Self-adaptive current detection circuit

Abstract

The utility model discloses a self-adaptive current detection circuit, which is characterized in that a current-voltage conversion circuit connects a Hall current sensor in series to an input original voltage line, collects a current signal for conversion, and outputs a converted voltage; the primary voltage conditioning circuit is used for conditioning the voltage signal after current conversion based on the first group of rail-to-rail operational amplifiers; the secondary voltage conditioning circuit is used for conditioning the voltage signal after current conversion based on a second group of rail-to-rail operational amplifiers, and the amplification factor of the primary voltage conditioning circuit is greater than that of the secondary voltage conditioning circuit; the AD conversion circuit is used for sampling the two conditioned voltage signals respectively, two current values are obtained through software conversion, and a final detection current value is obtained after the two current values are compared with a preset threshold value; according to the invention, the technical problem that the existing measurement technology cannot guarantee high measurement precision under the condition of a large measurement range is solved.

Description

Technical Field

[0001] This application relates to the field of current detection, and more particularly to an adaptive current detection circuit and detection device. Background Technology

[0002] Current detection circuits are widely used in various fields. Besides measuring equipment that needs to test current, almost every device incorporates a current detection circuit for its own safety. Non-measuring devices generally don't require high current accuracy, so their current detection circuits are relatively simple. However, measuring equipment typically has higher requirements for current measurement accuracy and range. How to maintain high measurement accuracy while ensuring a large measurement range is a crucial criterion for evaluating the performance of measuring equipment. A common current measuring device is the multimeter, which uses two settings to measure small and large currents respectively. When measuring small currents with large fluctuations, this setting can easily burn out, causing a short circuit or open circuit. Summary of the Invention

[0003] The main objective of this application is to provide an adaptive current detection circuit and a measuring device. The adaptive current detection circuit aims to solve the technical problem of how to ensure high measurement accuracy under conditions of a large measurement range.

[0004] To achieve the above objectives, the first aspect of this application provides an adaptive current detection circuit, comprising:

[0005] Current-to-voltage conversion circuit, first-stage voltage conditioning circuit, second-stage voltage conditioning circuit, and AD conversion circuit;

[0006] The output of the current-to-voltage conversion circuit is connected to the input of the first-stage voltage conditioning circuit and the input of the second-stage voltage conditioning circuit, respectively. The output of the first-stage voltage conditioning circuit and the output of the second-stage voltage conditioning circuit are connected to the two inputs of the AD conversion circuit, respectively.

[0007] The current-to-voltage conversion circuit is used to acquire voltage signals based on a Hall current sensor.

[0008] The first-level voltage conditioning circuit is used to condition the voltage signal based on the first set of rail-to-rail operational amplifiers to obtain the first voltage signal;

[0009] The secondary voltage conditioning circuit is used to condition the voltage signal based on the second set of rail-to-rail operational amplifiers to obtain a second voltage signal, wherein the amplification factor of the primary voltage conditioning circuit is greater than that of the secondary voltage conditioning circuit.

[0010] The AD conversion circuit is used to sample the first voltage signal to obtain a first sampling signal, and to sample the second voltage signal to obtain a second sampling signal. The converted first sampling signal and the converted second sampling signal are compared with a preset current threshold to obtain the detection current value.

[0011] Optionally, the adaptive current detection circuit includes:

[0012] Hall effect current sensor, capacitors C4, C8, C3, C9 and C10;

[0013] Among them, the first end of capacitor C4 is connected to the original power supply ground terminal G, and the second end is connected to the IP+ pin of the Hall current sensor and the original power supply input terminal V28.

[0014] The first end of capacitor C8 is connected to the IP+ pin of the Hall current sensor and the output of the original power input V28, and the second end is connected to the IP- pin of the Hall current sensor.

[0015] The first end of capacitor C3 is connected to the VCC pin of the Hall current sensor and the output of power supply V5, and the second end is connected to digital ground GND.

[0016] The first end of capacitor C10 is connected to the NC pin of the Hall current sensor, and the second end is grounded (GND).

[0017] The first end of capacitor C9 is connected to the V1OUT pin of the Hall current sensor, and the second end is connected to ground GND and the GND pin of the Hall current sensor.

