Slow start high voltage circuit suitable for silicon detectors with various sensitive layer thicknesses

Abstract

The application provides a slow start high-voltage circuit suitable for silicon detectors with various sensitive layer thicknesses, in a high-frequency oscillation circuit, when a transistor is turned on, an induced electromotive force is generated in a primary coil of a transformer, when the transistor is saturated, the induced electromotive force generated in the primary coil of the transformer prevents the decrease of current, thereby a circulating oscillation signal is formed, after the power supply is powered on, the voltage can be adjusted through the adjustment of an RC circuit; a voltage doubling rectifier circuit doubles the oscillation signal; the slow start circuit adjusts the time length of slow start through an RC time constant circuit, the time length of power supply to the silicon detector is delayed after the RC time constant circuit is powered on through a field effect transistor, the impact current when the power supply is powered on is reduced through the slow start circuit, the output current is extremely small, is a microampere level current, the detector can work in a full depletion state, and is suitable for systems with high power consumption requirements.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silicon detector starting circuit, and particularly relates to a slow-start high-voltage circuit suitable for silicon detectors with various thicknesses of sensitive layers. BACKGROUND

[0002] The statements in this section merely provide background information related to the application and do not necessarily constitute prior art.

[0003] The space radiation environment is one of the important challenges faced by space exploration and manned space flight. High-energy charged particles have the potential to damage the human body, electronic components and spacecraft materials, which may lead to spacecraft failure and affect the health and safety of astronauts. Therefore, it is crucial to reduce or eliminate the harm of these radiations to spacecraft materials and astronauts, and it is also an important prerequisite for further scientific research.

[0004] In the field of space exploration, it is crucial to choose the right semiconductor material to effectively detect charged particles. Although the high-purity germanium (Ge) detector has excellent energy resolution, its narrow band gap means that it usually needs to work at low temperature, which limits its application in portable detection devices. Although the CdTe detector works well at room temperature, it has poor radiation resistance and is easily damaged under high-dose radiation, affecting its performance. The CZT detector is favored due to its excellent room temperature detection performance and strong radiation resistance, but incomplete charge collection may cause energy spectrum tailing, affecting energy resolution, and the effective detection area will decrease at lower temperatures, affecting overall performance.

[0005] Si detectors have been widely used in portable instruments, satellite communications and high-energy physics experiments due to their low density, small leakage current, small size and high energy resolution. In the field of charged particle detection, Si has much better performance than CZT.

[0006] Si detectors use high-doped semiconductor materials to make crystal diodes, and by applying a reverse bias voltage, the voltage is mainly concentrated in the depletion layer, thereby expanding the sensitive area of the detector. When charged particles enter the sensitive area of the detector, they collide with atoms in the crystal and lose energy. These energy losses cause electrons to transition from the valence band to the conduction band, generating electron-hole pairs. Under the action of the electric field, electrons and holes drift towards the anode and cathode, respectively, forming a current signal. The size of the charge signal output by the detector is proportional to the energy lost by the charged particles in the sensitive area. Therefore, by measuring the amplitude or width of the pulse signal, the energy of the charged particles can be inverted.

[0007] But the current common high-voltage circuit cannot adapt to the silicon detector of various sensitive layer thickness, there are resource redundancy, high power consumption, high voltage is not adjustable, the starting circuit time is not adjustable and other problems. SUMMARY

[0008] In order to overcome the above-mentioned deficiencies of the prior art, the application provides a slow start high-voltage circuit suitable for silicon detectors of various sensitive layer thickness, which has the advantages of low power consumption, adjustable high voltage and starting time.

[0009] To achieve the above object, the first aspect of the application provides a slow start high-voltage circuit suitable for silicon detectors of various sensitive layer thickness, comprising:

[0010] The high-frequency oscillation circuit comprises a transformer, an RC circuit and a triode; the primary coil of the transformer is connected with the emitter of the triode, the two input ends of the auxiliary coil of the transformer are connected with the base and the collector of the triode respectively, the collector of the triode is connected with the RC circuit, and the RC circuit is connected with the power supply; the primary coil is used to generate an induced electromotive force when the triode is turned on or saturated, forming an oscillation signal;

[0011] The voltage doubling rectifier circuit comprises a capacitor and a diode connected with the secondary coil of the transformer, and is used for voltage doubling processing of the oscillation signal;

[0012] The slow start circuit comprises a field effect tube, an RC time constant circuit connected with the field effect tube, and the RC time constant circuit is connected with the capacitor and the diode; the field effect tube is used to delay the power-on time of the silicon detector after the RC time constant circuit is powered on;

[0013] When the power supply is powered on, the output voltage of the primary coil of the transformer is changed by adjusting the resistance value of the RC circuit to realize voltage adjustment; the slow start time is adjusted by adjusting the time constant of the RC time constant circuit.

