Temperature compensation circuit and temperature compensation system for Hall sensor

Abstract

The utility model discloses a temperature compensation circuit and a temperature compensation system used for a Hall sensor, the circuit comprises a constant current module, a reverse amplification module, a voltage sampling module, a resistance value presetting module, a power supply positive electrode end I P1 and a circuit negative electrode end I P2, the power supply positive electrode end I P1 is connected with a Hall positive electrode end, and the circuit negative electrode end I P2 is connected with a Hall negative electrode end; the constant current module is connected with the reverse amplification module, the reverse amplification module is connected with the voltage sampling module, the voltage sampling module is connected with the constant current module, the resistance value presetting module is connected with the constant current module and the voltage sampling module, and the power supply positive electrode end I P1 is connected with the constant current module and the voltage sampling module. And the circuit negative electrode end I P2 is connected with the resistance value presetting module, the constant current module and the voltage sampling module. According to the scheme, negative benefits caused by temperature excursion of the Hall sensor can be reduced, and the requirement for high-precision magnetic field measurement is met.

Description

Technical Field

[0001] The utility model relates to the field of magnetic field measurement, in particular to a temperature compensation circuit and a temperature compensation system for a Hall sensor. Background Art

[0002] In the field of magnetic field measurement, measurement technology is mainly used to evaluate and analyze the intensity, direction and distribution characteristics of static or dynamic magnetic fields. In actual measurements, Hall sensors made of gallium arsenide are used in the range of 0T to 3T. This Hall sensor is used as a measuring probe in combination with a matching Gaussmeter, also known as a Teslameter, and is applied to magnetic field measurements in actual scenarios such as permanent magnet motors, magnets, and electromagnets.

[0003] Hall effect sensors made of gallium arsenide (GaAs) generally use constant current excitation, measuring the magnitude of the magnetic field and feeding it back proportionally to the output voltage. However, these sensors are subject to a certain degree of temperature drift, and precision measurement requires a constant temperature environment to avoid temperature drift. Existing technologies compensate for this temperature drift by measuring the temperature around the Hall effect sensor and then implementing an algorithm to compensate. However, in most cases, the temperature of the chip inside the Hall effect sensor is inconsistent with the temperature of the detection point, resulting in unsatisfactory compensation. Therefore, the industry needs to design a temperature compensation solution for Hall effect sensors to achieve a more ideal temperature compensation method. Utility Model Content

[0004] The technical problem to be solved by the present invention is: how to design a temperature compensation scheme for the Hall sensor to achieve a more ideal temperature compensation method, thereby reducing the negative effects caused by temperature drift of the Hall sensor and meeting the requirements of high-precision magnetic field measurement.

[0005] To solve the above problems, an embodiment of the present invention proposes a temperature compensation circuit for a Hall sensor, wherein the temperature compensation circuit is connected to the Hall sensor, and the Hall sensor includes a Hall positive terminal and a Hall negative terminal. The temperature compensation circuit includes: a constant current module, a reverse amplification module, a voltage sampling module, a resistance value preset module, a power supply positive terminal IP1, and a circuit negative terminal IP2. The power supply positive terminal IP1 is connected to the Hall positive terminal of the Hall sensor, and the circuit negative terminal IP2 is connected to the Hall negative terminal of the Hall sensor; the constant current module is connected to the reverse amplification module, the reverse amplification module is connected to the voltage sampling module, the voltage sampling module is connected to the constant current module, the resistance value preset module is connected to both the constant current module and the voltage sampling module, the power supply positive terminal IP1 is connected to both the constant current module and the voltage sampling module, and the circuit negative terminal IP2 is connected to the resistance value preset module, the constant current module, and the voltage sampling module.

