Current source control method for quantum sensor and related device

Abstract

The invention provides a current source control method for a quantum sensor and a related device. The current source control method comprises the steps that a DAC module receives a control signal of an MCU and outputs a set voltage VSET; after the voltage VSET is set to be subjected to low-pass filtering, voltage VSET + is generated and acts on the in-phase end of the operational amplifier; filtering the output voltage Vout of the operational amplifier and outputting voltage V; an instrument amplifier is used for collecting voltage flowing through the two ends of the sampling resistor RSENSE and amplifying the voltage; voltage flowing through the two ends of the sampling resistor RSENSE is subjected to low-pass filtering to generate voltage VSET-, and the voltage VSET-acts on the anti-phase end of the operational amplifier; under the action of the negative feedback network, the output voltage VOUT of the operational amplifier is automatically adjusted until VSET + and VSET-are equal; and filtering the final output current to realize the generation of the output current IXOUT. According to the technical scheme, the technical problems that in the prior art, a current source is large in temperature drift, low in precision, poor in long-term stability, prone to being affected by aging and noise, low in bandwidth, lack of digital programmable capacity and inconvenient to adjust are solved.

Description

Technical Field

[0001] This invention relates to the field of environmental magnetic field compensation technology for quantum sensors, and in particular to a current source control method and related apparatus for quantum sensors. Background Technology

[0002] Quantum sensors have advantages such as high precision and small size. They are mainly used for measuring the Earth's magnetic field, measuring weak magnetic fields in organisms such as brain magnetoencephalography and heart magnetoencephalography, as well as detecting underwater, surface and airborne targets. They are of great significance in national economic development and national defense.

[0003] Environmental magnetic field compensation is a key technical aspect for quantum sensors to achieve high-sensitivity detection and stable operation. Because quantum sensors are extremely sensitive to magnetic fields, the Earth's magnetic field and various artificial interference magnetic fields (such as those from power lines, vehicles, and electronic devices) can far exceed the signal being measured, leading to sensor saturation or a significant drop in the signal-to-noise ratio. Therefore, effective environmental magnetic field compensation is essential to enable them to operate in a near-zero magnetic field environment.

[0004] Active magnetic compensation, which uses feedback control coils to cancel out the ambient magnetic field in real time, is currently the most mainstream method for compensating for ambient magnetic fields. Its basic working process is as follows: ① A triaxial magnetic sensor is used to monitor the ambient magnetic field in real time; a low-precision magnetometer or an auxiliary atomic magnetometer can be used. ② The controller adjusts the coil current according to the sensor input. ③ Three sets of compensation coils generate reverse magnetic fields to cancel out the background field. This solution can dynamically track changes in the magnetic field and is suitable for mobile or semi-open environments. Its cost is lower than that of a fully shielded room, but it has extremely stringent requirements for a high-precision, low-noise, and wide-bandwidth current source.

[0005] Current sources in existing technologies are mostly implemented using operational amplifiers in conjunction with transistors or current mirror structures. Although the structure is simple, it suffers from many problems such as large temperature drift, low accuracy, poor long-term stability, susceptibility to aging and noise, low bandwidth, lack of digital programmability, and inconvenient adjustment, making it difficult to meet the application requirements of quantum sensors. Summary of the Invention

[0006] This invention provides a current source control method and related device for quantum sensors, which can solve the technical problems of large temperature drift, low accuracy, poor long-term stability, susceptibility to aging and noise, low bandwidth, lack of digital programmability, and inconvenient adjustment of current sources in the prior art.

