Automatic testing method and system for plateau curve of gamma sensor

Abstract

The invention discloses an automatic test method and system for a plateau curve of a gamma sensor, and relates to the technical field of automatic test.A controller is used for outputting a PWM signal with the fixed frequency and the slowly-adjusted duty ratio, then the PWM signal is converted into dynamically-changed gamma sensor input high voltage, and working voltage is provided for the gamma sensor; processing an electric pulse signal output by the gamma sensor, and converting the electric pulse signal into a square wave signal which can be identified by a controller; the controller collects rising edges of the square wave signals, each rising edge is recorded as a gamma electric pulse signal, and the gamma electric pulse signals in unit time are accumulated to obtain a group of gamma electric pulse count values; the controller acquires gamma electric pulse count values output by the gamma sensor in unit time under different temperatures and different input high voltages, and gathers the gamma electric pulse count values to obtain a gamma sensor plateau curve. According to the method, the plateau curve of the gamma sensor can be conveniently and quickly obtained.

Description

Technical Field

[0001] This invention relates to the field of automated testing technology, specifically to an automated testing method and system for gamma sensor plateau curves. Background Technology

[0002] The gamma sensor is the core component of an azimuth gamma instrument, providing feedback on the intensity of gamma rays in the environment to inform geological formations. The stronger the gamma rays, the more electrical pulse signals the sensor outputs. These electrical pulse signals are converted into square wave signals by a circuit, with each pulse corresponding to a square wave. The microcontroller collects these square wave signals and calculates the electrical pulse signal per unit time to determine the intensity of the gamma rays.

[0003] However, the number of electrical pulses produced by a gamma sensor per unit time is affected by both the input high voltage and the ambient temperature. Therefore, each gamma sensor has a high voltage range within which the number of electrical pulses output is stable, and within this range, the number of electrical pulses output by the gamma sensor does not change significantly with temperature variations.

[0004] The gamma sensor plateau curve refers to the curve formed by observing the count rate (counts occurring per unit time) obtained by a calibrator under the condition of a constant number of particles by changing the high voltage value applied between the electrodes of the counter tube. See also Figure 1 The horizontal axis represents the high voltage input to the gamma sensor, and the vertical axis represents the number of electrical pulse signals per unit time. Curve 1 (green) and curve 3 (blue) are plateau curves at 25℃, and curve 2 (red) is the plateau curve at 150℃. From these two sets of plateau curves, it can be seen that the number of output electrical pulse signals is stable when the high voltage input to the gamma sensor is within the range of 1500–1675V.

[0005] Because different electrical pulse signal processing schemes result in different gamma sensor plateau curves, how to conveniently and quickly obtain gamma sensor plateau curves adapted to different electrical pulse signal processing schemes is an urgent problem to be solved. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides an automated testing method and system for gamma sensor plateau curves, which facilitates the acquisition of gamma pulse counts output by the gamma sensor per unit time under different temperatures and input high voltages, and the summarization of these counts to obtain the gamma sensor plateau curves.

[0007] This invention protects an automated testing method for the plateau curve of a gamma sensor. It utilizes a controller to output a PWM signal with a fixed frequency and a slowly adjusted duty cycle, and then converts the PWM signal into a dynamically changing high voltage input to the gamma sensor to provide the operating voltage for the gamma sensor. At the same time, the high voltage input is converted into an analog signal that can be recognized by the controller's ADC module. The controller monitors the high voltage input and dynamically adjusts the duty cycle of the PWM signal to ensure that the high voltage input is within a set range.

[0008] The electrical pulse signal output by the gamma sensor is processed and converted into a square wave signal that the controller can recognize. The controller collects the rising edge of the square wave signal, and each rising edge is recorded as a gamma electrical pulse signal. The gamma electrical pulse signals in a unit time are accumulated to obtain a set of gamma electrical pulse count values.

[0009] During the test, the required temperature environment is provided, and the operating temperature of the gamma sensor is monitored in real time.

[0010] The controller collects the gamma pulse count values ​​output by the gamma sensor per unit time under different temperatures and different input high voltages, and summarizes them to obtain the gamma sensor plateau curve.

[0011] In one embodiment of the present invention, the duty cycle of the PWM signal is slowly increased in units of 0.1%. When the input high voltage monitored by the controller in real time reaches each preset voltage value, the duty cycle of the PWM signal remains unchanged for a certain period of time, which facilitates the accumulation of gamma pulse count values.