[0018] Optionally, the adaptive current detection circuit, the first-stage voltage conditioning circuit includes:

[0019] The first rail-to-rail operational amplifier, the second rail-to-rail operational amplifier, resistors R1 to R7, capacitors C1, C2, C5, C6, C7, and Zener diode V1;

[0020] Among them, the first end of resistor R1 is connected to the reference voltage Vref, and the second end is connected to the first end of resistor R2 and the inverting input of the first rail-to-rail operational amplifier.

[0021] The second end of resistor R2 is connected to the first end of resistor R3, and the second end of resistor R3 is connected to the output terminal of the first rail-to-rail operational amplifier.

[0022] The first terminal of capacitor C2 is connected to the reference voltage Vref, and the second terminal is grounded (GND).

[0023] The first terminal of capacitor C1 is connected to the in-phase supply voltage V5 of the first rail-to-rail operational amplifier, and the second terminal is grounded to GND.

[0024] The non-inverting input of the first rail-to-rail operational amplifier is connected to the VCC pin of the Hall current sensor through resistor R7.

[0025] The non-inverting input of the second rail-to-rail operational amplifier is connected to the first terminal of resistor R6, and the second terminal of resistor R6 is grounded to GND.

[0026] The first end of resistor R4 is connected to the output of the second rail-to-rail operational amplifier, and the second end is connected to the first input of the AD conversion circuit.

[0027] The first terminal of capacitor C7 is connected to the non-inverting input terminal of the second rail-to-rail operational amplifier, and the second terminal is grounded to GND.

[0028] The cathode of Zener diode V1 is connected to the non-inverting input terminal of the second rail-to-rail operational amplifier, and the second terminal is grounded to GND.

[0029] The first terminal of capacitor C5 is connected to the second terminal of the fourth resistor R4, and the second terminal is grounded to GND.

[0030] The first terminal of capacitor C6 is connected to the second terminal of the fourth resistor R4, and the second terminal is grounded to GND.

[0031] Optionally, the secondary voltage conditioning circuit includes:

[0032] Third rail-to-rail op-amp, fourth rail-to-rail op-amp, resistors R8 to R9, capacitor C12, capacitor C11

[0033] Resistor R8 has its first terminal connected to the reference voltage Vref, its second terminal connected to the first terminal of resistor R9, and its third terminal connected to the inverting input of the rail-to-rail op-amp.

[0034] Resistor R9, the second end of which is connected to the first end of resistor R10, and the second end of resistor R10 is connected to the output terminal of the third rail-to-rail operational amplifier;

[0035] Capacitor C12 has its first terminal connected to the reference voltage Vref, and its second terminal grounded to GND.

[0036] Capacitor C11, the first terminal is connected to the in-phase supply voltage V5 of the third rail-to-rail operational amplifier, and the second terminal is grounded GND;

[0037] The third rail-to-rail operational amplifier has its non-inverting input connected to the VCC pin of the Hall current sensor via resistor R13.

[0038] Resistor R11 has its first end connected to the output of the fourth rail-to-rail operational amplifier and its second end connected to the second input of the AD conversion circuit.

[0039] Resistor R14, the first end is connected to the second end of resistor R13, and the second end is grounded (GND);

[0040] Resistor R12, the first end is connected to the output of the third rail-to-rail operational amplifier, and the second end is connected to the non-inverting input of the fourth rail-to-rail operational amplifier;

[0041] Capacitor C15, the first end is connected to the non-inverting input of the fourth rail-to-rail op-amp, and the second end is grounded to GND;

[0042] Zener diode V2, cathode connected to the non-inverting input terminal of the fourth rail-to-rail operational amplifier, second terminal grounded to GND;

[0043] Capacitor C13 has its first end connected to the second end of the fourth resistor R11, and both ends of the second end are grounded (GND).

[0044] The first end of capacitor C14 is connected to the second end of the fourth resistor R11, and the second end of each capacitor is grounded (GND).

[0045] Capacitor C16 has its first end connected to resistor R13 and the V1OUT terminal of the Hall current sensor and resistor R13, and its second end connected to the second end of resistor R14 and ground GND.

[0046] Optionally, the adaptive current detection circuit, the AD conversion circuit includes:

[0047] The MCU has a 12-bit AD converter, and the AD converter performs data transmission and storage via DMA.