[0007] According to one aspect of the present invention, a current source control method for a quantum sensor is provided, comprising: a high-precision reference voltage source module providing a stable and low-noise reference voltage to a DAC module; the DAC module receiving a control signal from a microcontroller unit (MCU) and outputting a setting voltage V. SET Set voltage VSET After being low-pass filtered by the first low-pass filter, a voltage V is generated. SET+ This is applied to the non-inverting input of the operational amplifier; a second low-pass filter is constructed to filter the output voltage V of the operational amplifier. out The filter is applied and a voltage V is output. The output voltage V flows through the sampling resistor R. SENSE The instrumentation amplifier is used to collect the current flowing through the sampling resistor R. SENSE The voltage across the two ends is amplified; a third low-pass filter is constructed, and the current flows through the sampling resistor R. SENSE The voltage across the two ends, after being low-pass filtered by the third low-pass filter, produces voltage V. SET- This is applied to the inverting input of the operational amplifier; under the influence of the negative feedback network, the output voltage V of the operational amplifier... OUT Automatic adjustment until the voltage V across the operational amplifier is reached. SET+ V SET- Equal; construct a fourth low-pass filter to filter the current flowing through the sampling resistor R. SENSE The final output current at both ends is filtered to reduce noise interference within the signal bandwidth, ultimately achieving the desired output current I. X_OUT The generation of .

[0008] Furthermore, the current source control method for quantum sensors also includes: a temperature sensor collects the internal temperature T of the current source device in real time and generates a compensation curve, which is pre-stored in the microcontroller unit (MCU). The MCU dynamically adjusts the output of the DAC module according to the pre-stored compensation curve to compensate for temperature drift.

[0009] Furthermore, the microcontroller unit (MCU) communicates via SPI or I / O. 2 The C interface receives external commands and supports current setting, range switching, self-calibration, fault detection, and status feedback.

[0010] Furthermore, the sampling resistor R SENSE Low temperature coefficient metal foil resistors using four-terminal connection have a resistance temperature coefficient of less than 0.05ppm / ℃ and a power coefficient of less than 5ppm / mW.

[0011] Furthermore, the DAC is a 24-bit high-resolution serial DAC with a minimum step voltage of less than 1μV and an integral nonlinearity better than ±2LSB.

[0012] Furthermore, the high-precision reference voltage source adopts a low-temperature drift bandgap reference source with a temperature coefficient of less than 1ppm / ℃ and long-term stability better than 5ppm / year.

[0013] According to another aspect of the present invention, a current source device for a quantum sensor is provided, which is used to implement the current source control method for a quantum sensor as described above.

[0014] Furthermore, the current source device for the quantum sensor includes a high-precision reference voltage source module, a DAC module, a microcontroller unit (MCU), an operational amplifier, a current sensing sampling resistor, a temperature compensation and calibration module, an instrumentation amplifier, a first low-pass filter, a second low-pass filter, a third low-pass filter, and a fourth low-pass filter. The high-precision reference voltage source module and the MCU are respectively connected to the DAC module. The DAC module, the first low-pass filter, the non-inverting input of the operational amplifier, the second low-pass filter, the current sensing sampling resistor, the instrumentation amplifier, the third low-pass filter, and the inverting input of the operational amplifier are connected in sequence. The fourth low-pass filter is connected to the current sensing sampling resistor. The system includes a high-precision reference voltage source module to provide a stable and low-noise reference voltage; a DAC module to receive external control signals and output an adjustable voltage; an operational amplifier, a second low-pass filter, a current-sensing sampling resistor, an instrumentation amplifier, and a third low-pass filter forming a negative feedback control loop; a current-sensing sampling resistor to convert voltage signals into current signals; a temperature compensation and calibration module to monitor temperature in real time and compensate for current drift; a microcontroller unit (MCU) to implement digital control, parameter configuration, automatic calibration, and communication interfaces; and first, second, third, and fourth low-pass filters for bandwidth control and noise suppression of the output current.

[0015] Furthermore, the temperature compensation and calibration module includes a temperature sensor and a non-volatile memory. The temperature sensor is used to acquire the internal temperature of the current source device in real time, and the non-volatile memory is used to store the temperature-current compensation curve and perform real-time calibration under the control of the microcontroller unit (MCU).

[0016] According to another aspect of the invention, a quantum sensor is provided, which includes a current source device for a quantum sensor as described above.