[0012] In one embodiment of the present invention, the input high voltage is adjusted within the range of 1300 to 1700V, and the high voltage adjustment interval is 50V.

[0013] In one embodiment of the present invention, before the test begins, multiple low duty cycle PWM signals are selected for functional self-test, and the input voltage of the gamma sensor corresponding to the low duty cycle PWM signal does not exceed 1000V; the gamma pulse count value, gamma sensor input high voltage, and temperature under different low duty cycles are uploaded to the PC to verify whether the data is normal.

[0014] After the function self-test is successful, connect the gamma sensor and start the temperature check. Sample the temperature every few seconds. Collect the working temperature of the gamma sensor and the ambient set temperature N times in a row. After confirming that the error does not exceed the allowable range, start the test and accumulate the gamma pulse count value. After each set of gamma pulse count values ​​is collected, upload the high voltage input of the gamma sensor and the gamma pulse count value to the PC. Continue until the preset maximum value of the high voltage input of the gamma sensor has also been tested.

[0015] Adjust the ambient temperature setting and repeat the above test process.

[0016] This invention also protects an automated testing system for gamma sensor plateau curves, and based on the above-mentioned automated testing method for gamma sensor plateau curves, includes:

[0017] The electrical pulse signal processing circuit is used to convert the electrical pulse signal output by the gamma sensor into a square wave signal that can be recognized by the main controller.

[0018] The main controller is used to output a PWM signal with a fixed frequency and a slowly adjusted duty cycle. At the same time, it acquires the high voltage input from the gamma sensor, acquires the square wave signal output from the electrical pulse signal processing circuit, and detects the gamma electrical pulse count value per unit time.

[0019] High-voltage circuitry is used to convert external power into dynamically changing gamma sensor input high voltage based on PWM signals.

[0020] The negative high voltage acquisition circuit is used to reverse and reduce the high voltage input from the gamma sensor and send it to the main controller ADC module.

[0021] High-temperature chambers are used to provide different test temperatures;

[0022] Temperature sensor is used to detect the operating temperature of gamma sensor and the set temperature of high temperature chamber, and transmit the data to the main controller;

[0023] An external reference voltage circuit is used to provide a reference voltage for system operation;

[0024] The serial port circuit is used for debugging and is connected to the PC for transmitting debugging data.

[0025] In one embodiment of the present invention, the electrical pulse signal processing circuit uses a precision sampling resistor and a current sensing amplifier to convert the negative polarity current pulse signal output by the gamma sensor into a negative polarity voltage pulse signal, wherein the precision sampling resistor is composed of two precision resistors connected in parallel; and then outputs a square wave signal through a voltage follower and a hysteresis comparator.

[0026] In one embodiment of the present invention, the negative polarity current pulse signal output by the gamma sensor passes through the protection resistor R120 from the current sensing amplifier V. IN+ Pin input, from V IN- The pin outputs through the protection resistor R47, and the precision sampling resistor is connected to V. IN+ pin and V IN- Between the pins, the OUT pin outputs a negative polarity voltage pulse signal; V IN+ pin and V IN- A capacitor C5 is connected between the pins.

[0027] In one embodiment of the present invention, the high-voltage circuit includes:

[0028] The PWM driver and power switching unit is used to convert the PWM signal into a switching signal that can efficiently drive the power transformer.

[0029] The boost unit mainly consists of a power transformer and a voltage multiplier circuit, used for electrical isolation and voltage boosting, and outputs high voltage to the gamma sensor input.

[0030] In one embodiment of the present invention, the negative high voltage acquisition circuit reduces the high voltage input from the gamma sensor in reverse, converts it into a positive voltage, and then outputs it to the main controller ADC module after RC filtering; the main controller monitors the input high voltage and dynamically adjusts the duty cycle of the output PWM signal to ensure that the input high voltage is within the set range.

[0031] The beneficial effects of this invention are:

[0032] 1. An automated testing method and system for gamma sensor plateau curves is proposed, which can conveniently and quickly obtain gamma sensor plateau curves;

[0033] 2. Before connecting the gamma sensor, perform a function self-test. 7. After confirming that the function test is correct, connect the gamma sensor. This can effectively protect the gamma sensor.

[0034] 3. High-voltage circuit scheme: The input high voltage is adjusted by PWM signal to provide different input voltages for the gamma sensor. The scheme is simple and highly flexible.