[0014] The above one or more technical solutions have the following beneficial effects:

[0015] In the application, the high-frequency oscillation circuit, the voltage doubling rectifier circuit and the slow start circuit are included, the high-frequency oscillation circuit includes the transformer, the RC circuit and the triode, when the triode is turned on, the primary coil of the transformer generates the induced electromotive force, when the triode is saturated, the primary coil of the transformer generates the induced electromotive force to prevent the current from reducing, thereby the oscillation signal is cyclically formed, after the power supply is powered on, the voltage adjustment can be realized through the adjustment of the RC circuit; the voltage doubling rectifier circuit includes the capacitor and the diode, and the oscillation signal is subjected to the voltage doubling treatment; the slow start circuit adjusts the time length of the slow start through the RC time constant circuit, the time length of the power supply to the silicon detector is delayed through the field effect tube after the RC time constant circuit is powered on, the impact current when the power supply is powered on is reduced through the slow start circuit, the output current is extremely small, the current is the microampere level, the detector is ensured to work in the full depletion state, and the application is suitable for the system with high power consumption requirement.

[0016] The advantages of the additional aspects of the application will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0017] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application given below, explain the application, and do not constitute an improper limitation of the application.

[0018] Figure 1 It is slow start high voltage circuit diagram in the embodiment one of the application;

[0019] Figure 2 It is Si detector bias voltage and current simulation diagram in the embodiment one of the application;

[0020] Figure 3 It is start time schematic diagram in the embodiment one of the application;

[0021] Figure 4 It is dark current change curve diagram in the embodiment one of the application;

[0022] Figure 5 It is Si detector preamplifier output waveform diagram in the embodiment one of the application;

[0023] Figure 6 It is energy spectrum measurement diagram in the embodiment one of the application. DETAILED DESCRIPTION

[0024] It should be noted that the following detailed description is exemplary, and is intended to provide further explanation of the application. Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0025] It is to be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application.

[0026] In the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0027] Embodiment one

[0028] The embodiment discloses a slow start high voltage circuit suitable for silicon detectors with various sensitive layer thicknesses, comprising:

[0029] The high frequency oscillation circuit comprises a transformer, an RC circuit and a triode; a primary coil of the transformer is connected with an emitter of the triode, two input ends of an auxiliary coil of the transformer are connected with a base and a collector of the triode respectively, the collector of the triode is connected with the RC circuit, and the RC circuit is connected with a power supply; the primary coil is used for generating an induced electromotive force when the triode is turned on or saturated, so as to form an oscillation signal;

[0030] The voltage doubling rectifier circuit comprises a capacitor and a diode connected with a secondary coil of the transformer, and is used for carrying out voltage doubling processing on the oscillation signal;

[0031] The slow start circuit comprises a field effect tube, an RC time constant circuit connected with the field effect tube, and the RC time constant circuit is connected with the voltage doubling rectifier circuit; the field effect tube is used for delaying the power supply time length of the silicon detector after the RC time constant circuit is powered on;

[0032] When the power supply is powered on, the output voltage of the primary coil of the transformer is changed by adjusting the RC circuit, so that voltage adjustment is realized; the slow start time is adjusted by adjusting the RC time constant circuit.

[0033] In the embodiment, the high frequency oscillation circuit and the voltage doubling rectifier circuit are used to provide a bias voltage for Si; the high frequency oscillation circuit converts direct current of a battery into high frequency alternating current, and then outputs direct current via the voltage doubling rectifier circuit; the voltage doubling rectifier circuit outputs a very small current, and due to high input voltage, there is a large capacitor in the power supply circuit for filtering and preventing DIP; when a single board is inserted and powered on, an impact on the power supply is caused, a large instantaneous current will cause a drop of the power supply voltage, and the normal work of other single boards can be affected; at the same time, due to the large instantaneous current, a significant sparking phenomenon occurs on the connector when the single board is inserted, which causes electromagnetic interference and corrosion of the connector; in order to avoid the above phenomenon, the slow start circuit is added to the high voltage circuit.

