Hall sensor temperature compensation circuit and method

Abstract

The application provides a Hall sensor temperature compensation circuit and method, which converts temperature into a voltage signal through a temperature-sensitive resistor of a sampling module to obtain a sampling voltage, a control module generates a first control signal and a second control signal according to the sampling voltage and a feedback voltage, a compensation module adjusts a driving voltage of the Hall sensor to a target driving voltage at a corresponding temperature according to the first control signal and the second control signal, samples the driving voltage to obtain the feedback voltage, a driving amplification module drives the Hall sensor through the target driving voltage at the corresponding temperature and amplifies an output voltage of the Hall sensor, so that a reference voltage at the corresponding temperature is stabilized as a target reference voltage. The application determines the target driving voltage at the corresponding temperature according to the sampling voltage, quickly adjusts the driving voltage of the Hall sensor, realizes temperature compensation, is suitable for a wide range, can be applied to a low-power portable sensor, and ensures high temperature compensation precision.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and in particular to a Hall sensor temperature compensation circuit and method. Background Technology

[0002] Hall effect sensors are sensors based on the Hall effect of semiconductor materials in response to magnetic fields. They achieve electro-magnetic-electrical conversion and are generally used to measure changes in magnetic fields or currents, commonly found in non-contact detection fields such as displacement and rotational speed. However, the performance of the semiconductor materials in Hall effect sensors is affected by temperature. The Hall coefficient and the equivalent input / output impedance of the device change with temperature, becoming major factors affecting the output accuracy of the Hall effect sensor. Currently, there are many methods for temperature compensation of Hall effect outputs, which can be divided into open-loop and closed-loop based on the signal loop, and analog and digital based on signal processing. In related technologies, traditional temperature compensation structures for Hall effect sensors are complex to design, and the adjustment steps are cumbersome in practical applications. In some low-power portable sensors, the accuracy of conventional temperature compensation circuits is poor, resulting in compensation deviations and high production costs.

[0003] Therefore, how to provide a high-precision temperature compensation circuit that can be applied to low-power Hall sensors is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the present invention provides a Hall sensor temperature compensation circuit and method to solve the above technical problems.

[0005] To achieve the above and other related objectives, the technical solution provided in this application is as follows.

[0006] This application provides a Hall sensor temperature compensation circuit, including:

[0007] The sampling module samples the temperature using a thermistor to obtain the sampling voltage;

[0008] The control module is connected to the sampling voltage and the feedback voltage, and generates a first control signal and a second control signal based on the sampling voltage and the feedback voltage.

[0009] The compensation module is connected to the first control signal and the second control signal. It compensates and adjusts the driving voltage of the Hall sensor according to the first control signal and the second control signal, and samples the driving voltage to obtain the feedback voltage.

[0010] The drive amplification module is connected to the drive voltage. It drives the Hall sensor through the drive voltage and amplifies the output voltage of the Hall sensor to obtain the reference voltage.

[0011] The compensation module adjusts the driving voltage to the target driving voltage at the corresponding temperature according to the first control signal and the second control signal, so that the reference voltage at the corresponding temperature is stabilized as the target reference voltage.

[0012] Optionally, the sampling module includes a thermistor, a first resistor, a first capacitor, and a second capacitor. One end of the first resistor is connected to a first power supply voltage, and the other end of the first resistor is grounded after passing through a series-connected thermistor. One end of the first capacitor is connected to the first power supply voltage, and the other end of the first capacitor is grounded. One end of the second capacitor is connected to the other end of the first resistor, and the other end of the second capacitor is grounded. The other end of the first resistor outputs the sampling voltage.

[0013] Optionally, the compensation module includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first diode, a second diode, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, and a first operational amplifier. The cathode of the first diode is connected to the inverting input terminal of the first operational amplifier via the second resistor in series. The cathode of the first diode is also connected to the anode of the second diode. The inverting input terminal of the first operational amplifier is grounded via the third capacitor in series. The inverting input terminal of the first operational amplifier is also connected to the output terminal of the first operational amplifier via the fifth capacitor in series. One end of the third resistor is connected to the second power supply voltage, and the other end of the third resistor is connected to the second power supply voltage via the second resistor in series. The fourth resistor is grounded, the other end of the third resistor is connected to the non-inverting input of the first operational amplifier, the other end of the third resistor is also grounded through the fourth capacitor connected in series, the ground terminal of the first operational amplifier is grounded, the power supply terminal of the first operational amplifier is connected to the second power supply voltage, the power supply terminal of the first operational amplifier is also grounded through the sixth capacitor connected in series, the output terminal of the first operational amplifier is also grounded through the fifth resistor and the seventh capacitor connected in series, wherein the anode of the first diode is connected to the first control signal, the cathode of the second diode is connected to the second control signal, the output terminal of the first operational amplifier outputs the driving voltage, and the common terminal of the fifth resistor and the seventh capacitor outputs the feedback voltage.