[0017] By applying the technical solution of this invention, a current source control method for quantum sensors is provided. This method provides a stable and low-noise reference voltage through a high-precision reference voltage source module, and sets the voltage V... SET After being low-pass filtered by the first low-pass filter, a voltage V is generated. SET+ It acts on the non-inverting input of the operational amplifier and flows through the sampling resistor R. SENSE The voltage across the two ends, after being low-pass filtered by the third low-pass filter, produces voltage V. SET- And it acts on the inverting input of the operational amplifier. Under the action of the negative feedback network, the output voltage V of the operational amplifier... OUT Automatic adjustment until the voltage V across the operational amplifier is reached. SET+ V SET- Equal, the fourth low-pass filter affects the flow through the sampling resistor RSENSE The final output current at both ends is filtered to reduce noise interference within the signal bandwidth, ultimately achieving the desired output current I. X_OUT Therefore, compared with the prior art, the current source control method for quantum sensors provided by this invention has high output current accuracy; good temperature stability, with automatic temperature compensation and self-calibration functions; low output noise, suitable for high-sensitivity measurement systems; and dynamically adjustable output with wideband response. Attached Figure Description

[0018] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0019] Figure 1 A schematic diagram of the overall structure of a current source device for a quantum sensor according to a specific embodiment of the present invention is shown;

[0020] Figure 2 A schematic diagram of environmental magnetic field compensation for a quantum sensor according to a specific embodiment of the present invention is shown.

[0021] The above figures include the following reference numerals:

[0022] 10. High-precision reference voltage source module; 20. DAC module; 30. Microcontroller unit (MCU); 40. Operational amplifier; 50. Current sensing sampling resistor; 60. Instrumentation amplifier; 70. First low-pass filter; 80. Second low-pass filter; 90. Third low-pass filter; 100. Fourth low-pass filter; 110. Temperature sensor. Detailed Implementation

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0026] like Figure 1 As shown, a current source control method for a quantum sensor is provided according to a specific embodiment of the present invention. The method includes: a high-precision reference voltage source module 10 providing a stable and low-noise reference voltage to a DAC module 20; and the DAC module 20 receiving control signals from a microcontroller unit MCU 30 and outputting a setting voltage V. SET Set voltage V SET After being low-pass filtered by the first low-pass filter 70, a voltage V is generated. SET+ And act on the non-inverting input of operational amplifier 40; construct a second low-pass filter 80, which affects the output voltage V of operational amplifier 40. out The filter is applied and a voltage V is output. The output voltage V flows through the sampling resistor R. SENSE The instrumentation amplifier 60 is used to collect the current flowing through the sampling resistor R. SENSE The voltage across the two ends is amplified; a third low-pass filter 90 is constructed, and the current flows through the sampling resistor R. SENSE The voltage across the two ends, after being filtered by the third low-pass filter (90°), produces voltage V. SET- And it acts on the inverting input of operational amplifier 40; under the action of the negative feedback network, the output voltage V of operational amplifier 40... OUT Automatic adjustment until the voltage V across operational amplifier 40 is reached. SET+ V SET-Equal; Construct a fourth low-pass filter 100 to filter the current flowing through the sampling resistor R. SENSE The final output current at both ends is filtered to reduce noise interference within the signal bandwidth, ultimately achieving the desired output current I. X_OUT The generation of .

[0027] This configuration provides a current source control method for quantum sensors. This method utilizes a high-precision reference voltage source module to provide a stable and low-noise reference voltage, setting the voltage V... SET After being low-pass filtered by the first low-pass filter, a voltage V is generated. SET+ It acts on the non-inverting input of the operational amplifier and flows through the sampling resistor R. SENSE The voltage across the two ends, after being low-pass filtered by the third low-pass filter, produces voltage V. SET- And it acts on the inverting input of the operational amplifier. Under the action of the negative feedback network, the output voltage V of the operational amplifier... OUT Automatic adjustment until the voltage V across the operational amplifier is reached. SET+ V SET- Equal, the fourth low-pass filter affects the flow through the sampling resistor R SENSE The final output current at both ends is filtered to reduce noise interference within the signal bandwidth, ultimately achieving the desired output current I. X_OUT Therefore, compared with the prior art, the current source control method for quantum sensors provided by this invention has high output current accuracy; good temperature stability, with automatic temperature compensation and self-calibration functions; low output noise, suitable for high-sensitivity measurement systems; and dynamically adjustable output with wideband response.

