Beam current integrating device

Abstract

The invention relates to the technical field of beam measurement, and provides a beam integration device, which comprises a logic control module and a plurality of integration modules, each integration module is used for being correspondingly connected with one output channel of a dose distribution detector, and each integration module comprises a current gear selection circuit, an integration circuit and a polarity discrimination circuit, the current gear selection circuit comprises a plurality of current gear channels; the current gear selection circuit is used for selecting a target current gear channel to be connected with an output channel corresponding to the dose distribution detector under the control of the logic control module, and converting a current pulse signal output by the output channel corresponding to the dose distribution detector into a voltage signal; the polarity discrimination circuit discriminates the polarity of the voltage signal and converts the voltage signal into the polarity required by the integrating circuit. According to the beam current integration device, simultaneous integration of multi-channel bipolar current pulse signals is realized, and the integration range is automatically switched according to the change of the current pulse signals.

Description

Technical Field

[0001] The present invention relates to the technical field of beam current measurement, and in particular to a beam current integration device. Background Art

[0002] In high-energy physics experiments, it is necessary to accurately measure the amount of charge when the beam passes through and calculate the ion beam intensity distribution information to provide accurate data support for the experiment. Therefore, a detection device that can detect the beam uniformity and flux distribution in the transmission pipeline is crucial. The beam integrator is one of the important devices for detecting the beam uniformity and flux distribution in the transmission pipeline.

[0003] Most of the existing beam integration devices are implemented based on the IF conversion method (IFC circuit for short), which is a single-channel device. For the multi-channel output of the front-end dose distribution detector, multiple beam integration devices need to be connected; and the beam intensity may change, the size of the current pulse signal output by the dose distribution detector also changes, and the polarity of the current pulse signal may be positive or negative. The existing beam integration devices have a limited measurement range and cannot be remotely controlled to automatically switch the range in a radiation environment. Moreover, a beam integration device is usually only suitable for integrating current pulse signals of one polarity, and cannot adapt to the changes and polarity adaptation of the current pulse signal output by the front-end dose distribution detector. Summary of the invention

[0004] The present invention provides a beam integration device to solve the problem that the beam integration device in the prior art has single-channel integration and cannot adapt to the change and polarity adaptation of the current pulse signal output by the front-end dose distribution detector.

[0005] The present invention provides a beam integration device, comprising: a logic control module and a multi-channel integration module, each of the integration modules is used to correspond to an output channel connected to a dose distribution detector, and each of the integration modules comprises: a current gear selection circuit, a polarity discrimination circuit and an integration circuit; The current range selection circuit includes a plurality of current range channels; the current range selection circuit is used to select a target current range channel to connect with an output channel corresponding to a dose distribution detector under the control of the logic control module, and convert a current pulse signal output by the output channel corresponding to the dose distribution detector into a voltage signal, wherein the value of the current pulse signal output by the output channel corresponding to the dose distribution detector matches the current value range corresponding to the target current range channel; The input end of the polarity discrimination circuit is connected to the output end of the current gear selection circuit, and the output end of the polarity discrimination circuit is connected to the input end of the integration circuit; the polarity discrimination circuit is used to convert the positive polarity voltage signal into a negative polarity voltage signal when the voltage signal output by the current gear selection circuit is positive polarity, and input the negative polarity voltage signal into the integration circuit; The integration circuit is used to convert the negative polarity voltage signal into a current pulse signal, integrate the current pulse signal, and output a square wave signal to the logic control module.

[0006] According to a beam current integration device provided by the present invention, the current range selection circuit further includes: a multiplexer and a first operational amplifier, each of the current range channels includes a first capacitor and a first resistor connected in parallel, and the capacitance values ​​of the first capacitors in different current range channels are different, and the resistance values ​​of the first resistors are different, so as to form different current selection ranges; The input end of the multiplexer serves as the input end of the current range selection circuit, and is used to connect the output channel corresponding to the dose distribution detector and the negative input end of the first operational amplifier. One end of each current range channel is connected to the input end of the multiplexer through the corresponding selection switch in the multiplexer, and the other end of each current range channel is connected to the output end of the first operational amplifier. The positive input end of the first operational amplifier is grounded, and the address control end and the enable end of the multiplexer are connected to the logic control module. The output end of the first operational amplifier serves as the output end of the current range selection circuit. The first operational amplifier and the selected current range channel are used to convert the current pulse signal into the voltage signal, and input the voltage signal from the output end of the first operational amplifier to the polarity discrimination circuit.

[0007] According to a beam integration device provided by the present invention, the logic control module controls the current range selection circuit based on the range selection instruction issued by the host computer, so that the current range selection circuit selects its own input end to be connected to the target current range channel.

[0008] According to a beam current integration device provided by the present invention, each integration module further comprises: a current range identification circuit, the input end of the current range identification circuit is connected to the output end of the current range selection circuit, and the output end of the current range identification circuit is connected to the logic control module; The current range discrimination circuit is used to detect the voltage signal output by the current range selection circuit, and convert the voltage signal into a current signal, and then convert the current signal into a digital signal and send it to the logic control module. The logic control module is used to determine the target current range channel according to the digital signal, and control the current range selection circuit to select its own input end to be connected to the target current range channel.