[0014] Optionally, the drive amplification module includes a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, and a second operational amplifier. One end of the sixth resistor is connected to the second power supply voltage, and the other end of the sixth resistor is connected to one end of the seventh resistor. The other end of the sixth resistor is also connected to the power supply terminal of the Hall sensor. The ground terminal of the Hall sensor is grounded through the eighth resistor connected in series. The first output terminal of the Hall sensor is grounded through the eighth capacitor connected in series. The first output terminal of the Hall sensor is also connected to the inverting input terminal of the second operational amplifier through the ninth resistor connected in series. The inverting input terminal of the second operational amplifier is also connected to the output terminal of the second operational amplifier through the thirteenth resistor connected in series. The tenth capacitor and the... Thirteen resistors are connected in parallel. The second output terminal of the Hall sensor is grounded after passing through the ninth capacitor in series. The second output terminal of the Hall sensor is also connected to the non-inverting input terminal of the second operational amplifier after passing through the tenth resistor in series. One end of the eleventh resistor is connected to the second power supply voltage, and the other end of the eleventh resistor is grounded after passing through the twelfth resistor in series. The other end of the eleventh resistor is also connected to the non-inverting input terminal of the second operational amplifier. The power supply terminal of the second operational amplifier is connected to the second power supply voltage. The power supply terminal of the second operational amplifier is also grounded after passing through the twelfth capacitor in series. One end of the eleventh capacitor is connected to the non-inverting input terminal of the second operational amplifier, and the other end of the eleventh capacitor is connected to the ground terminal of the second operational amplifier. The ground terminal of the second operational amplifier is grounded. The other end of the seventh resistor is connected to the driving voltage. The output terminal of the second operational amplifier outputs the reference voltage.

[0015] Optionally, the control module includes an analog-to-digital conversion unit, an arithmetic unit, and a storage unit. The analog-to-digital conversion unit performs analog-to-digital conversion on the sampled voltage to obtain the real-time temperature. The storage unit stores a temperature test calibration table, which consists of the mapping relationship between different temperatures and the target driving voltage at the corresponding temperature.

[0016] Optionally, the arithmetic unit acquires the real-time temperature and obtains the target driving voltage at the real-time temperature according to the temperature test calibration table, obtains the real-time voltage of the driving voltage based on the feedback voltage, and adjusts the real-time voltage of the driving voltage to the target driving voltage through the first control signal and the second control signal.

[0017] This application also provides a Hall sensor temperature compensation method, which is applied to the Hall sensor temperature compensation circuit as described above, including:

[0018] The temperature is sampled by the sampling module to obtain the sampling voltage;

[0019] The control module generates a first control signal and a second control signal based on the sampled voltage and the feedback voltage;

[0020] The compensation module adjusts the driving voltage according to the first control signal and the second control signal to adjust the driving voltage to the target driving voltage at the corresponding temperature, and samples the driving voltage to obtain the feedback voltage.

[0021] The drive amplification module drives the Hall sensor with the adjusted drive voltage and amplifies the output voltage of the Hall sensor to stabilize the reference voltage at the corresponding temperature as the target reference voltage.

[0022] Optionally, the Hall sensor temperature compensation method further includes: adjusting the temperature of the Hall sensor temperature compensation circuit to a reference temperature, and obtaining a reference voltage at the reference temperature as a target reference voltage; adjusting the temperature of the Hall sensor temperature compensation circuit according to a preset step within a preset temperature range, adjusting the driving voltage through a first control signal and a second control signal, adjusting the reference voltage at the corresponding temperature to the target reference voltage, and obtaining the driving voltage at the corresponding temperature as the target driving voltage for the corresponding temperature; establishing a temperature test calibration table based on the mapping relationship between different temperatures and the corresponding target driving voltages, and storing the temperature test calibration table in a storage unit.