[0035] 4. An external reference voltage chip is used to provide a high-precision ADC reference voltage, ensuring the accuracy of the input high voltage and test temperature;

[0036] 5. It can be used with different electrical pulse signal processing circuits, and has high compatibility;

[0037] 6. The provided electrical pulse signal processing circuit can improve the long-term reliability and measurement stability of the system in harsh environments such as high temperature. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the gamma sensor plateau curve;

[0039] Figure 2 The flowchart shows the automated testing method for the gamma sensor plateau curve disclosed in Example 1.

[0040] Figure 3 This is a circuit diagram of a signal conversion and amplification unit based on a current-sensing amplifier in an electrical pulse signal processing circuit.

[0041] Figure 4 This is the circuit schematic of the analog-to-digital conversion unit in an electrical pulse signal processing circuit.

[0042] Figure 5 This is a schematic diagram of a high-voltage circuit.

[0043] Figure 6 This is the schematic diagram of the negative high-voltage sampling circuit;

[0044] Figure 7 This is a diagram of a temperature sensor and its peripheral circuitry.

[0045] Figure 8 This is the schematic diagram of the external reference voltage circuit.

[0046] Figure 9 This is a schematic diagram for debugging the serial port circuit. Detailed Implementation

[0047] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

[0048] Example 1

[0049] An automated testing method for gamma sensor plateau curves, see [link to documentation]. Figure 2 The process shown first involves selecting multiple low duty cycle PWM signals for functional self-testing. Here, "low duty cycle" means that the input voltage of the gamma sensor corresponding to the PWM signal does not exceed 1000V; for example, duty cycles of 3%, 6%, and 9% can be selected.

[0050] The controller sequentially outputs PWM signals with duty cycles of 3%, 6%, and 9%. These signals are then converted into high-voltage inputs to the gamma sensor with varying amplitudes. The controller then uploads the gamma pulse counts, gamma sensor input high voltage, and temperature at different low duty cycles to a PC for data verification. If the gamma pulse count is zero, the gamma sensor input high voltage increases with the duty cycle, and the temperature detected by the temperature sensor is close to the set ambient temperature, the data is considered normal.

[0051] After the self-test is successful, the gamma sensor is connected to begin temperature checking. The controller samples the temperature every 5 seconds, and after 20 consecutive measurements of the gamma sensor's operating temperature and the ambient set temperature, if the error does not exceed 2°C, the temperature check is considered successful.

[0052] The ambient temperature is then set, and the test is officially started. The controller accumulates the gamma pulse count value within a unit of time. This unit of time can be set according to requirements, for example, 120 seconds. After each set of gamma pulse count values ​​is collected, the controller uploads the input high voltage and gamma pulse count value to the PC. Then, it continuously increases the duty cycle of the PWM signal (i.e., increases the input high voltage) and repeats the above detection steps until the preset maximum value of the input high voltage has also been tested.

[0053] The input high voltage is fed back to the controller's ADC module via the circuit. The controller monitors the input high voltage and dynamically adjusts the duty cycle of the PWM signal to ensure that the input high voltage remains within the set range. When the input high voltage is adjusted within the range of 1300-1700V, the preset maximum value of the input high voltage is 1700V. When the controller detects that the input high voltage exceeds 1700V, the entire test cycle at the current ambient temperature ends. The environment is then adjusted to other set temperatures, and the above test process is repeated.

[0054] In this embodiment, the high voltage adjustment interval of the input high voltage is 50V, that is, the input high voltage is increased in 50V increments. Since increasing the duty cycle of the PWM signal leads to an increase in the input high voltage, controlling the duty cycle of the PWM signal to increase slowly in fixed units (e.g., 0.1%) allows the input high voltage to increase in fixed units.

[0055] Example 2

[0056] An automated testing system for gamma sensor plateau curves is provided, implementing the automated testing method for gamma sensor plateau curves disclosed in Example 1. The system will be described in detail below according to its functional modules.

[0057] 1. Electrical pulse signal processing circuit: Converts the electrical pulse signal output by the gamma sensor into a square wave signal that can be recognized by the main controller.

[0058] Existing technologies have proposed solutions for electrical pulse signal processing circuits, but considering the high temperature and strong vibration working environment of gamma sensors downhole, this embodiment provides the following preferred solution.