[0048] To address the aforementioned technical problems, a second aspect of this application also provides a detection device having the adaptive current detection circuit described in the first aspect.

[0049] This application proposes an adaptive current detection circuit and measuring device, comprising a current-to-voltage conversion circuit, a first-stage voltage conditioning circuit, a second-stage voltage conditioning circuit, and an AD conversion circuit. The output of the current-to-voltage conversion circuit is connected to the input of the first-stage voltage conditioning circuit and the input of the second-stage voltage conditioning circuit, respectively, and the outputs of the first-stage and second-stage voltage conditioning circuits are connected to the two inputs of the AD conversion circuit, respectively. The current-to-voltage conversion circuit is used to acquire a voltage signal based on a Hall current sensor. The first-stage voltage conditioning circuit is used to condition the voltage signal based on a first set of rail-to-rail operational amplifiers to obtain a first voltage signal. The second-stage voltage conditioning circuit is used to condition the voltage signal based on a second set of rail-to-rail operational amplifiers to obtain a second voltage signal. The amplification factor of the first-stage voltage conditioning circuit is greater than that of the second-stage voltage conditioning circuit. The AD conversion circuit is used to sample the first voltage signal to obtain a first sampled signal, and to sample the second voltage signal to obtain a second sampled signal. The first and second sampled signals, after conversion, are compared with a preset current threshold to obtain the detected current value. This application uses a Hall current sensor, which isolates the measured current from the detection circuit, preventing interference from the measured current from affecting the detection circuit. Using a rail-to-rail operational amplifier, the signal output from the current-to-voltage conversion circuit is conditioned and isolated before being sent to the AD conversion circuit for processing. The use of a two-stage voltage conditioning circuit—one for small current detection and one for large current detection—with a higher amplification factor than the second stage, allows for adaptive current detection. This improves the detection accuracy for small currents while adapting to the needs of large current detection. The outputs of the two voltage conditioning circuits are connected to the AD conversion circuit to obtain the optimal current detection value, thus solving the technical problem in existing measurement technologies where high measurement accuracy cannot be guaranteed within a large measurement range. Attached Figure Description

[0050] Figure 1 This is a circuit diagram provided for one embodiment of the adaptive current detection circuit of this application.

[0051] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0052] In the diagram: V28, raw power input; Vout, load power input; Vref, reference voltage for the first-stage voltage conditioning circuit, the second-stage voltage conditioning circuit, and the AD conversion circuit; V5, Hall current sensor, supply voltage for the first rail-to-rail op-amp to the fourth rail-to-rail op-amp; V3.3, supply voltage for the microprocessor (MCU); G, ground for the raw power supply and the load power supply; GND, ground for the current detection circuit; Vio, output of the current-to-voltage conversion circuit; AD1, output of the first-stage voltage conditioning circuit; AD2, output of the second-stage voltage conditioning circuit; N1A, second rail-to-rail op-amp; N1B, first rail-to-rail op-amp; N3B, first rail-to-rail op-amp; N3A, second rail-to-rail op-amp; N2, Hall current sensor; MCU, microprocessor; R1-R14, resistors; C1-C16, capacitors; V1 and V2, Zener diodes. Detailed Implementation

[0053] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0054] Reference Figure 1 The adaptive current detection circuit provided in the first embodiment of this application may include: a current-to-voltage conversion circuit 10, a first-stage voltage conditioning circuit 20, a second-stage voltage conditioning circuit 30, and an AD conversion circuit 40; the output of the current-to-voltage conversion circuit 10 is connected to the input of the first-stage voltage conditioning circuit 20 and the input of the second-stage voltage conditioning circuit 30, respectively, and the outputs of the first-stage voltage conditioning circuit 20 and the second-stage voltage conditioning circuit 30 are connected to the two inputs of the AD conversion circuit 40, respectively; wherein, the current-to-voltage conversion circuit 10 is used to acquire voltage signals based on a Hall current sensor; the first-stage voltage conditioning circuit... Circuit 20 is used to condition the voltage signal based on the first set of rail-to-rail operational amplifiers to obtain a first voltage signal; the second-stage voltage conditioning circuit 30 is used to condition the voltage signal based on the second set of rail-to-rail operational amplifiers to obtain a second voltage signal, wherein the amplification factor of the first-stage voltage conditioning circuit 20 is greater than the amplification factor of the second-stage voltage conditioning circuit 30; the AD conversion circuit 40 is used to sample the first voltage signal to obtain a first sampled signal, and to sample the second voltage signal to obtain a second sampled signal, and to compare the converted first sampled signal and the converted second sampled signal with a preset current threshold to obtain a detected current value.