[0006] Its further technical solution is that the voltage sampling module includes an instrument amplifier AU2C, a resistor R1, a capacitor C1, a capacitor C19, a capacitor C18, and a capacitor C23; the resistance value preset module is connected to the positive input terminal of the instrument amplifier AU2C, the positive input terminal of the instrument amplifier AU2C is also connected to the negative terminal IP2 of the circuit, the negative input terminal of the instrument amplifier AU2C is connected to the constant current module, the negative input terminal of the instrument amplifier AU2C is also connected to the positive power supply terminal IP1, the output terminal of the instrument amplifier AU2C is connected to the resistor R1, and the resistor R1 is connected to the reverse amplification module; the positive power supply terminal of the instrument amplifier AU2C is connected to the capacitor C1 and the capacitor C19 connected in parallel, and the capacitor C1 and the capacitor C19 are both grounded, and the negative power supply terminal of the instrument amplifier AU2C is connected to the capacitor C18 and the capacitor C23 connected in parallel, and the capacitor C18 and the capacitor C23 are both grounded. In one embodiment, the REF terminal of the instrumentation amplifier AU2C is connected to the capacitor C18 and also to the capacitor C23.

[0007] Its further technical solution is that the reverse amplification module includes a first amplifier AU1 B, the output end of the instrument amplifier AU2C is connected to the negative input end of the first amplifier AU1 B through the resistor R1, the positive input end of the first amplifier AU1 B is grounded, and the output end of the first amplifier AU1 B is connected to the constant current module.

[0008] A further technical solution is that the reverse amplification module also includes a resistor R2, a resistor R3, and a capacitor C25; the output end of the first amplifier AU1 B is connected to the resistor R2, the resistor R2 is connected to the resistor R3, and the resistor R3 is connected to the negative input end of the first amplifier AU1 B; the output end of the first amplifier AU1 B is connected to the capacitor C25, and the capacitor C25 is connected to the negative input end of the first amplifier AU1 B.

[0009] Its further technical solution is that the constant current module includes a second amplifier AU1A, a resistor R4, a resistor R8, and a capacitor C21; the positive input end of the second amplifier AU1A is connected to the output end of the first amplifier AU1 B of the reverse amplification module, the negative input end of the second amplifier AU1A is connected to the resistance value preset module, the output end of the second amplifier AU1A is connected to the resistor R8, the resistor R8 is connected to the positive power supply terminal IP1, the positive power supply terminal IP1 is connected to the resistor R4, the resistor R4 is connected to the capacitor C21, and the capacitor C21 is connected to the resistance value preset module.

[0010] Its further technical solution is that the constant current module also includes capacitor C22, capacitor C27, capacitor C20, and capacitor C26; the positive power supply terminal of the second amplifier AU1A is connected to the capacitor C22 and capacitor C27 connected in parallel, and the capacitor C22 and the capacitor C27 are both grounded, and the negative power supply terminal of the second amplifier AU1A is connected to the capacitor C20 and capacitor C26 connected in parallel, and the capacitor C20 and the capacitor C26 are both grounded.

[0011] A further technical solution is that the temperature compensation circuit further includes a resistor R5, one end of the resistor R5 is connected to the positive input terminal of the instrument amplifier AU2C, and the other end of the resistor R5 is grounded.

[0012] A further technical solution is that the resistance value preset module further includes a resistor R6 and a resistor R7 connected in parallel, the resistor R6 and the resistor R7 are connected to the reference voltage terminal VREF, and the resistor R6 and the resistor R7 are also connected to the circuit negative terminal IP2.

[0013] In a second aspect, an embodiment of the present invention further proposes a temperature compensation system, which includes a Hall sensor and a temperature compensation circuit as described in the first aspect, wherein the temperature compensation circuit is interconnected with the Hall sensor.

[0014] Based on the existing circuit, the present application analyzes that the sensor input resistance is also affected by temperature, and the temperature coefficient is 0.3% / °C. Together with the temperature drift coefficient of the output voltage of -0.06% / °C, as the temperature rises, the output voltage decreases, while the input resistance increases. As long as the change in input resistance is sampled, the temperature change can also be measured; and this is the temperature inside the sensor, that is, the Hall sensor, which truly reflects the temperature drift of the output voltage and the temperature drift of the input resistance. As long as the constant current value is adjusted to compensate according to this change, the same voltage can be output for the same magnetic field at different temperatures.