[0009] According to a beam integration device provided by the present invention, the polarity discrimination circuit comprises: a two-to-one selector, a second operational amplifier, a third operational amplifier, a second resistor, a third resistor, a fourth resistor and a fifth resistor, wherein the second operational amplifier and the third operational amplifier are both inverting amplifiers; Two ends of the third resistor are respectively connected to the negative input terminal and the output terminal of the second operational amplifier; two ends of the fifth resistor are respectively connected to the negative input terminal and the output terminal of the third operational amplifier; The input end of the two-to-one selector is used as the input end of the polarity discrimination circuit and is connected to the output end of the current range selection circuit. The first output end of the two-to-one selector is connected to the negative input end of the second operational amplifier through the second resistor. The second output end of the two-to-one selector is connected to the output end of the second operational amplifier and is connected to the negative input end of the third operational amplifier through the fourth resistor. The polarity selection control end of the two-to-one selector is connected to the logic control module. The positive input terminals of the second operational amplifier and the third operational amplifier are grounded, and the output terminal of the third operational amplifier is connected to the input terminal of the integration circuit as the output terminal of the polarity discrimination circuit; The logic control module is used to control the input end and the second output end of the two-to-one selector to be connected when the voltage signal output by the current range selection circuit is positive polarity, and to control the input end and the first output end of the two-to-one selector to be connected when the voltage signal output by the current range selection circuit is negative polarity.

[0010] According to a beam current integration device provided by the present invention, each integration module further comprises: a current range discrimination circuit, the input end of the current range discrimination circuit is connected to the output end of the polarity discrimination circuit, and the output end of the current range discrimination circuit is connected to the logic control module; The current range discrimination circuit is used to detect the negative polarity voltage signal output by the polarity discrimination circuit, and convert the negative polarity voltage signal into a current signal, and then convert the current signal into a digital signal and send it to the logic control module. The logic control module is used to determine the target current range channel according to the digital signal, and control the current range selection circuit to select its own input end to be connected to the target current range channel.

[0011] According to a beam current integration device provided by the present invention, the current range discrimination circuit comprises: a comparator, a current sensing monitor, an analog-to-digital converter, a first triode, a first diode, a second capacitor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor and a twelfth resistor; One end of the sixth resistor is connected to the output end of the polarity discrimination circuit as the input end of the current range discrimination circuit, and the other end of the sixth resistor is connected to the positive input end of the comparator; The negative input terminal of the comparator is grounded, the output terminal of the comparator is connected to the base of the first transistor, the two ends of the second capacitor are respectively connected to the positive input terminal of the comparator and the output terminal of the comparator, and the two ends of the seventh resistor are respectively connected to the positive input terminal of the comparator and the output terminal of the comparator; One end of the eighth resistor is connected to the positive power supply terminal, and the other end is connected to the base of the first transistor; One end of the ninth resistor is connected to the negative power supply end, and the other end is connected to the base of the first transistor; The anode of the first diode is connected to the base of the first transistor, and the cathode is connected to the emitter of the first transistor; The collector of the first transistor is connected to one end of the tenth resistor, the other end of the tenth resistor is connected in series with the eleventh resistor and then grounded, and the other end of the tenth resistor is connected to the output end of the polarity discrimination circuit; The two input ends of the current sensing monitor are respectively connected to the two ends of the eleventh resistor, and the output end of the current sensing monitor is connected to the input end of the analog-to-digital converter; The output end of the analog-to-digital converter is connected to the logic control module as the output end of the current range discrimination circuit.

[0012] According to a beam integration device provided by the present invention, each of the integration modules further includes: a driving circuit for stabilizing the square wave signal and inputting the stabilized square wave signal to a logic control module.

[0013] According to a beam integration device provided by the present invention, the driving circuit includes: an AND gate, a second transistor, a second diode, a thirteenth resistor and a fourteenth resistor, the first input end of the AND gate is connected to the positive power supply end through the thirteenth resistor, the second input end of the AND gate is connected to the output end of the integration circuit, the output end of the AND gate is connected to the base of the second transistor, the collector of the second transistor is connected to the positive power supply end, the emitter is connected to the first end of the fourteenth resistor, the second end of the fourteenth resistor is grounded, the anode of the second diode is connected to the emitter of the second transistor, the cathode is connected to the base of the second transistor, and the first end of the fourteenth resistor is the output end of the driving circuit connected to the logic control module.

[0014] A beam integration device provided according to the present invention further includes: a mother circuit board and at least one sub-circuit board, the logic control module is arranged on the mother circuit board, the integration module is arranged on the sub-circuit board, and the sub-circuit board is detachably connected to the mother circuit board.

[0015] The beam integration device provided by the present invention realizes multi-channel simultaneous integration because it includes multiple integration modules; each integration module includes a current range selection circuit, and the current range selection circuit includes multiple current range channels. Since the front-end dose distribution detector outputs current pulse signals with different ranges, the logic control module selects the current range channel that matches the value of the current pulse signal as the target current range channel according to the change of the current pulse signal, and controls the current range selection circuit to select the target current range channel to connect with the output channel corresponding to the dose distribution detector, thereby realizing automatic switching of the integration range, and can convert current pulse signals with different ranges into voltage signals of uniform size for processing, so as to meet the wide range input; and the polarity discrimination circuit can perform polarity conversion on the bipolar voltage signal output by the current range selection circuit, and generate a negative polarity voltage signal suitable for the back-end integration circuit, thereby realizing the input function of the bipolar current pulse signal of the front-end current range selection circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the module structure of the beam integration device provided by the present invention.

[0018] Figure 2It is a schematic diagram of the circuit structure of the beam integration device provided by the present invention.

[0019] Figure 3 It is a schematic diagram of the structure of the current gear selection circuit in the beam integration device provided by the present invention.

[0020] Figure 4 It is a schematic diagram of the structure of the integration circuit in the beam integration device provided by the present invention.

[0021] Figure 5 It is a schematic diagram of the structure of the polarity discrimination circuit in the beam integration device provided by the present invention.

[0022] Figure 6 It is a schematic diagram of the structure of the current range discrimination circuit in the beam current integration device provided by the present invention.