[0055] This application utilizes a Hall effect current sensor to isolate the measured current from the detection circuit, preventing interference from the measured current from affecting the detection circuit. By employing a rail-to-rail operational amplifier, the signal output from the current-to-voltage conversion circuit 10 is conditioned and isolated before being sent to the AD conversion circuit 40 for processing. The use of a two-stage voltage conditioning circuit—a first-stage circuit 20 for small current detection and a second-stage circuit 30 for large current detection—allows for adaptive current detection. The amplification factor of the first-stage circuit 20 is greater than that of the second-stage circuit 30, improving the accuracy of small current detection while adapting to the demands of large current detection. The outputs of the two voltage conditioning circuits are connected to different inputs of the 12-bit AD converter integrated into the microprocessor MCU to obtain the optimal current detection value.

[0056] In one embodiment of this application, the adaptive current detection circuit includes: a Hall current sensor, and capacitors C4, C8, C3, C9, and C10. The first terminal of capacitor C4 is connected to the input power ground G, and the second terminal is connected to the IP+ pin of the Hall current sensor and the input power V28. The first terminal of capacitor C8 is connected to the IP+ pin of the Hall current sensor and the output terminal of the input power V28, and the second terminal is connected to the IP- pin of the Hall current sensor. The first terminal of capacitor C3 is connected to the VCC pin of the Hall current sensor and the output of power supply V5, and the second terminal is connected to digital ground GND. The first terminal of capacitor C10 is connected to the NC pin of the Hall current sensor, and the second terminal is connected to ground GND. The first terminal of capacitor C9 is connected to the V1OUT pin of the Hall current sensor, and the second terminal is connected to ground GND and the GND pin of the Hall current sensor. The current-voltage conversion circuit 10 is a circuit composed of a precision Hall current sensor N2 and capacitors C3, C4, C8, and C10. Capacitor C3 provides power decoupling for Hall current sensor N2 and should be placed close to pin 8 of Hall current sensor N2 during wiring. Capacitor C4 filters interference from the original power input, capacitor C8 filters interference between the original power input and the load power input, and capacitor C10 filters to make the input of the output amplifier of Hall current sensor N2 cleaner, thereby allowing adjustment of the output amplifier bandwidth; it is typically 1nF. The output linear region of Hall current sensor N2 is 0.5V to 4.5V, corresponding to a current of -10A to 10A, with an average of 2mV / 10mA.

[0057] In one embodiment of this application, the adaptive current detection circuit and the first-stage voltage conditioning circuit 20 include: a first rail-to-rail operational amplifier, a second rail-to-rail operational amplifier, resistors R1 to R7, capacitors C1, C2, C5, C6, C7, and a Zener diode V1. The first terminal of resistor R1 is connected to a reference voltage Vref, and the second terminal is connected to the first terminal of resistor R2 and the inverting input terminal of the first rail-to-rail operational amplifier. The second terminal of resistor R2 is connected to the first terminal of resistor R3, and the second terminal of resistor R3 is connected to the output terminal of the first rail-to-rail operational amplifier. The first terminal of capacitor C2 is connected to the reference voltage Vref, and the second terminal is grounded (GND). The first terminal of capacitor C1 is connected to the non-inverting supply voltage V5 of the first rail-to-rail operational amplifier, and the second terminal is grounded (GND). ND; The non-inverting input of the first rail-to-rail operational amplifier is connected to the VCC pin of the Hall current sensor through resistor R7; the non-inverting input of the second rail-to-rail operational amplifier is connected to the first terminal of resistor R6, and the second terminal of resistor R6 is grounded to GND; the first terminal of resistor R4 is connected to the output terminal of the second rail-to-rail operational amplifier, and the second terminal is connected to the first input terminal of the AD conversion circuit 40; the first terminal of capacitor C7 is connected to the non-inverting input terminal of the second rail-to-rail operational amplifier, and the second terminal is grounded to GND; the cathode of Zener diode V1 is connected to the non-inverting input terminal of the second rail-to-rail operational amplifier, and the second terminal is grounded to GND; the first terminal of capacitor C5 is connected to the second terminal of the fourth resistor R4, and both the second terminals are grounded to GND; the first terminal of capacitor C6 is connected to the second terminal of the fourth resistor R4, and both the second terminals are grounded to GND.