[0034] The slow start high voltage circuit suitable for silicon detectors with various sensitive layer thicknesses provided by the embodiment is not only adjustable in high voltage range (30V-1000V), but also reduces the impact current when the power is turned on through the slow start design, the whole machine power consumption is only 3.3mW, the start time is adjustable from 100us-2s, the high voltage circuit design dedicated to particle radiation detectors provides an efficient tool that can be carried and measured in real time for astronauts.

[0035] The slow start high voltage circuit suitable for silicon detectors with various sensitive layer thicknesses provided by the embodiment is not only adjustable in high voltage range (30V-1000V), but also reduces the impact current when the power is turned on through the slow start design, the whole machine power consumption is only 3.3mW, the start time is adjustable from 100us-2s, the high voltage circuit design dedicated to particle radiation detectors provides an efficient tool that can be carried and measured in real time for astronauts. Figure 1 The slow start high voltage circuit suitable for silicon detectors with various sensitive layer thicknesses provided by the embodiment is not only adjustable in high voltage range (30V-1000V), but also reduces the impact current when the power is turned on through the slow start design, the whole machine power consumption is only 3.3mW, the start time is adjustable from 100us-2s, the high voltage circuit design dedicated to particle radiation detectors provides an efficient tool that can be carried and measured in real time for astronauts.

[0036] In the embodiment, the high-frequency oscillation circuit includes a transformer T1 and a triode Q2, and a transformer dedicated to the high-voltage part of the particle radiation detector is specially designed. The transformer T1 includes a primary coil, an auxiliary coil and a secondary coil.

[0037] Specifically, the collector of the triode Q2 is connected with the power supply and the same end of the auxiliary coil, respectively, the emitter of the triode Q2 is connected with the different end of the primary coil, the base of the triode Q2 is connected with the different end of the auxiliary coil, and the same end of the primary coil is grounded.

[0038] The second resistor R2 is connected in series between the collector of the triode Q2 and the same end of the auxiliary coil, and the first resistor R1 is connected in series between the collector of the triode Q2 and the power supply.

[0039] The first end of the first resistor R1 is connected with the first end of the fourth capacitor C4, the second end of the first resistor R1 is connected with the power supply, and the second end of the fourth capacitor C4 is grounded.

[0040] According to the inductance's characteristic of keeping or changing: when the current flowing through the inductor increases, the inductor will generate an induced electromotive force to hinder the increase of the current; when the current flowing through the inductor decreases, the inductor will generate an induced electromotive force to hinder the decrease of the current. When the current flowing through the inductor is constant, the inductor will not generate an induced electromotive force.

[0041] The transformer has three coils: the primary coil (5th pin, 6th pin), the auxiliary coil (3rd pin, 4th pin) and the secondary coil (1st pin, 2nd pin). Each coil is equivalent to an inductor, and the induced electromotive force can be transmitted from the primary coil to the auxiliary coil and the secondary coil. The same end of the transformer T1 is the 2nd pin, the 3rd pin and the 5th pin marked with a blue dot, and the induced electromotive forces of the same ends between different coils have the same polarity.

[0042] When the direct current voltage of the VCC is applied, the current flows through the first resistor R1, the second resistor R2 and the auxiliary coil, and then flows into the GND through the emitting junction of the transistor. In this process, the transistor Q2 is turned on, and the current flows through the primary coil and the collector and the emitter of the transistor Q2, and finally reaches the GND; this current is greater than the current flowing through the emitting junction of the transistor, and since the current of the primary coil increases, the induced electromotive force of the upper negative and lower positive is generated to prevent the increase of the current, and the auxiliary coil generates the induced electromotive force of the upper negative and lower positive, which further increases the current of the emitting junction of the transistor, and the circuit enters positive feedback. When the current between the collector and the emitter of the transistor Q2 increases to a certain extent, the transistor Q2 is saturated, and the current no longer increases, and at this time the induced electromotive force of the coil disappears. Since the induced electromotive force of the emitting junction of the transistor disappears, the current flowing through the emitting junction decreases, so the current flowing through the collector and the emitter also decreases, and at this time the induced electromotive force of the upper positive and lower negative of the primary coil is generated to prevent the decrease of the current, and the induced electromotive force of the upper positive and lower negative of the auxiliary coil is generated to increase the current of the emitting junction, and then to increase the current flowing through the primary coil and the collector and the emitter of the transistor Q2, and the positive feedback is entered again. The two processes are in turn circulated, and the oscillation signal is generated on the primary coil, and then transmitted to the secondary coil.