[0028] Furthermore, in this invention, the current source control method for quantum sensors further includes: the temperature sensor 110 collects the internal temperature T of the current source device in real time and generates a compensation curve, which is pre-stored in the microcontroller unit MCU30. The microcontroller unit MCU30 dynamically adjusts the output of the DAC module 20 according to the pre-stored compensation curve to compensate for temperature drift.

[0029] Specifically, in this invention, the microcontroller unit MCU30 communicates via SPI or I / O. 2 The C interface receives external commands and supports current setting, range switching, self-calibration, fault detection, and status feedback.

[0030] Sampling resistor R SENSEThe system employs low-temperature-coefficient metal foil resistors with a four-terminal connection, exhibiting a resistance temperature coefficient of less than 0.05 ppm / ℃ and a power factor of less than 5 ppm / mW. The DAC is a 24-bit high-resolution serial DAC with a minimum step voltage of less than 1 μV and an integral nonlinearity (INL) better than ±2 LSB. The high-precision reference voltage source utilizes a low-temperature-drift bandgap reference source with a temperature coefficient of less than 1 ppm / ℃ and long-term stability better than 5 ppm / year.

[0031] According to another aspect of the present invention, a current source device for a quantum sensor is provided, which is used to implement the current source control method for a quantum sensor as described above. The current source device for the quantum sensor includes a high-precision reference voltage source module 10, a DAC module 20, a microcontroller unit (MCU) 30, an operational amplifier 40, a current sensing sampling resistor 50, a temperature compensation and calibration module, an instrumentation amplifier 60, a first low-pass filter 70, a second low-pass filter 80, a third low-pass filter 90, and a fourth low-pass filter 100. The high-precision reference voltage source module 10 and the microcontroller unit (MCU) 30 are respectively connected to the DAC module 20. The DAC module 20, the first low-pass filter 70, the non-inverting input of the operational amplifier 40, the second low-pass filter 80, the current sensing sampling resistor 50, the instrumentation amplifier 60, the third low-pass filter 90, and the inverting input of the operational amplifier 40 are all connected. The terminals are connected in sequence. The fourth low-pass filter 100 is connected to the current sensing sampling resistor 50. The high-precision reference voltage source module 10 is used to provide a stable and low-noise reference voltage. The DAC module 20 is used to receive external control signals and output an adjustable voltage. The operational amplifier 40 forms a negative feedback control loop. The current sensing sampling resistor 50 is used to convert the voltage signal into a current signal. The temperature compensation and calibration module is used to monitor the temperature in real time and compensate for current drift. The microcontroller unit MCU 30 is used to realize digital control, parameter configuration, automatic calibration and communication interface. The first low-pass filter 70, the second low-pass filter 80, the third low-pass filter 90 and the fourth low-pass filter 100 are all used for bandwidth control and noise suppression of the output current.

[0032] Furthermore, in this invention, the temperature compensation and calibration module includes a temperature sensor 110 and a non-volatile memory. The temperature sensor 110 is used to collect the internal temperature of the current source device in real time, and the non-volatile memory is used to store the temperature-current compensation curve and perform real-time calibration under the control of the microcontroller unit MCU30.

[0033] According to another aspect of the invention, a quantum sensor is provided, which includes a current source device for a quantum sensor as described above.

[0034] This configuration provides a quantum sensor that includes the current source device for quantum sensors described above. The current source device provided by this invention offers advantages such as high output current accuracy, good temperature stability with automatic temperature compensation and self-calibration functions, low output noise (making it suitable for high-sensitivity measurement systems), and dynamically adjustable output with a wide bandwidth response. Therefore, its application in quantum sensors can significantly improve the performance of the quantum sensors.