[0058] In one embodiment of this application, the adaptive current detection circuit and the secondary voltage conditioning circuit 30 include: a third rail-to-rail operational amplifier, a fourth rail-to-rail operational amplifier, resistors R8 to R14, capacitors C11 to C16, and a Zener diode V2; resistor R8 has its first end connected to the reference voltage Vref, and its second end connected to the first end of resistor R9 and the inverting input terminal of the third rail-to-rail operational amplifier; the second end of resistor R9 is connected to the first end of resistor R10, and the second end of resistor R10 is connected to the output terminal of the third rail-to-rail operational amplifier; the first end of capacitor C12 is connected to the reference voltage Vref, and its second end is grounded (GND); the first end of capacitor C11 is connected to the non-inverting supply voltage V5 of the third rail-to-rail operational amplifier, and its second end is grounded (GND); the non-inverting input terminal of the third rail-to-rail operational amplifier is connected to the VCC pin of the Hall current sensor through resistor R13; the first end of resistor R11 is connected to the fourth rail-to-rail operational amplifier... The output terminal of the operational amplifier is connected to the second input terminal of the AD conversion circuit 40; the first terminal of resistor R14 is connected to the second terminal of resistor R13, and the second terminal is grounded to GND; the first terminal of resistor R12 is connected to the output terminal of the third rail-to-rail operational amplifier, and the second terminal is connected to the non-inverting input terminal of the fourth rail-to-rail operational amplifier; the first terminal of capacitor C15 is connected to the non-inverting input terminal of the fourth rail-to-rail operational amplifier, and the second terminal is grounded to GND; the cathode of Zener diode V2 is connected to the non-inverting input terminal of the fourth rail-to-rail operational amplifier, and the second terminal is grounded to GND; the first terminal of capacitor C13 is connected to the second terminal of the fourth resistor R11, and the second terminals are all grounded to GND; the first terminal of capacitor C14 is connected to the second terminal of the fourth resistor R11, and the second terminals are all grounded to GND; the first terminal of capacitor C16 is connected to resistor R13, the V1OUT terminal of the Hall current sensor, and resistor R13, and the second terminal is connected to the second terminal of resistor R14 and grounded to GND.

[0059] The voltage conditioning circuit consists of precision rail-to-rail operational amplifiers N1 and N3, resistors R1-R14, capacitors C1-C2, C5-C7, C9, C11-C16, and Zener diodes V1-V2. The voltage conditioning circuit is divided into two stages. The first-stage voltage conditioning circuit 20 consists of N1A-N1B, resistors R1-R7, capacitors C1-C2, C5-C7, C9, and V1. The second-stage voltage conditioning circuit 30 consists of N3A-N3B, resistors R8-R14, capacitors C11-C16, and Zener diode V2. The first-stage voltage conditioning circuit 20 has a higher amplification factor than the second-stage voltage conditioning circuit 30, thus enabling it to achieve higher current detection accuracy and making it suitable for small current detection. The second-stage voltage conditioning circuit 30 has lower current detection accuracy but can detect a wider range of currents. Capacitor C1 provides power decoupling for N1 and is routed close to pin 8 of N1. Capacitor C2 filters interference on the reference voltage Vref line. Capacitors C5 and C6 filter input interference for AD1 and are routed close to the AD1 pin of the microprocessor. Capacitor C7 filters the influence of the input terminal of op-amp N1A and is routed close to pin 3 of N1. Capacitor C9 filters interference on the output line of the current-to-voltage conversion circuit 10. Resistors R2 and R3 are precision adjustment resistors, working together with resistor R1 to adjust the output amplification factor of op-amp N1B. Resistors R5 and R6 form a resistor divider circuit to adjust the input voltage of op-amp N1A. Together with Zener diode V1, they ensure that the input voltage of the microprocessor's AD1 does not exceed the pin's withstand voltage. Capacitor C11 provides power decoupling for N3 and is routed close to pin 8 of N3. Capacitor C12 filters interference on the reference voltage Vref line. Capacitors C13 and C14 filter input interference from AD2 and are routed close to the AD2 pin of the microprocessor. Capacitor C15 filters the influence of the input terminal of op-amp N3A and is routed close to pin 3 of N3. Capacitor C16 filters interference on the output line of the current-to-voltage conversion circuit 10. Resistors R9 and R10 are precision adjustment resistors, working together with resistor R8 to adjust the output amplification factor of op-amp N3B. Resistors R13 and R14 form a resistor divider circuit to adjust the input voltage of op-amp N3B. Zener diode V2 ensures that the input voltage of the microprocessor's AD2 does not exceed the pin's withstand voltage.