[0015] To this end, on the basis of the existing circuit, the AU1A operational amplifier, the resistor R6, the resistor R7 and the reference voltage terminal VREF form a constant current at the connection between IP1+ and IP2-. The IP1+ is the negative power supply terminal IP1, and the IP2- is the negative circuit terminal IP2. The reference voltage terminal VREF shown in the figure can be 2.5V, and the resistor R6 and the resistor R7 are connected in parallel to form 500 ohms. After calculation, it can be concluded that the basic constant current setting value is 5mA, which corresponds to (VREF-VAU1A non-inverting terminal) / 500 ohms, and a result of 5mA is obtained.

[0016] Furthermore, the solution described in this application adds an AU2C instrument amplifier to sample the voltage of the constant current input to the two ports IP1+ and IP2- of the sensor, and then reversely amplifies it through the AU1 B operational amplifier and inputs it to the AU1A non-inverting terminal to adjust the constant current value, thereby realizing the temperature compensation function of the sensor itself.

[0017] In one embodiment, the original constant current value remains unchanged, the temperature rises, and the voltage of the magnetic field feedback is originally to decrease. However, by sampling the voltage of the input terminals IP1+ and IP2- (that is, sampling the input resistance), this voltage increases due to the temperature rise, and is given to the non-inverting terminal of AU1A of the constant current control through reverse amplification, and the reference voltage is too high, thereby increasing the constant current setting value. Since the constant current value is directly proportional to the magnetic field feedback voltage, the increase in the constant current value compensates for the decrease in the magnetic field feedback voltage caused by the temperature rise. The amplification factor is 0.12684 times through fitting calculation of various parameters of the Hall sensor. Currently, the resistor R2 is 22 kilo-ohms, the resistor R3 is 3.3 kilo-ohms, and the resistor R1 is 200 kilo-ohms, thereby forming an amplification factor of 0.128 times.

[0018] The solution described in this application can meet the temperature compensation function and can adapt to different probes without increasing the difficulty of use. According to the actual comparison results, the temperature drift of the compensation circuit can be reduced from the original -0.06% / ℃ to within -0.006% / ℃, which reduces the technical parameter index of the temperature drift by an order of magnitude. The normal temperature change range does not affect the fluctuation of the measurement results, meeting the demand for high-precision measurement. In addition, in order to stabilize the probe temperature, the previous Gaussmeter generally needs to be turned on for half an hour before it is recommended to measure. After sampling this compensation circuit, the measurement can be carried out as soon as the power is turned on, and there will be no obvious measurement differences.

[0019] In summary, Hall effect sensors made of gallium arsenide generally use constant current excitation, where the magnitude of the measured magnetic field is directly proportional to the magnitude of the output voltage. However, these sensors are subject to a certain degree of temperature drift, and precision measurement requires a constant temperature environment, meaning that temperature drift must be avoided. In the prior art, to compensate for temperature drift, it is necessary to detect the temperature surrounding the Hall effect sensor and then implement compensation using an algorithm. However, in most cases, the temperature of the chip inside the Hall effect sensor is inconsistent with the temperature of the detection point, resulting in unsatisfactory compensation. The present application addresses this issue, and the solution described can reduce the negative effects of temperature drift in the Hall effect sensor, meeting the requirements for high-precision magnetic field measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is an overall circuit diagram of the temperature compensation circuit proposed in an embodiment of the present utility model.

[0022] Figure 2 This is an overall circuit block diagram of the temperature compensation circuit proposed in an embodiment of the present utility model.

[0023] Figure 3 This is a circuit diagram of a voltage sampling module of a temperature compensation circuit proposed in an embodiment of the present utility model.

[0024] Figure 4 This is a circuit diagram of the reverse amplification module of the temperature compensation circuit proposed in an embodiment of the present utility model.