[0059] See Figure 3 By using a precision sampling resistor and a current sensing amplifier, the current pulse signal output by the gamma sensor is converted into a voltage pulse signal. This not only preserves the polarity (negative polarity) of the original signal, facilitating subsequent circuit identification and processing, but also converts the weak current pulse (milliampere level) into a voltage signal (volt level) suitable for ADC sampling. Furthermore, voltage signals have stronger anti-interference capabilities than current signals.

[0060] The current sensing amplifier uses a precisely matched resistor network inside, and the temperature drift cancels each other out; the high common-mode rejection ratio can effectively suppress common-mode interference caused by power supply voltage fluctuations and temperature changes; the temperature drift of the sampling resistor can also be suppressed by the differential input structure of the high-precision amplifier.

[0061] Current sensing amplifiers are available from various brands and models, such as Texas Instruments' INA series. This example selects the INA193 (with an internal fixed gain of 20V / V), see [link to documentation]. Figure 3 The current pulse signal output by the gamma sensor passes through the protection resistor R120 and is then transmitted from the current sensing amplifier V. IN+ Pin input, from V IN- The pin outputs through the protection resistor R47, and the precision sampling resistor is connected to V. IN+ pin and V IN- Between the pins, the OUT pin outputs a voltage pulse signal SIN_OUT. Additionally, V... IN+ pin and V IN- A filter capacitor C5 is connected between the pins. The V+ pin is connected to the +5V power supply and is grounded through a decoupling capacitor C10. The GND pin is grounded.

[0062] When a current pulse signal flows through a precision sampling resistor, a voltage drop is generated across the resistor. For negative current, V IN+ Potential below V IN- The resulting differential voltage is amplified by 20 times by INA193 and then output as a negative polarity voltage pulse signal SIN_OUT.

[0063] The protective resistors R120 and R47 have the following functions:

[0064] 1. Current limiting and electrostatic discharge (ESD) protection: R47 limits the current flowing from the signal source (preamplifier circuit) into the positive input terminal of the amplifier, and R120 limits the current flowing from the signal source into the negative input terminal of the amplifier. When voltage spikes, electrostatic discharge, or accidental short circuits occur at the input terminal, these two resistors can limit the inrush current and protect the fragile input differential pair of INA193 transistors.

[0065] 2. Reduce the impact of input bias current: The input bias current of the INA193 is approximately ±0.5μA (typical value). The voltage drop generated by the 100Ω resistor under the input bias current is only 0.05mV, which has almost no impact on the measurement accuracy. Without this resistor, the parasitic capacitance at the input terminal and external interference may form an unstable operating point.

[0066] 3. Low-pass filter with capacitor C5: R47 and C5 (10μF) form a first-order RC low-pass filter with a cutoff frequency of f_c = 1 / (2πRC) ≈ 1 / (2×3.14×100×10×10⁻ 6(≈160Hz) can effectively filter out high-frequency noise and improve measurement stability.

[0067] See Figure 3 In this embodiment, the precision sampling resistor is composed of two precision resistors R35 and R46 connected in parallel. This is mainly to effectively distribute the power while obtaining an extremely low sampling resistance value, reduce the operating temperature and temperature drift of a single resistor, and improve the long-term reliability and measurement stability of the system in harsh environments such as high temperature.

[0068] Although the negative voltage pulse signal SIN_OUT output by the high-precision amplifier has pulse characteristics (rapid rise, slow fall), it is still an analog voltage waveform and needs to be converted into a digital square wave signal. In this embodiment, a hysteresis comparator is used to convert the analog voltage waveform into a square wave signal for output.

[0069] See Figure 4 A voltage follower is set in the pre-stage of the hysteresis comparator. The high input impedance and low output impedance of the voltage follower are used to buffer and isolate the front and rear stages. This ensures that the high input impedance will not cause a load effect on the high-precision current sensing amplifier in the front stage. At the same time, its low output impedance can stably drive the comparator in the rear stage and prevent signal attenuation.

[0070] Since voltage followers and hysteresis comparators are relatively mature circuit structures, their configurations will not be described in detail here. By setting the upper and lower gate limit voltages VT+ and VT- through the hysteresis comparator, noise and small-amplitude interference in the gamma sensor pulse signal are reduced, while avoiding false triggering and oscillation. This improves the accuracy of the microcontroller in acquiring square wave signals, thereby enhancing the overall reliability of the system.

[0071] II. Main Controller: Outputs a PWM signal with a fixed frequency and a slowly adjusted duty cycle. Simultaneously, it acquires the high voltage input from the gamma sensor, acquires the square wave signal output from the electrical pulse signal processing circuit, and detects the gamma electrical pulse count value per unit time.