[0023] Figure 7 It is a schematic diagram of the structure of the driving circuit in the beam integration device provided by the present invention.

[0024] Figure 8 It is a schematic diagram of the circuit layout structure of the beam integration device provided by the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The beam integration device of the embodiment of the present invention is as follows Figure 1 and Figure 2 As shown, it includes: a logic control module 100 and a multi-channel integration module, each of the integration modules is used to correspond to an output channel connected to the dose distribution detector, that is, during the experiment, each integration module corresponds to an output channel connected to the front-end dose distribution detector, so as to integrate the current pulse signal output by the output channel, thereby realizing the simultaneous integration of the current pulse signals output by multiple channels of the dose distribution detector.

[0027] In this embodiment, each integration module includes: a current range selection circuit 200 , an integration circuit 300 and a polarity discrimination circuit 500 .

[0028] The current range selection circuit 200 includes multiple current range channels. The current range selection circuit 200 is used to select a target current range channel to connect with the output channel corresponding to the dose distribution detector under the control of the logic control module 100, and convert the current pulse signal output by the output channel corresponding to the dose distribution detector into a voltage signal. The value of the current pulse signal output by the output channel corresponding to the dose distribution detector matches the current value range corresponding to the target current range channel.

[0029] The input end of the polarity discrimination circuit 500 is connected to the output end of the current range selection circuit 200, and the output end of the polarity discrimination circuit 500 is connected to the input end of the integration circuit 300. The polarity discrimination circuit 500 is used to convert the positive polarity voltage signal into a negative polarity voltage signal when the voltage signal output by the current range selection circuit 200 is positive polarity, and input the negative polarity voltage signal to the integration circuit 300. In this embodiment, the bipolar voltage signal is polarity-converted by the polarity discrimination circuit 500 to generate a negative polarity voltage signal suitable for the back-end integration circuit 300, thereby realizing the input function of the bipolar current pulse signal of the front-end current range selection circuit 200.

[0030] The integration circuit 300 is used to convert the negative voltage signal into a current pulse signal, integrate the current pulse signal, and output a square wave signal to the logic control module 100, so that the logic control module 100 accumulates the square wave signal counts to obtain the total charge. In this embodiment, the logic control module 100 can use an Artix 7 series FPGA chip, the chip model is XC7A200TFBG484-2L, and its FPGA logic unit is 215K in total and the storage unit is 13.1Mbit.

[0031] Specifically, when the size of the current pulse signal output by the output channel corresponding to the front-end dose distribution detector changes, the logic control module 100 selects the current range channel that matches the value of the current pulse signal as the target current range channel according to the value of the current pulse signal currently output by the output channel corresponding to the dose distribution detector, and controls the current range selection circuit 200 to select the target current range channel to be connected to the output channel corresponding to the dose distribution detector, thereby realizing automatic switching of the current range channel according to the change of the current pulse signal, that is, automatic switching of the integration range, so that the integration circuit 300 can integrate the changed current pulse signal.

[0032] The beam integration device of this embodiment, because it includes multiple integration modules, realizes multi-channel integration at the same time, and each integration module includes a current gear selection circuit 200, and the current gear selection circuit 200 includes multiple current gear channels. Since the front-end dose distribution detector outputs current pulse signals of different gears, the logic control module 100 selects the current gear channel that matches the value of the current pulse signal as the target current gear channel according to the change of the current pulse signal, and controls the current gear selection circuit 200 to select the target current gear channel and connect it to the output channel corresponding to the dose distribution detector, thereby realizing the automatic switching of the integration range, and can convert different gear current pulse signals into uniform voltage signals for processing, so as to meet the wide range input. Moreover, the polarity discrimination circuit 500 can convert the polarity of the bipolar voltage signal output by the current gear selection circuit 200, and generate a negative voltage signal suitable for the back-end integration circuit 300, thereby realizing the input function of the bipolar current pulse signal of the front-end current gear selection circuit 200.

[0033] like Figure 2 and Figure 3 As shown, in some embodiments, the current range selection circuit 200 further includes: a multiplexer 201 and a first operational amplifier OP1, each of the current range channels includes a first capacitor and a first resistor connected in parallel, Figure 3 8 sets of current range channels are shown, including first capacitors C1.1-C1.8 and first resistors R1.1-R1.8. The capacitance values ​​of the first capacitors in different current range channels are different, and the resistance values ​​of the first resistors are different, so as to form different current selection ranges. For example: Figure 3 In the figure, eight different current range channels are formed, each of which is a parallel circuit formed by a corresponding first capacitor and a first resistor, wherein the 0.01nA range indicates that a current pulse signal with a current value not exceeding 0.01nA is connected to a subsequent polarity discrimination circuit 500 through the 0.01nA range channel, and a current pulse signal with a current value exceeding 10uA but not exceeding 100uA is connected to a subsequent polarity discrimination circuit 500 through the 100uA range channel.

[0034] The input end of the multiplexer 201 is used as the input end of the current range selection circuit 200, and is used to connect the output channel corresponding to the dose distribution detector, and is connected to the negative input end of the first operational amplifier OP1. One end of each current range channel is connected to the input end of the multiplexer 201 through the corresponding selection switch in the multiplexer 201, and the other end of each current range channel is connected to the output end of the first operational amplifier OP1. The positive input end of the first operational amplifier OP1 is grounded, and the address control end and the enable end EN of the multiplexer 201 are connected to the logic control module 100. The output end of the first operational amplifier OP1 is used as the output end of the current range selection circuit 200. The first operational amplifier OP1 and the selected current range channel are used to convert the current pulse signal into a voltage signal, and the voltage signal is input from the output end of the first operational amplifier OP1 to the polarity discrimination circuit 500. Among them, when the selection switch corresponding to any current range channel is closed, the any current range channel and the first operational amplifier OP1 form a transimpedance amplifier circuit to amplify and convert the current pulse signal output by the output channel corresponding to the dose distribution detector.