[0060] In one embodiment of this application, the adaptive current detection circuit and the AD conversion circuit 40 include:

[0061] The MCU has a 12-bit AD converter, and the AD converter performs data transfer and storage via DMA.

[0062] Specifically, the AD conversion circuit 40 is a 12-bit AD converter integrated into the microprocessor MCU. During software design, the AD converter is initialized to continuous scan mode. The AD converter performs data transfer and storage via DMA, and a timer update interrupt is enabled with an update period of T1. In the timer interrupt service routine, the sampled values ​​of AD1 and AD2 are filtered using the trimmean function to obtain sampled values ​​S1 and S2. Then, two current values ​​are calculated: I1 = 4 / 4096 * S1, I2 = 6 / 4096 * S2 + 4. When I1 < 4, I1 is valid; when I1 ≥ 4, I2 is valid.

[0063] Based on the above embodiments, this application also provides a detection device having the adaptive current detection circuit provided in any of the preceding embodiments.

[0064] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. An adaptive current detection circuit, characterized in that, include: Current-to-voltage conversion circuit, first-stage voltage conditioning circuit, second-stage voltage conditioning circuit, and AD conversion circuit; The output of the current-to-voltage conversion circuit is connected to the input of the first-stage voltage conditioning circuit and the input of the second-stage voltage conditioning circuit, respectively. The output of the first-stage voltage conditioning circuit and the output of the second-stage voltage conditioning circuit are connected to the two inputs of the AD conversion circuit, respectively. The current-to-voltage conversion circuit is used to acquire voltage signals based on a Hall current sensor. The first-level voltage conditioning circuit is used to condition the voltage signal based on the first set of rail-to-rail operational amplifiers to obtain the first voltage signal; The secondary voltage conditioning circuit is used to condition the voltage signal based on the second set of rail-to-rail operational amplifiers to obtain a second voltage signal, wherein the amplification factor of the primary voltage conditioning circuit is greater than that of the secondary voltage conditioning circuit. The AD conversion circuit is used to sample the first voltage signal to obtain a first sampling signal, and to sample the second voltage signal to obtain a second sampling signal. The converted first sampling signal and the converted second sampling signal are compared with a preset current threshold to obtain the detection current value.

2. The adaptive current detection circuit as described in claim 1, characterized in that, The adaptive current detection circuit includes: Hall effect current sensor, capacitors C4, C8, C3, C9 and C10; Among them, the first end of capacitor C4 is connected to the input original power supply ground terminal G, and the second end is connected to the IP+ pin of the Hall current sensor and the original power supply input terminal V28. The first end of capacitor C8 is connected to the IP+ pin of the Hall current sensor and the original power input terminal V28, and the second end is connected to the IP- pin of the Hall current sensor. The first end of capacitor C3 is connected to the VCC pin of the Hall current sensor and the power supply V5, and the second end is connected to digital ground GND. The first end of capacitor C10 is connected to the NC pin of the Hall current sensor, and the second end is connected to digital ground GND; The first end of capacitor C9 is connected to the V1OUT pin of the Hall current sensor, and the second end is connected to the digital ground GND and the GND pin of the Hall current sensor.

