is less than 1.2 MeV, the original channel Q out1 with higher resolution can be used; and if the particle deposition energy is greater than 1.2 MeV, the range expansion channel Q out2 is used to ensure that the output is not saturated.

[0114] In specific implementations, the coupling capacitor can have a capacitance greater than that of the particle radiation detector, so that the readout circuit can more easily obtain particle radiation detection results and improve performance of the readout circuit.

[0115] In some embodiments of the present disclosure, referring to Figure 5 FIG. 2 shows a structure schematic diagram of a readout channel, the readout module A2 includes readout channels A21-A2n; the readout channel A2n includes an amplification unit M2n and a feedback unit F2n, wherein:

[0116] The amplification unit M2n is disposed in the corresponding readout channel and is adapted to amplify a signal output by the corresponding output channel;

[0117] The feedback unit F2n is coupled between the output end and the input end of the amplification unit M2n and is adapted to output a particle radiation detection result based on the signal output by the output channel.

[0118] With the above embodiments, the amplification unit M2n can amplify the signal output by the corresponding output channel; the feedback unit F2n can output a particle radiation detection result based on the signal output by the output channel, which is simple in structure and easy to implement, and is conducive to detection and maintenance of the readout circuit.

[0119] In some embodiments of the present disclosure, continuing to refer to Figure 3 , the amplification unit of the particle radiation detector readout circuit A can include a charge-sensitive amplifier.

[0120] In some other embodiments of the present disclosure, continuing to refer to Figure 3 For ease of description, the readout channel coupled with the output channel CH1 is taken as an example for description, the feedback unit of the particle radiation detector readout circuit A can include a feedback resistor R f1 and a feedback capacitor C f1 , wherein:

[0121] The feedback resistor R f1 is connected in parallel with the charge-sensitive amplifier CSA1.

[0122] The feedback capacitor C f1 is connected in parallel with the charge-sensitive amplifier CSA1.

[0123] With the above embodiments, a particle radiation detection result can be output based on the signal output by the output channel.

[0124] The effects of the present disclosure are described in detail below through simulation examples.

[0125] Continuing to refer to 3, in the simulation example, a pulse signal source pulse and a capacitor C inThis simulates the charge signal generated by particles incident on a particle radiation detector. The pulse signal source, pulse, has an amplitude of 1 mV and a capacitance C. in If the value is 1pF, then the generated charge is 1mV × 1pF = 10. -15 C, which is equivalent to the 22.625 keV of deposited energy produced by the particles incident on the particle radiation detector. R D C is the resistance of the particle radiation detector. D This is the equivalent capacitance of the particle radiation detector. The resistances of channel resistors R2 and R3 are 4.14kΩ and 0.46kΩ respectively. Therefore, the output V of the readout channel (readout channel 2) corresponding to channel resistor R3 is... out2 The amplitude is the output V of the readout channel (readout channel 1) corresponding to the channel resistor R2. out1 One-tenth of the amplitude can expand the energy detection range of the readout channel corresponding to channel resistor R3 by 10 times. n1 and C n2 It's a coupling capacitor. The feedback resistor R... f1 and R f2 The resistance of each capacitor is 1.2 GΩ. The feedback capacitor C... f1 and C f2 The capacitance value is 60fF.

[0126] Reference Figure 6 The diagram shows the relationship between the output voltage amplitude of a particle radiation detector readout circuit and the capacitance of the particle radiation detector. Figure 6 As shown, when the coupling capacitance is kept constant, V out1 and V out2 All of these are related to the capacitance C of the particle radiation detector. D V decreases as it increases. out2 The amplitude is approximately V out1 One-tenth of the capacitance C of different particle radiation detectors D Using the same coupling capacitor will cause a significant change in the output signal of the readout channel.

[0127] Reference Figure 7 The diagram shown illustrates the relationship between the output voltage amplitude and the coupling capacitance of a particle radiation detector readout circuit. Figure 7 As shown, when the capacitance C of the particle radiation detector is maintained... D When V is a constant value, out1 and V out2 All depend on the coupling capacitance C n1 and C n2 V increases with the increase of out2 The amplitude is approximately V out1One-tenth of the value of the coupling capacitor is used to change the amplification factor, thus making the range of the readout channel independent of the amplitude of the input charge signal sent to the preamplifier. However, the value of the coupling capacitor is limited by two factors: the time required for the junction field-effect transistor (JFET) to charge the coupling capacitor and the maximum amplitude of the charge signal sent as input to the charge-sensitive amplifier (CSA).