[0035] In this embodiment, Figure 3 As shown, since eight current range channels are provided, the multiplexer 201 can select a multiplexer with one input and eight outputs (S1-S8), wherein there are eight selection switches (i.e., decoding switches) SW1-SW8. Since there are eight outputs, the address control end of the multiplexer 201 has three pins. The three-bit binary signal output by the logic control module 100 determines which output end of the multiplexer 201 is connected to the input end of the multiplexer 201, that is, which current range channel is connected to the corresponding output channel of the front-end dose distribution detector, so that the current range channel cooperates with the first operational amplifier OP1 to output a voltage signal.

[0036] The current range selection circuit 200 of this embodiment uses a circuit structure composed of a multiplexer 201, a first operational amplifier OP1 and multiple current range channels to achieve output voltage signals of equal magnitude after different current pulse signals pass through transimpedance amplifier circuits corresponding to different ranges to meet the needs of subsequent integration circuits.

[0037] Specifically, the multiplexer 201 can select the TMUX8108RUMR device, which supports high power supply voltage (dual power supply ±10V~±50V), provides consistent analog parameter performance in the entire power supply voltage range, has latch suppression function, can be used in harsh environments, and has low crosstalk, low input leakage current (40pA) and low on-resistance flatness (0.5Ω). In this embodiment, different amplification factors are determined by adjusting the feedback resistance and capacitance in the transimpedance amplifier circuit, so as to achieve the function of adjusting the gear. The smaller the input current, the larger the feedback resistance of the corresponding gear, so as to ensure that the output voltage signal after passing through the transimpedance amplifier circuit corresponding to different gears is the same. The first operational amplifier OP1 can select the CA3140 device, which combines the advantages of high-voltage PMOS transistors and high-voltage bipolar transistors on a single chip. Insulated gate field effect transistors (MOSFETs) are used in the input circuit to provide very high input impedance (1.5TΩ), very low input current (10pA@±15V) and high-speed performance. The CA3140 device also supports high power supply voltage (dual power supply ±18V).

[0038] It should be noted that the integration circuit 300 can be composed of three parts: a feedback current integrator, an amplitude discriminator, and a pulse current source. Figure 2 The current pulse signal of the fifteenth resistor R15 is first converted into a sawtooth voltage signal through a feedback current integrator, and then converted into a square wave signal output through an amplitude discriminator under the action of a pulse current source.

[0039] The feedback current integrator is used to convert the current pulse signal into a sawtooth voltage signal, including: a fourth operational amplifier OP4, a third transistor M3, an integrating capacitor C3 and a fifteenth resistor R15, the third transistor M3 is an NPN transistor; the amplitude discriminator includes: a common-direction hysteresis comparator COM2, a nineteenth resistor R19 and a twentieth resistor R20; the pulse current source includes: a fourth transistor M4, a third diode D3, a sixteenth resistor R16, a seventeenth resistor R17 and an eighteenth resistor R18, the fourth transistor M4 is a PNP transistor. The connection structures of the feedback current integrator, the amplitude discriminator and the pulse current source and the connection structures among the three are shown in FIG. Figure 4 shown.

[0040] When the third transistor M3 is in saturation state, the voltage V between its collector and emitter can be ignored. ce , mainly considering the base voltage V be , about 1V. In this state, the third transistor M3 is used as a switch to effectively control the on and off of the circuit. Since the fourth operational amplifier OP4 has a large input impedance (R i ≥10 12Ω), the input current will all pass through the integrating capacitor C3, so the output voltage U of the feedback current integrator Q Increases linearly over time, that is: U Q = (I×t) / c, where I represents the magnitude of the current pulse signal passing through the fifteenth resistor R15, t represents the integration time, and c represents the capacitance value of the capacitor C3.

[0041] The output of the amplitude discriminator does not immediately follow the input signal when its input signal changes, but changes only after the input signal reaches a certain threshold. The main advantage of this amplitude discriminator is that it can effectively suppress false triggering caused by noise or fluctuations in the input signal. Under the positive feedback mechanism, its output can be maintained stably after the input signal crosses the threshold point, thereby improving the stability and reliability of the system.

[0042] When the input voltage V i Less than the lower threshold V L When the output voltage of the amplitude discriminator is o Flip to low level U L , when V i Increases above the upper threshold V H When V o Flip to high level U H . Figure 4 Medium V TH is the reference voltage of the amplitude discriminator. The upper and lower thresholds of the amplitude discriminator can be calculated by the following formulas: V H =r 19 ×V TH / r 20 + V TH ; V L = (V TH ×(r 19 +r 20 )-U H × 19 ) / r 20 .

[0043] Among them, r 19 and r 20 They respectively represent the resistance values ​​of the nineteenth resistor R19 and the twentieth resistor R20.