3. The adaptive current detection circuit as described in claim 1, characterized in that, The adaptive current detection circuit, the first-stage voltage conditioning circuit includes: The first rail-to-rail operational amplifier, the second rail-to-rail operational amplifier, resistors R1 to R7, capacitors C1, C2, C5, C6, C7, and Zener diode V1; Among them, the first end of resistor R1 is connected to the reference voltage Vref, and the second end is connected to the first end of resistor R2 and the inverting input of the first rail-to-rail operational amplifier. The second end of resistor R2 is connected to the first end of resistor R3, and the second end of resistor R3 is connected to the output terminal of the first rail-to-rail operational amplifier. The first terminal of capacitor C2 is connected to the reference voltage Vref, and the second terminal is grounded (GND). The first terminal of capacitor C1 is connected to the in-phase supply voltage V5 of the first rail-to-rail operational amplifier, and the second terminal is grounded to GND. The non-inverting input of the first rail-to-rail operational amplifier is connected to the VCC pin of the Hall current sensor through resistor R7. The non-inverting input terminal of the second rail-to-rail operational amplifier is connected to the first terminal of resistor R6, and the second terminal of resistor R6 is grounded to GND. The first end of resistor R4 is connected to the output of the second rail-to-rail operational amplifier, and the second end is connected to the first input of the AD conversion circuit. The first terminal of capacitor C7 is connected to the non-inverting input terminal of the second rail-to-rail operational amplifier, and the second terminal is grounded to GND. The cathode of Zener diode V1 is connected to the non-inverting input terminal of the second rail-to-rail operational amplifier, and the second terminal is grounded to GND. The first terminal of capacitor C5 is connected to the second terminal of the fourth resistor R4, and the second terminal is grounded to GND. The first terminal of capacitor C6 is connected to the second terminal of the fourth resistor R4, and the second terminal is grounded to GND.

4. The adaptive current detection circuit as described in claim 1, characterized in that, The adaptive current detection circuit and the secondary voltage conditioning circuit include: Third rail-to-rail operational amplifier, fourth rail-to-rail operational amplifier, resistors R8 to R14, capacitors C11 to C16, and Zener diode V2. Resistor R8 has its first terminal connected to the reference voltage Vref, its second terminal connected to the first terminal of resistor R9, and its third terminal connected to the inverting input of the rail-to-rail op-amp. Resistor R9, the second end of which is connected to the first end of resistor R10, and the second end of resistor R10 is connected to the output terminal of the third rail-to-rail operational amplifier; Capacitor C12 has its first terminal connected to the reference voltage Vref, and its second terminal grounded to GND. Capacitor C11, the first terminal is connected to the in-phase supply voltage V5 of the third rail-to-rail operational amplifier, and the second terminal is grounded GND; The third rail-to-rail operational amplifier has its non-inverting input connected to the VCC pin of the Hall current sensor via resistor R13. Resistor R11 has its first end connected to the output of the fourth rail-to-rail operational amplifier and its second end connected to the second input of the AD conversion circuit. Resistor R14, the first end is connected to the second end of resistor R13, and the second end is grounded (GND); Resistor R12, the first end is connected to the output of the third rail-to-rail operational amplifier, and the second end is connected to the non-inverting input of the fourth rail-to-rail operational amplifier; Capacitor C15, the first end is connected to the non-inverting input of the fourth rail-to-rail op-amp, and the second end is grounded to GND; Zener diode V2, cathode connected to the non-inverting input terminal of the fourth rail-to-rail operational amplifier, second terminal grounded to GND; Capacitor C13 has its first end connected to the second end of the fourth resistor R11, and both ends of the second end are grounded (GND). The first end of capacitor C14 is connected to the second end of the fourth resistor R11, and the second end of each capacitor is grounded (GND). Capacitor C16 has its first end connected to resistor R13 and the V1OUT terminal of the Hall current sensor and resistor R13, and its second end connected to the second end of resistor R14 and ground GND.

5. The adaptive current detection circuit as described in claim 1, characterized in that, The adaptive current detection circuit and the AD conversion circuit include: The MCU has a 12-bit AD converter, and the AD converter performs data transmission and storage via DMA.

6. A testing device, characterized in that, It has an adaptive current detection circuit as described in any one of claims 1-5.

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