[0035] To gain a further understanding of the present invention, the following description is provided in conjunction with... Figure 1 and Figure 2 The current source control method for quantum sensors provided by this invention will be described in detail.

[0036] The purpose of this invention is to provide a high-precision, low-noise, wide-bandwidth current source device and its control method, which can achieve high-precision, low-noise, wide-bandwidth current output within a range of 100 milliamperes, and has good temperature stability and digital programmable adjustment capability.

[0037] This invention proposes a high-precision, low-noise, wide-bandwidth current source device, including the construction of the hardware system and the implementation of the software algorithm.

[0038] The technical solution of this invention:

[0039] A high-precision, low-noise, wide-bandwidth current source device, comprising at least current generation and compensation correction:

[0040] The current source device for quantum sensors includes a high-precision reference voltage source module 10, a DAC module 20, a microcontroller unit (MCU) 30, a high-gain, low-temperature-drift operational amplifier 40, a current-sensing sampling resistor 50, a temperature compensation and calibration module, an instrumentation amplifier 60, a first low-pass filter 70, a second low-pass filter 80, a third low-pass filter 90, and a fourth low-pass filter 100. The high-precision reference voltage source module 10 and the microcontroller unit (MCU) 30 are respectively connected to the DAC module 20. The DAC module 20, the first low-pass filter 70, the non-inverting input of the operational amplifier 40, the second low-pass filter 80, the current-sensing sampling resistor 50, the instrumentation amplifier 60, the third low-pass filter 90, and the operational amplifier 40 are all connected to the DAC module 20. The inverting inputs of the 0 are connected in sequence. The fourth low-pass filter 100 is connected to the current sensing sampling resistor 50. The high-precision reference voltage source module 10 is used to provide a stable and low-noise reference voltage. The DAC module 20 is used to receive external control signals and output an adjustable voltage. The operational amplifier 40 forms a negative feedback control loop. The current sensing sampling resistor 50 is used to convert the voltage signal into a current signal. The temperature compensation and calibration module is used to monitor the temperature in real time and compensate for current drift. The microcontroller unit MCU 30 is used to realize digital control, parameter configuration, automatic calibration and communication interface. The first low-pass filter 70, the second low-pass filter 80, the third low-pass filter 90 and the fourth low-pass filter 100 are all used for bandwidth control and noise suppression of the output current.

[0041] (1) Generation of electric current:

[0042] ① Setting the voltage generation:

[0043] The formula for calculating the voltage is as follows:

[0044] V SET =I X ×R SENSE (1)

[0045] Among them, V SET R is the DAC output voltage. SENSE For the sampling resistor, I X This represents the desired output current.

[0046] Through real-time wideband DAC dynamic control by MCU, and after low-pass filtering, voltage V is generated. SET+ It acts on the non-inverting input of the operational amplifier.

[0047] V SET+ =LPF(V SET (2)

[0048] LPF is a general-purpose low-pass filter, which will not be discussed in this patent.

[0049] The MCU communicates via SPI or I 2 The C interface receives external commands and supports current setting, range switching, self-calibration, fault detection, and status feedback.

[0050] The high-precision reference voltage source adopts a low-temperature drift bandgap reference source (such as LTZ1000 or similar devices), with a temperature coefficient of less than 1ppm / ℃ and long-term stability better than 5ppm / year.

[0051] The DAC is a 24-bit high-resolution serial DAC with a minimum step voltage of less than 1μV and an integral nonlinearity (INL) better than ±2LSB.

[0052] The precision sampling resistor is a low temperature coefficient metal foil resistor (such as the Vishay Z-Foil series) connected by a four-terminal method, with a resistance temperature coefficient of less than 0.05ppm / ℃ and a power coefficient of less than 5ppm / mW.