[0025] Figure 5 This is a circuit diagram of a constant current module of a temperature compensation circuit proposed in an embodiment of the present utility model. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings of the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments. Similar component numbers in the drawings represent similar components. Obviously, the embodiments described below are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0027] It should be understood that the terms used in this specification of the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the embodiments of the present invention. As used in the specification of the embodiments of the present invention and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0028] Example

[0029] See also Figures 1 to 5This embodiment of the present invention provides a temperature compensation circuit for a Hall effect sensor. The temperature compensation circuit is connected to the Hall effect sensor, which includes a positive Hall effect terminal and a negative Hall effect terminal. The temperature compensation circuit includes: a constant current module, a reverse amplification module, a voltage sampling module, a resistance value preset module, a power supply positive terminal IP1, and a circuit negative terminal IP2. The power supply positive terminal IP1 is connected to the positive Hall effect terminal of the Hall effect sensor, and the circuit negative terminal IP2 is connected to the negative Hall effect terminal of the Hall effect sensor. The constant current module is connected to the reverse amplification module, the reverse amplification module is connected to the voltage sampling module, the voltage sampling module is connected to the constant current module, the resistance value preset module is connected to both the constant current module and the voltage sampling module, the power supply positive terminal IP1 is connected to both the constant current module and the voltage sampling module, and the circuit negative terminal IP2 is connected to both the resistance value preset module, the constant current module, and the voltage sampling module. In one embodiment, the Hall effect sensor is made of gallium arsenide.

[0030] In the above scheme, see Figure 1 as well as Figure 2 Under the influence of temperature on the Hall effect sensor, the current obtained by the voltage sampling module after sampling the positive power supply terminal IP1 and the negative circuit terminal IP2 also experiences temperature offset. The current change is reversely amplified by the operational amplifier of the reverse amplification module and input into the constant current module, which finally adjusts the current to alleviate the current offset. Furthermore, the resistance value preset module, namely the constant current value preset resistance module, is used to implement the constant current value preset resistance.

[0031] Its further technical solution is, see Figure 3 The voltage sampling module includes an instrument amplifier AU2C, a resistor R1, a capacitor C1, a capacitor C19, a capacitor C18, and a capacitor C23; the resistance value preset module is connected to the positive input terminal of the instrument amplifier AU2C, the positive input terminal of the instrument amplifier AU2C is also connected to the negative terminal IP2 of the circuit, the negative input terminal of the instrument amplifier AU2C is connected to the constant current module, the negative input terminal of the instrument amplifier AU2C is also connected to the positive power supply terminal IP1, the output terminal of the instrument amplifier AU2C is connected to the resistor R1, and the resistor R1 is connected to the reverse amplification module; the positive power supply terminal of the instrument amplifier AU2C is connected to the capacitor C1 and the capacitor C19 connected in parallel, and the capacitor C1 and the capacitor C19 are both grounded, and the negative power supply terminal of the instrument amplifier AU2C is connected to the capacitor C18 and the capacitor C23 connected in parallel, and the capacitor C18 and the capacitor C23 are both grounded.

[0032] In the above scheme, the instrument amplifier, referred to as INA, is an electronic amplifier specially designed for measuring and amplifying small signals. It is an improved version of the differential amplifier, has high precision and stability, and is widely used in scientific experiments, engineering testing, medical diagnosis and other fields.

[0033] Its further technical solution is, see Figure 4 The reverse amplification module includes a first amplifier AU1B, the output end of the instrument amplifier AU2C is connected to the negative input end of the first amplifier AU1B through the resistor R1, the positive input end of the first amplifier AU1B is grounded, and the output end of the first amplifier AU1B is connected to the constant current module.

[0034] Its further technical solution is to continue to refer to Figure 4 The reverse amplification module further includes a resistor R2, a resistor R3, and a capacitor C25; the output end of the first amplifier AU1B is connected to the resistor R2, the resistor R2 is connected to the resistor R3, and the resistor R3 is connected to the negative input end of the first amplifier AU1B; the output end of the first amplifier AU1B is connected to the capacitor C25, and the capacitor C25 is connected to the negative input end of the first amplifier AU1B.