[0044] The pulse current source is a pulse current circuit composed of a PNP transistor voltage divider bias circuit powered by a positive polarity power supply. The fourth transistor M4 in the circuit is a PNP transistor, Vcc is a positive polarity DC working voltage, the sixteenth resistor R16 and the seventeenth resistor R17 form a voltage divider bias circuit, and the eighteenth resistor R18 is the emitter resistor of the fourth transistor M4. The main function of the bias circuit of the fourth transistor M4 powered by a positive polarity power supply is to ensure the normal operation of the transistor, optimize the amplification effect and realize different circuit functions. The emitter of the fourth transistor M4 is connected to the positive polarity DC working voltage Vcc terminal through the eighteenth resistor R18. The emitter DC voltage of the fourth transistor M4 is the highest, which is higher than the base DC voltage of the fourth transistor M4. Therefore, the emitter junction of the fourth transistor M4 (the PN junction between the base and the emitter) is in a forward biased state, which meets one of the necessary conditions for the fourth transistor M4 to work in the amplification state. Figure 4 As shown, the DC current flowing out of the DC power supply Vcc is I, the current flowing through the sixteenth resistor R16 is i1, the current flowing through the seventeenth resistor R17 is i2, and the current flowing out of the base of the fourth transistor M4 is i B (Because the fourth transistor M4 is a PNP transistor, its base current flows out from the tube), i2= i1+i B , the seventeenth resistor R17 forms a base current loop. Since the fourth transistor M4 is in the amplification state, referring to the device manual of the fourth transistor M4, it can be known that the amplification factor β of the transistor is about 96~246 times, so i C ≈96×i B .

[0045] The structure and integration principle of the integration circuit 300 are substantially the same as those of the existing feedback current integration circuit, and will not be described in detail herein.

[0046] In some embodiments, the logic control module 100 controls the current range selection circuit 200 based on the range selection instruction sent by the host computer, so that the current range selection circuit 200 selects its own input terminal to be connected to the target current range channel.

[0047] Specifically, when the magnitude of the current pulse signal output by each channel of the front-end dose distribution detector is known, the user can set the corresponding gear selection instruction on the host computer, and the host computer sends the gear selection instruction to the logic control module 100, and the logic control module 100 generates a corresponding binary address control signal according to the gear selection instruction, and sends the address control signal to the address control end of the multiplexer 201. For example: the gear selection instruction can be directly the current value of the current pulse signal output by each channel of the front-end dose distribution detector or carry the current value, and the logic control module 100 determines which current gear channel should be selected according to the current value.

[0048] It is understandable that the logic control module 100 pre-stores the current value threshold range corresponding to each current range channel, so that the logic control module 100 automatically selects the target current range channel according to the current value in the range selection instruction.

[0049] In some embodiments, each integration module further includes: a current range identification circuit 600 , the input end of the current range identification circuit 600 is connected to the output end of the current range selection circuit 200 , and the output end of the current range identification circuit 600 is connected to the logic control module 100 .

[0050] The current range discrimination circuit 600 is used to detect the voltage signal output by the current range selection circuit 200, and convert the voltage signal into a current signal, and then convert the current signal into a digital signal and send it to the logic control module 100. The logic control module 100 is used to determine the target current range channel according to the digital signal, that is, to select the current range corresponding to the current pulse signal output from the output end corresponding to the dose distribution detector, and control the current range selection circuit 200 to select its own input end to be connected to the target current range channel.

[0051] In this embodiment, the voltage signal currently output by the current range discrimination circuit 600 is identified by the current range discrimination circuit 600, and finally converted into a corresponding digital signal and given to the logic control module 100. The logic control module 100 determines the target current range channel according to the digital signal, thereby realizing the function of automatically identifying the voltage signal output by the current range selection circuit 200 and automatically selecting the target current range channel.

[0052] It is understandable that the logic control module 100 pre-stores the digital threshold range of the digital signal corresponding to each current range channel, so that the logic control module 100 automatically selects the target current range channel according to the digital signal output by the current range discrimination circuit 600 .

[0053] like Figure 2 and Figure 5 As shown, in some embodiments, the polarity discrimination circuit 500 includes: a two-to-one selector 501, a second operational amplifier OP2, a third operational amplifier OP3, a second resistor R2, a third resistor R3, a fourth resistor R4 and a fifth resistor R5, and the second operational amplifier OP2 and the third operational amplifier OP3 are both reverse amplifiers.

[0054] The two ends of the third resistor R3 are respectively connected to the negative input terminal and the output terminal of the second operational amplifier OP2; the two ends of the fifth resistor R5 are respectively connected to the negative input terminal and the output terminal of the third operational amplifier OP3. Specifically, the second resistor R2 is equal to the third resistor R3, the second operational amplifier OP2 only realizes polarity conversion, the fourth resistor R4 and the fifth resistor R5 are in a multiple relationship, the fifth resistor R5 is 5.5 times the fourth resistor R4, and the third operational amplifier OP3 not only realizes polarity conversion but also realizes amplification function.

[0055] The input end of the two-select-one selector 501 is used as the input end of the polarity discrimination circuit 500, connected to the output end of the current range selection circuit 200, specifically, connected to the output end of the first operational amplifier OP1. The first output end of the two-select-one selector 501 is connected to the negative input end of the second operational amplifier OP2 through the second resistor R2, the second output end of the two-select-one selector 501 is connected to the output end of the second operational amplifier OP2, and connected to the negative input end of the third operational amplifier OP3 through the fourth resistor R4, and the polarity selection control end of the two-select-one selector 501 is connected to the logic control module 100.

[0056] The positive input terminals of the second operational amplifier OP2 and the third operational amplifier OP3 are grounded. The output terminal of the third operational amplifier OP3 is connected to the input terminal of the integration circuit 300 as the output terminal of the polarity discrimination circuit 500 .

[0057] The logic control module 100 is used to control the input end and the second output end of the two-to-one selector 501 to be connected when the voltage signal output by the current gear selection circuit 200 is positive, that is, through the fourth resistor R4 and the third operational amplifier OP3, the positive voltage signal is reversed and amplified into a negative voltage signal, and output to the subsequent integration circuit 300. When the voltage signal output by the current gear selection circuit 200 is negative, the input end and the first output end of the two-to-one selector 501 are controlled to be connected, that is, through the second resistor R2 and the second operational amplifier OP2, the negative voltage signal is reversed into a positive voltage signal, and then through the fourth resistor R4 and the third operational amplifier OP3, the positive voltage signal is reversed and amplified into a negative voltage signal, and output to the subsequent integration circuit 300.