[0053] ② Acquisition of feedback voltage:

[0054] The instrumentation amplifier is used to collect the current flowing through the sampling resistor R. SENSE The voltage at both ends is amplified:

[0055] V SENSE =I X_S ×R SENSE (3)

[0056] Among them, V SENSE For the flow through the sampling resistor R SENSE The voltage across the terminals, R SENSE For the sampling resistor, I X_S This represents the actual output current.

[0057] Flow through sampling resistor R SENSE The voltage across the two ends, after being low-pass filtered, produces voltage V. SET- It acts on the inverting input of the operational amplifier.

[0058] V SET- =LPF(V SENSE (4)

[0059] The instrumentation amplifier is a low-noise, wide-bandwidth amplifier, such as the AD8138.

[0060] ③ Negative feedback network control

[0061] Under the influence of the negative feedback network, the output voltage V of the operational amplifier OUT Automatic adjustment until the voltage V across the operational amplifier is reached. SET+ V SET- equal.

[0062] VOUT =Φ(V SET+ V SET- A) (5)

[0063] Where A is the open-loop gain of the operational amplifier, Φ(V SET+ V SET- A) is a function related to the voltages at the two input terminals of the operational amplifier and the open-loop gain.

[0064] The operational amplifier is a low-noise, high-output amplifier, such as the OPA1622.

[0065] ④ Output voltage filtering

[0066] Construct a low-pass filter to filter the output voltage of the operational amplifier, reducing noise interference within the signal bandwidth:

[0067] V = LPF(V OUT (6)

[0068] ⑦ Construct a low-pass filter to filter the final output current and reduce noise interference within the signal bandwidth:

[0069] I X_OUT =LPF(I X_S (7)

[0070] Through the above process, the output current I is finally achieved. X_OUT The generation of .

[0071] (2) Temperature compensation

[0072] Because the parameters of analog devices exhibit temperature drift, temperature compensation is required for the final output.

[0073] The temperature sensor collects the internal temperature T of the device in real time and generates a compensation curve, which is pre-stored in the MCU. The MCU dynamically adjusts the DAC output according to the pre-stored compensation curve to compensate for temperature drift.

[0074] I T =Φ(I OUT ,T) (8)

[0075] Among them, I T It is the compensated current output, Φ(I) OUT ,T) is the compensation function for current output and temperature.

[0076] The temperature compensation and calibration module includes a high-precision temperature sensor (such as PT1000 or digital temperature sensor ADT7420) and a non-volatile memory for storing temperature-current compensation curves and performing real-time calibration under MCU control.

[0077] The advantages of this system compared to existing technologies are:

[0078] It features high output current accuracy, good temperature stability with automatic temperature compensation and self-calibration functions, low output noise, making it suitable for high-sensitivity measurement systems, and dynamically adjustable output with a wide bandwidth response.

[0079] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0080] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0081] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A current source control method for quantum sensors, characterized in that, The current source control method for quantum sensors includes: The high-precision reference voltage source module (10) provides a stable and low-noise reference voltage to the DAC module (20); The DAC module (20) receives the control signal from the microcontroller unit (MCU) (30) and outputs the setting voltage V. SET ; Set voltage V SET After being low-pass filtered by the first low-pass filter (70), a voltage V is generated. SET+ , and act on the non-inverting input of the operational amplifier (40); Construct a second low-pass filter (80) to filter the output voltage V of the operational amplifier (40). out The filter is applied and a voltage V is output. The output voltage V flows through the sampling resistor R. SENSE ; The instrumentation amplifier (60) is used to collect the current flowing through the sampling resistor R. SENSE The voltage at both ends is amplified; Construct a third low-pass filter (90), through which the sampler resistor R flows. SENSE The voltage across the two ends, after being low-pass filtered by the third low-pass filter (90), generates voltage V. SET- , and act on the inverting input of the operational amplifier (40); Under the action of the negative feedback network, the output voltage V of the operational amplifier (40) OUT Automatic adjustment until the voltage V across the operational amplifier (40) is reached. SET+ V SET- equal; Construct a fourth low-pass filter (100) to filter the current flowing through the sampling resistor R. SENSE The final output current at both ends is filtered to reduce noise interference within the signal bandwidth, ultimately achieving the desired output current I. X_OUT The generation of .