[0072] III. High Voltage Circuit: Based on the PWM signal, the external power supply is converted into a dynamically changing gamma sensor input high voltage.

[0073] See Figure 5 The high-voltage circuit includes a PWM drive and power switching unit and a boost unit.

[0074] The PWM driver and power switching unit converts the PWM signal into a switching signal capable of efficiently driving the power transformer. The main controller generates the HV_PWM signal, the duty cycle of which determines the final output voltage level.

[0075] The MCP1416T is a high-speed MOSFET driver that receives 3.3V / 5V logic level PWM signals and outputs a gate drive signal with strong current drive capability (e.g., 2A peak) to turn MOSFET Q1 on and off at extremely fast speeds (nanoscale). The power MOSFET Q1 acts as a high-speed switch, chopping the DC input voltage (VCC, such as 12V or 24V) into a high-frequency square wave under the control of the driver. When Q1 is on, energy is stored in the primary inductance of transformer T1; when Q1 is off, energy is transferred to the secondary winding.

[0076] The boost unit mainly consists of a power transformer and a voltage multiplier circuit, used for electrical isolation and voltage boosting, and outputs high voltage to the gamma sensor input.

[0077] The power transformer T1 is the core of the entire circuit. Its primary winding, along with Q1 and VCC, forms the primary circuit. The secondary winding has far more turns than the primary winding, enabling voltage boosting. When Q1 is on, the secondary diode is reverse-biased and cut off, storing energy in the transformer as a magnetic field. When Q1 is off, the magnetic field energy is released, inducing a high voltage in the secondary winding, causing the diode to conduct and supplying power to the load and capacitor. C30-C34 and D3-D6 form a 4x voltage multiplier circuit, which can boost the peak input voltage by approximately four times, achieving the high input voltage required by the gamma sensor.

[0078] IV. Negative High Voltage Acquisition Circuit: After the high voltage input from the gamma sensor is reversed and reduced, it is sent to the ADC module of the main controller.

[0079] See Figure 6 The output voltage of the high-voltage circuit is inverted and reduced by a factor of 500 after passing through the operational amplifier OPA189IDR, and simultaneously converted into a positive voltage. After RC filtering, it is output as HV_ADC to the main controller's ADC module. When the output voltage of the high-voltage circuit is -1500V, HV_ADC is 3V.

[0080] The main controller dynamically adjusts the duty cycle of the output PWM signal by monitoring the input voltage to ensure that the input high voltage is within the set range.

[0081] V. High-Temperature Chamber: Provides different testing temperatures. In the application scenarios of this invention, it mainly provides two ambient temperatures: 25℃ and 150℃.

[0082] VI. Temperature Sensor: This sensor detects the operating temperature of the gamma sensor and the set temperature of the high-temperature chamber, transmitting the data to the main controller for temperature monitoring. The temperature sensor used is an LM35AH, and its peripheral circuitry is as follows: Figure 7 As shown.

[0083] VII. External Reference Voltage Circuit: Provides a high-precision ADC reference voltage for the system, ensuring the accuracy of input high voltage and temperature detection. The external reference voltage circuit is based on the precision voltage reference chip REF5040IDG4, and its peripheral circuitry is as follows: Figure 8 As shown.

[0084] 8. Debug the serial port circuit, see [link / reference] Figure 9 It connects to the PC and is used to transmit debugging data.

[0085] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

Claims

1. An automated testing method for gamma sensor plateau curves, characterized in that, The controller outputs a PWM signal with a fixed frequency and a slowly adjusted duty cycle. This PWM signal is then converted into a dynamically changing high voltage input to the gamma sensor, providing the operating voltage for the gamma sensor. Simultaneously, the high voltage input is converted into an analog signal that can be recognized by the controller's ADC module. By monitoring the high voltage input, the controller dynamically adjusts the duty cycle of the PWM signal to ensure that the high voltage input remains within the set range. The electrical pulse signal output by the gamma sensor is processed and converted into a square wave signal that the controller can recognize. The controller collects the rising edge of the square wave signal, and each rising edge is recorded as a gamma electrical pulse signal. The gamma electrical pulse signals in a unit time are accumulated to obtain a set of gamma electrical pulse count values. During the test, the required temperature environment is provided, and the operating temperature of the gamma sensor is monitored in real time. The controller collects the gamma pulse count values ​​output by the gamma sensor per unit time under different temperatures and different input high voltages, and summarizes them to obtain the gamma sensor plateau curve.