[0058] In this embodiment, the specific circuit structure of the polarity discrimination circuit 500 is simple. No matter whether the input voltage signal is a positive polarity or a negative polarity voltage signal, it can be converted and amplified into a negative polarity voltage signal to meet the requirements of the subsequent integration circuit 300.

[0059] It can be understood that: when conducting beam-related physical experiments, the polarity of the current pulse signal output by each output channel of the front-end dose distribution detector is determined, and the polarity of the current pulse signal can be set in the host computer, and the set polarity is sent to the logic control module 100. The logic control module 100 outputs a polarity selection control signal according to the set polarity to control the two-to-one selector 501 to select the corresponding output end, so that the entire beam integration device is suitable for outputting dose distribution detectors with different polarities.

[0060] In some embodiments, each integration module further includes: a current range identification circuit 600, the input end of the current range identification circuit 600 is connected to the output end of the polarity identification circuit 500, specifically connected to the output end of the third operational amplifier OP3, and the output end of the current range identification circuit 600 is connected to the logic control module 100.

[0061] The current range discrimination circuit 600 is used to detect the negative polarity voltage signal output by the polarity discrimination circuit 500, and convert the negative polarity voltage signal into a current signal, and then convert the current signal into a digital signal and send it to the logic control module 100. The logic control module 100 is used to determine the target current range channel according to the digital signal, that is, to select the current range corresponding to the current pulse signal output from the output end corresponding to the dose distribution detector, and control the current range selection circuit 200 to select its own input end to be connected to the target current range channel.

[0062] In this embodiment, the polarity discrimination circuit 500 always outputs a negative polarity voltage signal. The current range discrimination circuit 600 is arranged after the output of the polarity discrimination circuit 500. Only the corresponding discrimination circuit structure is designed for the negative polarity voltage signal, and there is no need to design a discrimination circuit structure for the positive polarity voltage signal. That is, there is no need for two structures of current range discrimination circuits, which makes the circuit structure of the current range discrimination circuit 600 simpler.

[0063] In some embodiments, Figure 2 and Figure 6 As shown, the current range discrimination circuit 600 includes: a comparator COM1, a current sensing monitor 601, an analog-to-digital converter 602 (ADC), a first transistor M1, a first diode D1, a second capacitor C2, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11 and a twelfth resistor R12. In this embodiment, the first transistor M1 is a PNP transistor.

[0064] One end of the sixth resistor R6 is connected to the output end of the polarity identification circuit 500 as the input end of the current range identification circuit 600, specifically connected to the output end of the third operational amplifier OP3 in the polarity identification circuit 500, and the other end of the sixth resistor R6 is connected to the positive input end of the comparator COM1.

[0065] The negative input terminal of the comparator COM1 is grounded, the output terminal of the comparator COM1 is connected to the base of the first transistor M1, the two ends of the second capacitor C2 are respectively connected to the positive input terminal of the comparator COM1 and the output terminal of the comparator COM1, and the two ends of the seventh resistor R7 are respectively connected to the positive input terminal of the comparator COM1 and the output terminal of the comparator COM1.

[0066] One end of the eighth resistor R8 is connected to the positive power supply terminal +Vcc, and the other end is connected to the base of the first transistor M1. The eighth resistor R8 is a pull-up resistor, which is used to pull up the base voltage of the first transistor M1 so that when it is in the cut-off state, the switch is in the off state.

[0067] One end of the ninth resistor R9 is connected to the negative power supply terminal -Vcc, and the other end is connected to the base of the first transistor M1. The ninth resistor R9 is a pull-down resistor, which is used to connect the base of the first transistor M1 to a low level, and can stabilize the signal to prevent unnecessary interference and false triggering.

[0068] The anode of the first diode D1 is connected to the base of the first transistor M1 , and the cathode of the first diode D1 is connected to the emitter of the first transistor M1 .

[0069] The collector of the first transistor M1 is connected to one end of the tenth resistor R10 , the other end of the tenth resistor R10 is connected in series with the eleventh resistor R11 and then grounded, and the other end of the tenth resistor R10 is connected to the output end of the polarity identification circuit 500 .

[0070] Two input terminals of the current sensing monitor 601 are respectively connected to two terminals of the eleventh resistor R11 , and an output terminal of the current sensing monitor 601 is connected to an input terminal of the analog-to-digital converter 602 for sending the sensed current signal (analog signal) to the analog-to-digital converter 602 .

[0071] The output end of the analog-to-digital converter 602 is connected to the logic control module 100 as the output end of the current range discrimination circuit 600 , and is used to convert the current signal sensed by the current sensing monitor 601 into a digital signal and send it to the logic control module 100 .

[0072] Specifically, the negative voltage signal V output by the polarity discrimination circuit 500 is IThe current is first compared with the zero level by the comparator COM1, and the output low-level signal controls the first transistor M1 to conduct, allowing current to flow from the emitter to the collector, and then forms a voltage drop across the eleventh resistor R11, so that the current sensing monitor 601 obtains the current signal, and converts it into a digital signal through the analog-to-digital converter 602 and transmits it to the logic control module 100 for processing, so that the logic control module 100 can determine the current range channel.

[0073] It should be noted that: the voltage across the eleventh resistor R11 is different from the negative voltage signal output by the polarity discrimination circuit 500 , but they are of the same order of magnitude and will not affect the selection of the current range channel.