2. The current source control method for quantum sensors according to claim 1, characterized in that, The current source control method for quantum sensors further includes: a temperature sensor (110) collects the internal temperature T of the current source device in real time and generates a compensation curve, which is pre-stored in the microcontroller unit (MCU) (30). The microcontroller unit (MCU) (30) dynamically adjusts the output of the DAC module (20) according to the pre-stored compensation curve to compensate for temperature drift.

3. The current source control method for quantum sensors according to claim 1, characterized in that, The microcontroller unit (MCU) (30) communicates via SPI or I / O. 2 The C interface receives external commands and supports current setting, range switching, self-calibration, fault detection, and status feedback.

4. The current source control method for a quantum sensor according to any one of claims 1 to 3, characterized in that, The sampling resistor R SENSE Low temperature coefficient metal foil resistors using four-terminal connection have a resistance temperature coefficient of less than 0.05ppm / ℃ and a power coefficient of less than 5ppm / mW.

5. The current source control method for quantum sensors according to claim 4, characterized in that, The DAC is a 24-bit high-resolution serial DAC with a minimum step voltage of less than 1μV and an integral nonlinearity (INL) better than ±2LSB.

6. The current source control method for quantum sensors according to claim 5, characterized in that, The high-precision reference voltage source adopts a low-temperature drift bandgap reference source with a temperature coefficient of less than 1ppm / ℃ and long-term stability better than 5ppm / year.

7. A current source device for a quantum sensor, characterized in that, The current source device for the quantum sensor is used to implement the current source control method for the quantum sensor as described in claims 1 to 6.

8. The current source device for a quantum sensor according to claim 7, characterized in that, The current source device for the quantum sensor includes a high-precision reference voltage source module (10), a DAC module (20), a microcontroller unit (MCU) (30), an operational amplifier (40), a current sensing sampling resistor (50), a temperature compensation and calibration module, an instrumentation amplifier (60), a first low-pass filter (70), a second low-pass filter (80), a third low-pass filter (90), and a fourth low-pass filter (100). The high-precision reference voltage source module (10) and the microcontroller unit (MCU) (30) are respectively connected to the DAC module (20). The DAC module (20), the first low-pass filter (70), the non-inverting input of the operational amplifier (40), the second low-pass filter (80), the current sensing sampling resistor (50), the instrumentation amplifier (60), the third low-pass filter (90), and the inverting input of the operational amplifier (40) are connected in sequence. The fourth low-pass filter (100) is connected in sequence. The high-precision reference voltage source module (10) is connected to the current sensing sampling resistor (50) and is used to provide a stable and low-noise reference voltage; the DAC module (20) is used to receive external control signals and output adjustable voltage; the operational amplifier (40), the second low-pass filter (80), the current sensing sampling resistor (50), the instrumentation amplifier (60), and the third low-pass filter (90) constitute a negative feedback control loop; the current sensing sampling resistor (50) is used to convert the voltage signal into a current signal; the temperature compensation and calibration module is used to monitor the temperature in real time and compensate for current drift; the microcontroller unit (MCU) (30) is used to realize digital control, parameter configuration, automatic calibration, and communication interface; the first low-pass filter (70), the second low-pass filter (80), the third low-pass filter (90), and the fourth low-pass filter (100) are all used for bandwidth control and noise suppression of the output current.

9. The current source device for a quantum sensor according to claim 8, characterized in that, The temperature compensation and calibration module includes a temperature sensor (110) and a non-volatile memory. The temperature sensor (110) is used to collect the internal temperature of the current source device in real time, and the non-volatile memory is used to store the temperature-current compensation curve and perform real-time calibration under the control of the microcontroller unit MCU (30).

10. A quantum sensor, characterized in that, The quantum sensor includes a current source device for a quantum sensor as described in claims 7 to 9.

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