[0043] In the embodiment, the voltage doubling rectifier circuit comprises a first capacitor C1, a fifth capacitor C5, a third diode D3 and a fourth diode D4; the first capacitor C1 and the fifth capacitor C1 are connected with the high-frequency oscillation circuit respectively, and the third diode D3 and the fourth diode D4 are connected in parallel with the high-frequency oscillation circuit.

[0044] Specifically, a first end of the first capacitor C1 is connected to a non-name end of the secondary coil, a second end of the first capacitor C1 is connected with a positive electrode of the third diode D3, a negative electrode of the fourth diode D4 and a positive electrode of the first diode D1 respectively; a negative electrode of the third diode D3 is connected with a first end of the fifth capacitor C5, a positive electrode of the fourth diode D4 is connected with a second end of the fifth capacitor C5, the first end of the fifth capacitor C5 is connected with a name end of the secondary coil, and the second end of the fifth capacitor C5 is grounded.

[0045] A negative electrode of the first diode D1 is connected with a first end of the third resistor R3, a second end of the third resistor R3 is connected to a first end of the second capacitor C2, a second end of the second capacitor C2 is grounded, and the second end of the third resistor R3 and the first end of the second capacitor C2 are connected to a first end of the thirteenth resistor R13 respectively.

[0046] Voltage multiplier rectifier circuits primarily utilize the unidirectional conduction characteristic of diodes (equivalent to switches) and the voltage across capacitors' instability and energy storage capabilities. This allows energy to be gradually transferred to subsequent stages, while the voltage on the line gradually increases, resulting in voltage multiplier, tripler, and higher voltage multiplier rectifier circuits. However, because voltage multiplier rectifier circuits consist only of diodes and capacitors, they can only be used in low-current, high-voltage environments and are not suitable for high-current, high-voltage environments. Silicon detectors, for example, fall into this category of low-current, high-voltage environments.

[0047] The voltage across the primary winding of transformer T1 is converted to the voltage across the secondary winding U. 12 At that time, in U 12 During the first positive half-cycle, the third diode D3 is turned on, and the fourth diode D4 is turned off, charging the first capacitor C1. After charging is complete, U c1 =U 12 . in U 12 During the first negative half-cycle, the third diode D3 is cut off, and the fourth diode D4 is turned on, charging the fifth capacitor C5. After charging is complete, U c5 =U 12 . in U 12 During the second positive half-cycle, the secondary coil U 12 The first capacitor C1 and the second capacitor C2 are charged together. After charging is complete, U c2 =2U 12 . in U 12 During the second negative half-cycle, the secondary coil U 12 The fifth capacitor C5 and the second capacitor C2 are charged together. After charging is complete, U c2 =2U 12 This makes full use of the secondary coil U 12 The positive and negative half-cycles maximize the voltage multiplier efficiency.

[0048] In this embodiment, the soft-start circuit includes a fourth resistor R4 and a third capacitor C3 connected in parallel, and a field-effect transistor Q1; the source of the field-effect transistor Q1 is connected to the first terminal of the fourth resistor R4 and the third capacitor C3, and the gate of the field-effect transistor Q1 is connected to the second terminal of the fourth resistor and the third capacitor.

[0049] Specifically, the first end of the fourth resistor R4 and the first end of the third capacitor C3 are respectively connected to the first end of the thirteenth resistor R13, and the second end of the fourth resistor R4 and the second end of the third capacitor C3 are respectively connected to the first end of the fifth resistor R5.