[0074] In some embodiments, each integration module further includes: a driving circuit 400, which is used to stabilize the square wave signal and input the stable square wave signal to the logic control module 100, so that the logic control module 100 can count the square wave signal more accurately.

[0075] In some embodiments, Figure 7 As shown, the driving circuit 400 includes: an AND gate 401, a second triode M2, a second diode D2, a thirteenth resistor R13 and a fourteenth resistor R14. In this embodiment, the second triode M2 ​​is an NPN type triode. The first input end of the AND gate 401 is connected to the positive power supply end +Vcc through the thirteenth resistor R13, and the second input end of the AND gate 401 is connected to the output end of the integration circuit 300, specifically connected to the output end of the amplitude discriminator in the integration circuit 300, and receives the square wave signal output by the amplitude discriminator. The output end of the AND gate 401 is connected to the base of the second triode M2, the collector of the second triode M2 ​​is connected to the positive power supply end +Vcc, the emitter is connected to the first end of the fourteenth resistor R14, the second end of the fourteenth resistor R14 is grounded, the anode of the second diode D2 is connected to the emitter of the second triode M2, the cathode is connected to the base of the second triode M2, and the first end of the fourteenth resistor R14 is the output end of the driving circuit 400 connected to the logic control module 100.

[0076] In this embodiment, the square wave signal output by the amplitude discriminator is received through the second input terminal of the AND gate 401, and the first input terminal is connected to the positive power supply terminal +Vcc. When the square wave is at a high level, a high level (logic 1) is output, and when the square wave is at a low level, a low level (logic 0) is output, and the output frequency is consistent with the square wave frequency. The circuit after the output terminal of the AND gate 401 forms a voltage follower circuit. Since the square wave signal output by the amplitude discriminator in the integration circuit 300 is divided into two paths, one path is output to the pulse current source in the integration circuit 300, and the other path is output to the logic control module 100, the square wave signal is divided, which will affect its amplitude. In order to ensure that the amplitude of the square wave input to the logic control module 100 meets the standard CMOS level required by the logic control module 100, a fourteenth resistor R14 with a suitable resistance value is set in the voltage follower circuit to ensure that the amplitude of the square wave finally input to the logic control module 100 is the standard CMOS level.

[0077] The voltage follower circuit has the advantages of high input impedance, low output impedance, signal buffering and preventing signal distortion. Among them, a second diode D2 is connected between the emitter and the base of the second triode M2 ​​to protect the emitter from the influence of reverse voltage and prevent the emitter junction from breaking down, while providing a current cutoff function to control the conduction and cutoff of the second triode M2. The fourteenth resistor R14 is used to generate current negative feedback, which can stabilize the static operating point, drive the back-end load circuit, and improve the reliability of the system.

[0078] In some embodiments, the beam integration device further includes: a mother circuit board and at least one sub-circuit board, the logic control module is arranged on the mother circuit board, the integration module is arranged on the sub-circuit board, and the sub-circuit board is detachably connected to the mother circuit board.

[0079] Specifically, each sub-circuit board can be provided with a multi-channel integration module, such as Figure 8 In the embodiment, four sub-circuits are included, and three integration modules are arranged on each sub-circuit board. In this embodiment, a mother-subcircuit board structure is adopted, and the logic control module is arranged on the mother circuit board, and the integration module is arranged on the sub-circuit board, which is convenient for the replacement and maintenance of the circuit, as well as the subsequent expandable design. In particular, the integration modules are distributed on different sub-circuit boards. If one of the integration modules is damaged, only the corresponding sub-circuit board needs to be replaced, which reduces the cost of maintenance and replacement.

[0080] In this embodiment, the logic control module can be connected to the host computer via a USB interface or an Ethernet interface, receive relevant control instructions issued by the host computer, and send the integration result to the host computer, and can also display the integration result on a liquid crystal display.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A beam integration device, characterized in that: include: A logic control module and a multi-channel integration module, each of which is used to correspond to an output channel connected to a dose distribution detector, and each of which includes: a current gear selection circuit, a polarity discrimination circuit and an integration circuit; The current range selection circuit includes a plurality of current range channels; the current range selection circuit is used to select a target current range channel to connect with an output channel corresponding to a dose distribution detector under the control of the logic control module, and convert a current pulse signal output by the output channel corresponding to the dose distribution detector into a voltage signal, wherein the value of the current pulse signal output by the output channel corresponding to the dose distribution detector matches the current value range corresponding to the target current range channel; The input end of the polarity discrimination circuit is connected to the output end of the current gear selection circuit, and the output end of the polarity discrimination circuit is connected to the input end of the integration circuit; the polarity discrimination circuit is used to convert the positive polarity voltage signal into a negative polarity voltage signal when the voltage signal output by the current gear selection circuit is positive polarity, and input the negative polarity voltage signal into the integration circuit; The integration circuit is used to convert the negative polarity voltage signal into a current pulse signal, integrate the current pulse signal, and output a square wave signal to the logic control module.

2. The beam integrator according to claim 1, characterized in that: The current range selection circuit further includes: a multiplexer and a first operational amplifier, each of the current range channels includes a first capacitor and a first resistor connected in parallel, the capacitance values ​​of the first capacitors in different current range channels are different, and the resistance values ​​of the first resistors are different, so as to form different current selection ranges; The input end of the multiplexer serves as the input end of the current range selection circuit, and is used to connect the output channel corresponding to the dose distribution detector and the negative input end of the first operational amplifier. One end of each current range channel is connected to the input end of the multiplexer through the corresponding selection switch in the multiplexer, and the other end of each current range channel is connected to the output end of the first operational amplifier. The positive input end of the first operational amplifier is grounded, and the address control end and the enable end of the multiplexer are connected to the logic control module. The output end of the first operational amplifier serves as the output end of the current range selection circuit. The first operational amplifier and the selected current range channel are used to convert the current pulse signal into the voltage signal, and input the voltage signal from the output end of the first operational amplifier to the polarity discrimination circuit.