[0128] Reference Figure 8 The diagram shows the output voltage amplitude of a particle radiation detector readout circuit with a different particle radiation detector capacitor, as shown below. Figure 8 As shown, when the coupling capacitor C is maintained n1 and C n2 When the value of is equal to the capacitance of the particle radiation detector, the capacitance C of different particle radiation detectors... D V out1 There is almost no change, and nearly the same output voltage can be obtained from different particle radiation detectors.

[0129] Reference Figure 9 The diagram shown illustrates the output voltage amplitude of a particle radiation detector readout circuit. Figure 9 As shown, when the coupling capacitor C n1 and C n2 The value is equal to the capacitance C of the particle radiation detector. D When V is the value, out1 This is normal output, while V out2 The amplitude is approximately V out1 One-tenth of that, indicating that the energy detection range of readout channel 2 can be expanded tenfold. V out1 and V out2 Apart from the amplitude, the waveform shape, including rise time, fall time, and half-peak width, is almost identical, which indicates that the present invention can easily change the energy detection range of particle radiation detection.

[0130] For ease of implementation, this specification also provides a particle radiation detection system, see embodiments thereof. Figure 10 The diagram shown illustrates the structure of a particle radiation detection system T, which may include:

[0131] Particle radiation detector D is suitable for detecting particle radiation energy;

[0132] The particle radiation detector readout circuit A is coupled to the particle radiation detector D and is suitable for using the readout circuit described in any of the foregoing embodiments;

[0133] A control module C is coupled to the particle radiation detector readout circuit A and is adapted to control the particle radiation detector readout circuit A to read the output signal of the particle radiation detector through the readout channel matched with the range of the output signal of the particle radiation detector and output a particle radiation detection result based on the output signal of the particle radiation detector.

[0134] With the particle radiation detection system, the particle is injected into the particle radiation detector D, and then the control module C controls the particle radiation detector readout circuit A to read the output signal of the particle radiation detector through the readout channel matched with the range of the output signal of the particle radiation detector based on the energy of the output signal of the particle radiation detector D, and outputs a particle radiation detection result based on the output signal of the particle radiation detector, so that the particle radiation detection with high precision can be realized while the particle radiation detection in different energy ranges and the particle radiation detector with different capacitances are matched.

[0135] In a specific implementation, the particle radiation detector readout circuit A can include a buffer module and a readout module, the buffer module includes a buffer unit and a channel expansion unit, wherein the buffer unit is coupled to the output end of the particle radiation detector and is adapted to read the output signal of the particle radiation detector, and the channel expansion unit includes a plurality of output channels and is adapted to transmit the output signal of the buffer unit from the corresponding output channel to the readout module.

[0136] The buffer unit of the particle radiation detector and the particle radiation detector readout circuit is coupled by a wire.

[0137] With the above embodiment, the buffer unit of the particle radiation detector and the particle radiation detector readout circuit is coupled by a wire, which is simple in structure, easy to implement, and can be flexibly designed according to different particle radiation detection requirements.

[0138] The working process of the particle radiation detection system will be described in detail below through a specific example.

[0139] Referring to Figure 11 A specific structure diagram of a particle radiation detection system is shown, the particle radiation detector D is coupled to the particle radiation detector readout application specific integrated circuit (ASIC) through a junction field effect transistor (JFET). The source output of the source of the JFET is divided into two paths through a channel resistance R2 and a channel resistance R3, one path is output through a coupling capacitor C n1 is coupled to a single channel in the particle radiation detector readout ASIC, and the other path is output through a coupling capacitor C n2The corresponding voltage signal at the source output of the junction field effect transistor (JFET) of another separate channel coupled to the particle radiation detector readout application specific integrated circuit (ASIC) is converted into a charge signal through a coupling capacitor and input to a subsequent amplification and shaping stage (AD) with low impedance. A control module (C) controls the particle radiation detector readout application specific integrated circuit (ASIC) and the amplification and shaping stage (AD) circuit to complete data acquisition using a field programmable gate array (FPGA).

[0140] The effects of the present application are described in detail below by analyzing the collected data.

[0141] Referring to Figure 12 , a schematic diagram of the relationship between the normalized output voltage of a particle radiation detection system and the coupling capacitor, wherein the capacitance C D of the particle radiation detector is a constant value of 51 pF, as shown in Figure 12 , both V out1 and V out2 increase with the increase of the coupling capacitor C n1 and C n2 , the amplitude of V out1 is about one tenth of the amplitude of V out2 , and the amplitude of V out1 and the amplitude of V out2 change proportionally and synchronously.