[0050] A second diode D2 is connected in parallel with the fourth resistor R4 and the third capacitor C3. The cathode of the second diode D2 is connected to the second terminal of the thirteenth resistor R13, and the anode of the second diode D2 is connected to the first terminal of the fifth resistor R5.

[0051] Specifically, the positive pole of the third capacitor C3 is connected with the second end of the thirteenth resistor R13, and the negative pole of the third capacitor C3 is connected with the first end of the fifth resistor R5.

[0052] The gate of the field effect tube Q1 is connected with the first end of the fifth resistor R5, and the second end of the fifth resistor R5 is grounded.

[0053] In the embodiment, the field effect tube Q1 can be an N-channel enhancement mode field effect tube.

[0054] The soft start circuit is composed of R4, R5, C3 and Q1, Q1 is an insulated gate field effect tube MOS, which is the most critical device of the soft start circuit. The resistor R4, R5 and C3 constitute a voltage dividing RC time constant circuit, and C3 is connected in parallel between the GS poles of Q1, that is, Vc3=Vgs. When the power supply is just added to the single board, C3 is not charged, Vgs=0, MOS is not conductive, and the high voltage module does not supply power externally. Subsequently, the power supply charges C3 through R4 and R5, and when the voltage of C3 reaches Vth, the MOS starts to conduct. In this stage, the delay time is estimated by the following formula: Uin(R4 / (R4+R5))(1-e -T / τ )=Vth, wherein T is the delay time, Uin is the input voltage, τ is the time constant of the RC circuit, τ is equal to C3×(R4 / / R5), and Vth is the opening voltage of the MOS tube Q1.

[0055] After the MOS tube starts to conduct, Vgs continues to increase, the on-resistance Rds rapidly decreases, and the output voltage of the soft start gradually rises until it is basically consistent with the input voltage. The high voltage module starts to work, and the single board is formally powered on. In this process, the output voltage is not instantaneously jumped to the highest, so the interference of the inrush current is greatly reduced. The time of this process is related to the charging speed of C3, the characteristics of MOS, and the load characteristics, and specific adjustment needs to be measured.

[0056] The bias voltage required by the silicon detector, that is, the high voltage, requires that the rising rate be less than 1kV / s. That is, the soft start circuit of the design needs to meet this requirement. The measured time for rising to 125V without using the soft start circuit is 60ms, and the time for rising to 125V after adding the soft start circuit is 1.675s, which meets the requirements of the silicon detector for the power-on time.

[0057] The voltage of the embodiment has three levels of regulation, which are realized by adjusting the resistance R1 of the RC circuit and the resistance R2 of the auxiliary coil input end to regulate the voltage on the primary coil side. Through the turns ratio of the primary and secondary coils of the transformer, the voltage on the secondary coil is calculated, and then the third level of voltage regulation is realized through the subsequent voltage doubling rectifier circuit.

[0058] The starting time of the embodiment has two-stage regulation, which is, the first stage is the size of the output stage R3 and C2 of the front stage, increasing the resistance value of R3 and the capacitance value of C2 to slow down the time constant supplied to the post-stage slow-starting circuit. The second stage is the slow-starting circuit itself, which changes the divided voltage RC time constant by adjusting the size of R4, R5 and C3, thereby realizing adjustable starting time.

[0059] The transformer is used to realize the transmission of electric energy according to the principle of electromagnetic induction. In the embodiment, the magnetic core is made of PC95 material with high magnetic permeability and low loss. The coil is made of copper with good electrical conductivity and mechanical strength, and the skeleton is made of GU11 without pin. The single-layer winding tail is folded back by 90°, and a layer of insulating tape is laid under it. The length of all the flying wires of the winding is 30 mm, and all the tail wires are provided with equal-length sleeves and the magnetic core is fixed after being glued and then dipped in paint. The withstand voltage of the magnetic core and the coil is as high as 1000V, so as to adapt to high-voltage output. In order to ensure enough space to accommodate the coil and make the whole transformer smaller, the size of the iron core is designed to be not more than 0.5*0.5*1mm. A sufficient insulation layer is designed between the primary and secondary coils to prevent electrical breakdown. It is ensured that there is sufficient insulation distance between the coil and the magnetic core. Lead shielding is used on the periphery of the transformer to reduce the radiation effect, and radiation-hardened insulation materials are selected considering the influence of radiation on the insulation materials.