3. The beam integrator according to claim 1, characterized in that: The logic control module controls the current range selection circuit based on the range selection instruction sent by the host computer, so that the current range selection circuit selects its own input end to be connected to the target current range channel.

4. The beam integrator according to claim 1, characterized in that: Each of the integration modules further comprises: a current range identification circuit, wherein the input end of the current range identification circuit is connected to the output end of the current gear selection circuit, and the output end of the current range identification circuit is connected to the logic control module; The current range discrimination circuit is used to detect the voltage signal output by the current range selection circuit, and convert the voltage signal into a current signal, and then convert the current signal into a digital signal and send it to the logic control module. The logic control module is used to determine the target current range channel according to the digital signal, and control the current range selection circuit to select its own input end to be connected to the target current range channel.

5. The beam integrator according to claim 1, characterized in that: The polarity discrimination circuit comprises: a two-to-one selector, a second operational amplifier, a third operational amplifier, a second resistor, a third resistor, a fourth resistor and a fifth resistor, wherein the second operational amplifier and the third operational amplifier are both reverse amplifiers; Two ends of the third resistor are respectively connected to the negative input terminal and the output terminal of the second operational amplifier; two ends of the fifth resistor are respectively connected to the negative input terminal and the output terminal of the third operational amplifier; The input end of the two-to-one selector is used as the input end of the polarity discrimination circuit and is connected to the output end of the current range selection circuit. The first output end of the two-to-one selector is connected to the negative input end of the second operational amplifier through the second resistor. The second output end of the two-to-one selector is connected to the output end of the second operational amplifier and is connected to the negative input end of the third operational amplifier through the fourth resistor. The polarity selection control end of the two-to-one selector is connected to the logic control module. The positive input terminals of the second operational amplifier and the third operational amplifier are grounded, and the output terminal of the third operational amplifier is connected to the input terminal of the integration circuit as the output terminal of the polarity discrimination circuit; The logic control module is used to control the input end and the second output end of the two-to-one selector to be connected when the voltage signal output by the current range selection circuit is positive polarity, and to control the input end and the first output end of the two-to-one selector to be connected when the voltage signal output by the current range selection circuit is negative polarity.

6. The beam integrator according to claim 1, characterized in that: Each of the integration modules further comprises: a current range discrimination circuit, the input end of the current range discrimination circuit is connected to the output end of the polarity discrimination circuit, and the output end of the current range discrimination circuit is connected to the logic control module; The current range discrimination circuit is used to detect the negative polarity voltage signal output by the polarity discrimination circuit, and convert the negative polarity voltage signal into a current signal, and then convert the current signal into a digital signal and send it to the logic control module. The logic control module is used to determine the target current range channel according to the digital signal, and control the current range selection circuit to select its own input end to be connected to the target current range channel.

7. The beam integrator according to claim 6, characterized in that: The current range identification circuit includes: a comparator, a current sensing monitor, an analog-to-digital converter, a first transistor, a first diode, a second capacitor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor and a twelfth resistor; One end of the sixth resistor is connected to the output end of the polarity discrimination circuit as the input end of the current range discrimination circuit, and the other end of the sixth resistor is connected to the positive input end of the comparator; The negative input terminal of the comparator is grounded, the output terminal of the comparator is connected to the base of the first transistor, the two ends of the second capacitor are respectively connected to the positive input terminal of the comparator and the output terminal of the comparator, and the two ends of the seventh resistor are respectively connected to the positive input terminal of the comparator and the output terminal of the comparator; One end of the eighth resistor is connected to the positive power supply terminal, and the other end is connected to the base of the first transistor; One end of the ninth resistor is connected to the negative power supply end, and the other end is connected to the base of the first transistor; The anode of the first diode is connected to the base of the first transistor, and the cathode is connected to the emitter of the first transistor; The collector of the first transistor is connected to one end of the tenth resistor, the other end of the tenth resistor is connected in series with the eleventh resistor and then grounded, and the other end of the tenth resistor is connected to the output end of the polarity discrimination circuit; The two input ends of the current sensing monitor are respectively connected to the two ends of the eleventh resistor, and the output end of the current sensing monitor is connected to the input end of the analog-to-digital converter; The output end of the analog-to-digital converter is connected to the logic control module as the output end of the current range discrimination circuit.

8. The beam integrator according to claim 1, characterized in that: Each of the integration modules further includes: a driving circuit for stabilizing the square wave signal and inputting the stabilized square wave signal into the logic control module.

9. The beam integrator according to claim 8, characterized in that: The driving circuit includes: an AND gate, a second triode, a second diode, a thirteenth resistor and a fourteenth resistor, the first input end of the AND gate is connected to the positive power supply end through the thirteenth resistor, the second input end of the AND gate is connected to the output end of the integration circuit, the output end of the AND gate is connected to the base of the second triode, the collector of the second triode is connected to the positive power supply end, the emitter is connected to the first end of the fourteenth resistor, the second end of the fourteenth resistor is grounded, the anode of the second diode is connected to the emitter of the second triode, the cathode is connected to the base of the second triode, and the first end of the fourteenth resistor is the output end of the driving circuit connected to the logic control module.

10. The beam integrator according to any one of claims 1 to 9, characterized in that: Also includes: A mother circuit board and at least one sub-circuit board, the logic control module is arranged on the mother circuit board, the integration module is arranged on the sub-circuit board, and the sub-circuit board is detachably connected to the mother circuit board.

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