[0035] Its further technical solution is, see Figure 5 The constant current module includes a second amplifier AU1A, a resistor R4, a resistor R8, and a capacitor C21; the positive input end of the second amplifier AU1A is connected to the output end of the first amplifier AU1B of the reverse amplification module, the negative input end of the second amplifier AU1A is connected to the resistance value preset module, the output end of the second amplifier AU1A is connected to the resistor R8, the resistor R8 is connected to the positive power supply terminal IP1, the positive power supply terminal IP1 is connected to the resistor R4, the resistor R4 is connected to the capacitor C21, and the capacitor C21 is connected to the resistance value preset module.

[0036] Its further technical solution is to continue to refer to Figure 5 The constant current module further includes a capacitor C22, a capacitor C27, a capacitor C20, and a capacitor C26; the positive power supply terminal of the second amplifier AU1A is connected to the capacitor C22 and the capacitor C27 connected in parallel, and the capacitor C22 and the capacitor C27 are both grounded; the negative power supply terminal of the second amplifier AU1A is connected to the capacitor C20 and the capacitor C26 connected in parallel, and the capacitor C20 and the capacitor C26 are both grounded.

[0037] In the above scheme, under the influence of temperature on the Hall sensor, the current obtained by the instrument amplifier AU2C after sampling the positive terminal IP1 of the power supply and the negative terminal IP2 of the circuit also shifts; the change in current is reversely amplified by AU1B and input to AU1A, and finally AU1A adjusts the current to alleviate the previous current shift.

[0038] A further technical solution is that the temperature compensation circuit further includes a resistor R5, one end of the resistor R5 is connected to the positive input terminal of the instrument amplifier AU2C, and the other end of the resistor R5 is grounded.

[0039] A further technical solution is that the resistance value preset module further includes a resistor R6 and a resistor R7 connected in parallel, the resistor R6 and the resistor R7 are connected to the reference voltage terminal VREF, and the resistor R6 and the resistor R7 are also connected to the circuit negative terminal IP2.

[0040] A further technical solution is provided in an embodiment of the present invention, which includes a temperature compensation system comprising a Hall sensor and a temperature compensation circuit as described in the above embodiment, wherein the temperature compensation circuit is interconnected with the Hall sensor. The temperature compensation system can significantly reduce the temperature drift of the Hall sensor's magnetic field measurement results, thereby meeting the requirements for high-precision measurement.

[0041] In summary, Hall effect sensors made of gallium arsenide generally use constant current excitation, where the magnitude of the measured magnetic field is directly proportional to the magnitude of the output voltage. However, these sensors are subject to a certain degree of temperature drift, and precision measurement requires a constant temperature environment, meaning that temperature drift must be avoided. In the prior art, to compensate for temperature drift, it is necessary to detect the temperature surrounding the Hall effect sensor and then implement compensation using an algorithm. However, in most cases, the temperature of the chip inside the Hall effect sensor is inconsistent with the temperature of the detection point, resulting in unsatisfactory compensation. The present application addresses this issue, and the solution described can reduce the negative effects of temperature drift in the Hall effect sensor, meeting the requirements for high-precision magnetic field measurement.

[0042] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0044] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0045] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0046] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0047] Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, as long as these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations.

[0048] The above description is a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A temperature compensation circuit for a Hall sensor, characterized in that: The temperature compensation circuit is connected to a Hall sensor, the Hall sensor includes a Hall positive terminal and a Hall negative terminal, and the temperature compensation circuit includes: Constant current module, reverse amplification module, voltage sampling module, resistance value preset module, power supply positive terminal IP1, circuit negative terminal IP2, the power supply positive terminal IP1 is connected to the Hall positive terminal of the Hall sensor, and the circuit negative terminal IP2 is connected to the Hall negative terminal of the Hall sensor; The constant current module is connected to the reverse amplification module, the reverse amplification module is connected to the voltage sampling module, the voltage sampling module is connected to the constant current module, the resistance value preset module is connected to the constant current module and the voltage sampling module, the power supply positive terminal IP1 is connected to the constant current module and the voltage sampling module, and the circuit negative terminal IP2 is connected to the resistance value preset module, the constant current module and the voltage sampling module.