2. The automated testing method for gamma sensor plateau curves according to claim 1, characterized in that, The duty cycle of the PWM signal increases slowly in units of 0.1%. When the input high voltage monitored by the controller in real time reaches each preset voltage value, the duty cycle of the PWM signal remains unchanged for a certain period of time, which facilitates the accumulation of gamma pulse count values.

3. The automated testing method for gamma sensor plateau curves according to claim 1, characterized in that, The input high voltage can be adjusted within the range of 1300 to 1700V, with a high voltage adjustment interval of 50V.

4. The automated testing method for the gamma sensor plateau curve according to claim 1, characterized in that, Before the test begins, select multiple low duty cycle PWM signals for functional self-test. The input voltage of the gamma sensor corresponding to the low duty cycle PWM signal should not exceed 1000V. Upload the gamma pulse count value, gamma sensor input high voltage, and temperature under different low duty cycles to the PC to verify whether the data is normal. After the function self-test is successful, connect the gamma sensor and start the temperature check. Sample the temperature every few seconds. Collect the working temperature of the gamma sensor and the ambient set temperature N times in a row. After confirming that the error does not exceed the allowable range, start the test and accumulate the gamma pulse count value. After each set of gamma pulse count values ​​is collected, upload the high voltage input of the gamma sensor and the gamma pulse count value to the PC. Continue until the preset maximum value of the high voltage input of the gamma sensor has also been tested. Adjust the ambient temperature setting and repeat the above test process.

5. An automated testing system for gamma sensor plateau curves based on the automated testing method for gamma sensor plateau curves according to any one of claims 1-4, characterized in that, include: The electrical pulse signal processing circuit is used to convert the electrical pulse signal output by the gamma sensor into a square wave signal that can be recognized by the main controller. The main controller is used to output a PWM signal with a fixed frequency and a slowly adjusted duty cycle. At the same time, it acquires the high voltage input from the gamma sensor, acquires the square wave signal output from the electrical pulse signal processing circuit, and detects the gamma electrical pulse count value per unit time. High-voltage circuitry is used to convert external power into dynamically changing gamma sensor input high voltage based on PWM signals. The negative high voltage acquisition circuit is used to reverse and reduce the high voltage input from the gamma sensor and send it to the main controller ADC module. High-temperature chambers are used to provide different test temperatures; Temperature sensor is used to detect the operating temperature of gamma sensor and the set temperature of high temperature chamber, and transmit the data to the main controller; An external reference voltage circuit is used to provide a reference voltage for system operation; The serial port circuit is used for debugging and is connected to the PC for transmitting debugging data.

6. The automated testing system for gamma sensor plateau curves according to claim 5, characterized in that, The electrical pulse signal processing circuit uses a precision sampling resistor and a current sensing amplifier to convert the current pulse signal output by the gamma sensor into a voltage pulse signal. The precision sampling resistor is composed of two precision resistors connected in parallel. The signal is then passed through a voltage follower and a hysteresis comparator to output a square wave signal.

7. The automated testing system for gamma sensor plateau curves according to claim 6, characterized in that, The current pulse signal output by the gamma sensor passes through the protection resistor R120 and is then transmitted to the current sensing amplifier V. IN+ Pin input, from V IN- The pin outputs through the protection resistor R47, and the precision sampling resistor is connected to V. IN+ pin and V IN- Between the pins, the OUT pin outputs a negative polarity voltage pulse signal; V IN+ pin and V IN- A capacitor C5 is connected between the pins.

8. The automated testing system for gamma sensor plateau curves according to claim 5, characterized in that, High-voltage circuits include: The PWM driver and power switching unit is used to convert the PWM signal into a switching signal that can efficiently drive the power transformer. The boost unit mainly consists of a power transformer and a voltage multiplier circuit, used for electrical isolation and voltage boosting, and outputs high voltage to the gamma sensor input.

9. The automated testing system for gamma sensor plateau curves according to claim 1, characterized in that, The negative high voltage acquisition circuit reduces the high voltage input from the gamma sensor in reverse, converts it into a positive voltage, and then outputs it to the main controller ADC module after RC filtering. The main controller monitors the input high voltage and dynamically adjusts the duty cycle of the output PWM signal to ensure that the input high voltage is within the set range.

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