[0060] The transformer for the high-voltage part of the particle radiation detector in the embodiment has the following advantages compared with other ordinary transformers:

[0061] (1) Since the silicon detector works in full depletion mode with different thickness of the sensitive layer, the required high voltage increases with the increase of the thickness of the sensitive layer. The high voltage required by the commonly used thickness of the silicon detector is in the range of 45V-125V, and the maximum withstand voltage of the transformer in the embodiment is as high as 1000V, which can not only meet the requirements of more thickness of the sensitive layer of the silicon detector, but also be applied to the tellurium zinc cadmium CZT detector which requires a voltage of more than 800V.

[0062] (2) Since the circuit in the embodiment is finally applied in space load and portable instruments worn on the body, the protection of the devices in the circuit itself also needs to be considered. Therefore, the transformer in the embodiment is not a transformer with only a primary coil and a secondary coil, but a transformer composed of a primary coil, an auxiliary coil and a secondary coil, and the turn ratio of the primary coil, the auxiliary coil and the secondary coil is 8:22:50. The auxiliary coil is used to connect the circuit of the primary coil, and the auxiliary coil in the primary can provide a voltage source and a feedback signal for the protection of the transformer. Through the feedback of the auxiliary coil, the internal power supply can be stabilized. In addition, when the secondary coil is overloaded, the current will be too large, which will cause the secondary coil to be insufficient in carrying capacity, thereby causing the output voltage of the secondary coil to drop, and the output voltage of the auxiliary coil also drops. When it drops to a certain extent, the oscillation circuit cannot start, thereby protecting the switch tube.

[0063] (3) Spaceborne and portable wearing instruments such as personal dosimeters are very sensitive to weight and volume. The volume of the transformer of the embodiment is about 10*10*10mm, and the weight is about 1g. The small volume and light weight are very suitable for spaceborne and scenes where the volume and weight of the instrument are strictly required.

[0064] In the embodiment, taking 30V as an example, the transistor Q2 and the transformer T1 constitute a high-frequency oscillator, which converts 3V direct current into 18KHz high-frequency alternating current. The high-frequency alternating voltage is converted into direct current voltage through the voltage doubling rectifier circuit composed of the first capacitor C1 and the fifth C5, the first diode D1, the third diode D3 and the fourth diode D4, and then slowly rises to 30V through the slow start circuit composed of the fourth resistor R4 and the fifth R5, the third capacitor C3 and the MOS tube Q1, so as to ensure that the detector works in a full depletion state, and the output current is extremely small, which is microampere level current, and is suitable for systems with high power consumption requirements.

[0065] The Si detector bias voltage circuit is simulated by the SIMetrix software, and the test conditions are: input voltage V1=3V, the number of turns of the transformer and other circuit component parameters are set, and the voltage and current simulation output schematic diagram is as shown in Figure 2 .

[0066] As shown in Figure 3 , the simulation results show that the output voltage rises to 30V within 12s and tends to be stable, and the output current rises to 60μA at the moment of power-on, and is less than 1μA after the voltage tends to be stable. The actual test of the working voltage of the Si detector shows that the voltage is 30V tested by the oscilloscope after power-on, and does not need to wait for 12s, which can provide stable voltage for the system.

[0067] In order to verify whether the Si detector can work normally and test its performance, the Si dark current and energy spectrum are tested in the embodiment, and the test instruments include a high-voltage module, a Si detector, an oscilloscope, an amplifier and an upper computer, etc.

[0068] Since the Si detector is extremely sensitive to light, the light needs to be shielded (non-vacuum) during testing. The radioactive source adopts 241Am, which is spaced about 1cm from the Si surface, and a 30V bias is applied. The input and output signal lines are transmitted by shielded wires.

[0069] The actual test of the change of the Si detector dark current with the increase of the bias voltage is compared with the test report provided by Chengdu Jingwei, as shown in Figure 4 . The energy spectrum is tested by using the alpha radioactive source 241Am, and the Si detector is connected to the preamplifier of mystec. The preamplifier output waveform is as shown in Figure 5 .