2. The temperature compensation circuit according to claim 1, wherein: The voltage sampling module includes an instrument amplifier AU2C, a resistor R1, a capacitor C1, a capacitor C19, a capacitor C18, and a capacitor C23; the resistance value preset module is connected to the positive input terminal of the instrument amplifier AU2C, the positive input terminal of the instrument amplifier AU2C is also connected to the negative terminal IP2 of the circuit, the negative input terminal of the instrument amplifier AU2C is connected to the constant current module, the negative input terminal of the instrument amplifier AU2C is also connected to the positive power supply terminal IP1, the output terminal of the instrument amplifier AU2C is connected to the resistor R1, and the resistor R1 is connected to the reverse amplification module; the positive power supply terminal of the instrument amplifier AU2C is connected to the capacitor C1 and the capacitor C19 connected in parallel, and the capacitor C1 and the capacitor C19 are both grounded, and the negative power supply terminal of the instrument amplifier AU2C is connected to the capacitor C18 and the capacitor C23 connected in parallel, and the capacitor C18 and the capacitor C23 are both grounded.

3. The temperature compensation circuit according to claim 2, wherein: The reverse amplification module includes a first amplifier AU1 B, the output end of the instrument amplifier AU2C is connected to the negative input end of the first amplifier AU1 B through the resistor R1, the positive input end of the first amplifier AU1 B is grounded, and the output end of the first amplifier AU1 B is connected to the constant current module.

4. The temperature compensation circuit according to claim 3, wherein: The reverse amplification module also includes a resistor R2, a resistor R3, and a capacitor C25; the output end of the first amplifier AU1 B is connected to the resistor R2, the resistor R2 is connected to the resistor R3, and the resistor R3 is connected to the negative input end of the first amplifier AU1 B; the output end of the first amplifier AU1 B is connected to the capacitor C25, and the capacitor C25 is connected to the negative input end of the first amplifier AU1 B.

5. The temperature compensation circuit according to claim 4, wherein: The constant current module includes a second amplifier AU1A, a resistor R4, a resistor R8, and a capacitor C21; the positive input end of the second amplifier AU1A is connected to the output end of the first amplifier AU1 B of the reverse amplification module, the negative input end of the second amplifier AU1A is connected to the resistance value preset module, the output end of the second amplifier AU1A is connected to the resistor R8, the resistor R8 is connected to the positive power supply terminal IP1, the positive power supply terminal IP1 is connected to the resistor R4, the resistor R4 is connected to the capacitor C21, and the capacitor C21 is connected to the resistance value preset module.

6. The temperature compensation circuit according to claim 5, wherein: The constant current module also includes capacitor C22, capacitor C27, capacitor C20, and capacitor C26; the positive power supply terminal of the second amplifier AU1A is connected to the capacitor C22 and capacitor C27 connected in parallel, and the capacitor C22 and the capacitor C27 are both grounded, and the negative power supply terminal of the second amplifier AU1A is connected to the capacitor C20 and capacitor C26 connected in parallel, and the capacitor C20 and the capacitor C26 are both grounded.

7. The temperature compensation circuit according to claim 2, wherein: The temperature compensation circuit further includes a resistor R5 , one end of the resistor R5 is connected to the positive input terminal of the instrument amplifier AU2C, and the other end of the resistor R5 is grounded.

8. The temperature compensation circuit according to claim 2, wherein: The resistance value preset module further includes a resistor R6 and a resistor R7 connected in parallel. The resistor R6 and the resistor R7 are connected to the reference voltage terminal VREF. The resistor R6 and the resistor R7 are also connected to the circuit negative terminal IP2.

9. A temperature compensation system, characterized in that: The temperature compensation system includes a Hall sensor and also includes a temperature compensation circuit according to any one of claims 1 to 8, wherein the temperature compensation circuit is interconnected with the Hall sensor.

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