[0142] Referring to Figure 13 , a schematic diagram of the relationship between the normalized output voltage of a particle radiation detection system and the capacitance of the particle radiation detector, wherein the values of the coupling capacitor C n1 and C n2 are equal to the capacitance C D of the particle radiation detector, as shown in Figure 13 , when the capacitance C D of the particle radiation detector changes, the amplitude of V out1 and the amplitude of V out2 change slightly, V out1 is a normal output, and the amplitude of V out2 is about one tenth of the amplitude of V out1 , indicating that the energy detection range of the readout channel 2 can be expanded by 10 times.

[0143] It can be understood that the present specification does not specifically limit the model of the particle radiation detector readout application specific integrated circuit (ASIC).

[0144] It can be understood that the modules and / or units in the present specification can be composed of discrete devices or implemented by a single chip.

[0145] Although the embodiments of the present specification are disclosed as above, the present application is not limited thereto. Any person skilled in the art, without departing from the spirit and scope of the present application, can make various changes and modifications, and therefore the scope of protection of the present application should be defined by the scope of the claims.

Claims

1. A particle radiation detector readout circuit, characterized by, A readout circuit suitable for coupling with a particle radiation detector, comprising a buffer module and a readout module, wherein: The buffer module comprises a plurality of output channels coupled between the output end of the particle radiation detector and the readout module, and is suitable for transmitting the output signal of the particle radiation detector from the corresponding output channel to the readout module; the buffer module comprises a buffer unit and a channel expansion unit, the buffer unit is coupled with the output end of the particle radiation detector and is suitable for reading the output signal of the particle radiation detector; the buffer unit comprises a junction field effect transistor, the gate of which is coupled with the output end of the particle radiation detector, the drain of which is coupled with a power supply, and the source of which is coupled with the channel expansion unit; a bias resistor is coupled between the power supply and the drain of the junction field effect transistor. The readout module comprises a plurality of readout channels corresponding to the plurality of output channels, and is suitable for outputting particle radiation detection results based on the output signal of the particle radiation detector.

2. The readout circuit of claim 1, wherein: The channel expansion unit comprises a plurality of output channels, and is suitable for transmitting the output signal of the buffer unit from the corresponding output channel to the readout module.

3. The readout circuit according to claim 2, characterized in that The channel expansion unit comprises: A plurality of channel resistors, each channel resistor being connected in series between the source of the junction field effect transistor and the ground; A plurality of output channels, each output channel being arranged between the corresponding channel resistor and the readout channel.

4. The readout circuit according to claim 3, characterized in that The resistance of at least some of the plurality of channel resistors is adjustable.

5. The readout circuit according to claim 4, characterized in that The buffer module further comprises: A coupling capacitor coupled between the corresponding channel resistor and the readout channel.

6. The readout circuit according to claim 5, characterized in that The capacitance of the coupling capacitor is greater than the capacitance of the particle radiation detector.

7. The readout circuit of claim 1, wherein The readout module comprises a readout channel; the readout channel comprises an amplification unit and a feedback unit, wherein: The amplification unit is arranged in the corresponding readout channel and is suitable for amplifying the signal output by the corresponding output channel; The feedback unit is coupled between the output end and the input end of the amplification unit, and is suitable for outputting particle radiation detection results based on the signal output by the output channel.

8. The readout circuit according to claim 7, characterized in that The amplification unit comprises a charge-sensitive amplifier.

9. The readout circuit according to claim 8, characterized in that The feedback unit comprises a feedback resistor and a feedback capacitor, wherein: The feedback resistor is connected in parallel with the charge-sensitive amplifier; The feedback capacitor is connected in parallel with the charge-sensitive amplifier.

10. A particle radiation detection system, characterized by, It comprises: A particle radiation detector suitable for detecting particle radiation energy; A particle radiation detector readout circuit coupled with the particle radiation detector, suitable for using the readout circuit of any one of claims 1-9; A control module coupled with the particle radiation detector readout circuit, suitable for controlling the particle radiation detector readout circuit to read the output signal of the particle radiation detector through the readout channel matched with the range, and outputting particle radiation detection results based on the output signal of the particle radiation detector.

11. The probe system of claim 10, wherein, The particle radiation detector readout circuit comprises a buffer module and a readout module, the buffer module comprises a buffer unit and a channel expansion unit, wherein: the buffer unit is coupled with the output end of the particle radiation detector and is adapted to read out the output signal of the particle radiation detector; the buffer unit comprises a junction field effect transistor, the gate of which is coupled with the output end of the particle radiation detector, the drain of which is coupled with a power supply, and the source of which is coupled with the channel expansion unit; a bias resistor is coupled between the power supply and the drain of the junction field effect transistor; the channel expansion unit comprises a plurality of output channels and is adapted to transmit the output signal of the buffer unit from the corresponding output channel to the readout module. The particle radiation detector and the buffer unit of the particle radiation detector readout circuit are coupled by wires.

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