[0070] Depend on Figure 4 It can be seen that the actual dark current leakage current under the normal operating voltage of 30 V is 46 nA, which is greater than the data provided by Sichuan Chengdu Jingwei Technology Co., Ltd. It may be due to the non-vacuum test environment causing the dark current to increase, but the impact is not significant.

[0071] The energy spectrum obtained from the host computer is as follows: Figure 6 As shown, the test results indicate that the dark current of the Si detector is normal, and the calculated energy resolution in air is approximately 2.0%.

[0072] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A soft-start high-voltage circuit suitable for silicon detectors with various sensitive layer thicknesses, characterized in that, include: High-frequency oscillation circuit, voltage doubler rectifier circuit, and soft-start circuit; The high-frequency oscillation circuit includes a transformer, an RC circuit, and a transistor; the primary coil of the transformer is connected to the emitter of the transistor, the two input terminals of the auxiliary coil of the transformer are respectively connected to the base and collector of the transistor, the collector of the transistor is connected to the RC circuit, and the RC circuit is connected to a power supply; the primary coil is used to generate an induced electromotive force when the transistor is turned on or saturated, thereby forming an oscillation signal; The voltage doubler rectifier circuit includes a capacitor and a diode connected to the secondary coil of the transformer, used to double the voltage of the oscillation signal; The soft-start circuit includes a field-effect transistor (FET), an RC time constant circuit connected to the FET, and the RC time constant circuit connected to the voltage doubler rectifier circuit; the FET is used to delay the power-on time of the silicon detector after the RC time constant circuit is powered on. When the power supply is powered on, the output voltage of the primary coil of the transformer is adjusted by changing the resistance value of the RC circuit to achieve voltage regulation, and the soft start time is adjusted by adjusting the time constant of the RC time constant circuit.

2. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 1, characterized in that, The collector of the transistor is connected to the same-name terminal of the power supply and the auxiliary coil, the emitter of the transistor is connected to the opposite-name terminal of the primary coil, and the base of the transistor is connected to the opposite-name terminal of the auxiliary coil.

3. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 2, characterized in that, The RC circuit includes a first resistor, a fourth capacitor, and a second resistor; the collector of the transistor is connected to the first terminal of the fourth capacitor, and the second terminal of the fourth capacitor and the corresponding terminal of the primary coil are respectively grounded; the two ends of the second resistor are respectively connected to the collector of the transistor and the corresponding terminal of the auxiliary coil.

4. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 1 or 2, characterized in that, The voltage doubler rectifier circuit includes a first capacitor, a fifth capacitor, a third diode, and a fourth diode; the first capacitor and the fifth capacitor are respectively connected to the high-frequency oscillation circuit, and the third diode and the fourth diode are connected in parallel to the high-frequency oscillation circuit.

5. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 4, characterized in that, The first terminal of the first capacitor is connected to the opposite terminal of the secondary coil, and the first terminal of the fifth capacitor and the negative terminal of the third diode are respectively connected to the same terminal of the secondary coil; the negative terminal of the third diode and the positive terminal of the fourth diode are respectively connected to the two ends of the fifth capacitor.

6. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 4, characterized in that, The voltage doubler rectifier circuit further includes a first diode and a third resistor connected in series, and a second capacitor; the negative terminal of the fourth diode is connected to the positive terminal of the first diode; the first terminal of the second capacitor is connected to the third resistor, and the second terminal of the second capacitor is grounded to the positive terminal of the fourth diode.

7. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 1, characterized in that, The RC time constant circuit includes a fourth resistor and a third capacitor connected in parallel, as well as a fifth resistor; the source of the field-effect transistor is connected to the first terminal of the fourth resistor and the third capacitor, the gate of the field-effect transistor is connected to the second terminal of the fourth resistor and the third capacitor, and the gate of the field-effect transistor is connected to the fifth resistor and then grounded.

8. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 7, characterized in that, The soft-start circuit also includes a second diode, which is connected in parallel with the fourth resistor and the third capacitor.

9. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 1, characterized in that, The transformer is surrounded by a lead shielding layer.

10. The soft-start high-voltage circuit for silicon detectors with various sensitive layer thicknesses as described in claim 1, characterized in that, A resistor is connected in series between the voltage doubler rectifier circuit and the soft-start circuit.

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