[0023] Optionally, the real-time temperature of the Hall sensor temperature compensation circuit is obtained based on the sampling voltage, and the target driving voltage at the real-time temperature is obtained based on the temperature test calibration table; the real-time voltage of the driving voltage is obtained based on the feedback voltage, and the levels of the first control signal and the second control signal are controlled according to the real-time voltage of the driving voltage and the target driving voltage; the real-time voltage of the driving voltage is increased or decreased by the first control signal and the second control signal until the real-time voltage of the driving voltage is equal to the target driving voltage, so that the reference voltage at the real-time temperature is stabilized as the target reference voltage.

[0024] This application provides a Hall sensor temperature compensation circuit and method. The circuit includes a sampling module, a control module, a compensation module, and a drive amplification module. The sampling module converts temperature into a voltage signal through a thermistor to obtain a sampling voltage. The control module generates a first control signal and a second control signal based on the sampling voltage and the feedback voltage. The compensation module adjusts the drive voltage of the Hall sensor according to the first and second control signals to adjust the drive voltage to the target drive voltage at the corresponding temperature and samples the drive voltage to obtain a feedback voltage. The drive amplification module drives the Hall sensor with the target drive voltage at the corresponding temperature and amplifies the output voltage of the Hall sensor to stabilize the reference voltage at the corresponding temperature as the target reference voltage. This application converts temperature into a signal, obtains the target drive voltage at the corresponding temperature through sampling voltage, and adjusts the drive voltage of the Hall sensor to the target drive voltage at the corresponding temperature. This ensures that the reference voltage output by the Hall sensor is not affected by temperature. The circuit structure is simple, facilitates rapid adjustment of temperature compensation for the Hall sensor, has a wide range of applications, can be used in low-power portable sensors, ensures high-precision temperature compensation, and has high reliability. Attached Figure Description

[0025] Figure 1 This is a block diagram of a Hall sensor temperature compensation circuit proposed in an exemplary embodiment of this application;

[0026] Figure 2 This is a detailed structural diagram of the sampling module in an exemplary embodiment of this application;

[0027] Figure 3 This is a detailed structural diagram of the compensation module in an exemplary embodiment of this application;

[0028] Figure 4 This is a detailed structural diagram of the driving amplification module in an exemplary embodiment of this application;

[0029] Figure 5 This is a block diagram of the control module in an exemplary embodiment of this application;

[0030] Figure 6 This is a flowchart of a Hall sensor temperature compensation method in an exemplary embodiment of this application. Detailed Implementation

[0031] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0032] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0033] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0034] The inventors discovered that Hall sensors are sensors based on the Hall effect of certain semiconductor materials on magnetic fields, achieving electro-magnetic-electrical conversion. They are generally used to measure changes in magnetic fields or currents and are commonly used in non-contact detection fields such as displacement and rotational speed. However, the performance of the semiconductor materials in Hall sensors is affected by temperature; their Hall coefficient and the device's equivalent input and output impedance change with temperature, becoming the main factors affecting the output accuracy of Hall sensors. Currently, there are many methods for temperature compensation of Hall outputs, which can be divided into open-loop and closed-loop types based on the signal loop, and analog and digital types based on signal processing. In related technologies, traditional temperature compensation structures for Hall sensors are complex to design, and the adjustment steps are cumbersome in practical applications. In some low-power portable sensors, the accuracy of conventional temperature compensation circuits is poor, with compensation deviations, and production costs are high.

[0035] To solve the above problems, the sampling module converts the temperature into an electrical signal to obtain a sampling voltage; the control module generates a first control signal and a second control signal based on the sampling voltage and the feedback voltage; the compensation module adjusts the driving voltage of the Hall sensor based on the first control signal and the second control signal, and samples the driving voltage to obtain a feedback voltage; the drive amplification module drives the Hall sensor through the driving voltage and amplifies the output voltage of the Hall sensor to obtain a reference voltage.

[0036] Please see Figure 1 , Figure 1 This is a block diagram of a Hall sensor temperature compensation circuit according to an exemplary embodiment of this application. Figure 1 As shown, this application provides a Hall sensor temperature compensation circuit, including:

[0037] The sampling module samples the temperature using a thermistor to obtain the sampling voltage V0;

[0038] The control module is connected to the sampling voltage V0 and the feedback voltage V. F Based on the sampling voltage V0 and the feedback voltage V F Generate the first control signal Signal_1 and the second control signal Signal_2;

[0039] The compensation module is connected to the first control signal Signal_1 and the second control signal Signal_2, and adjusts the drive voltage V of the Hall sensor according to the first control signal Signal_1 and the second control signal Signal_2. D Compensation and adjustment are performed, and the driving voltage V is adjusted. D Sampling is performed to obtain the feedback voltage V F ;

[0040] Drive the amplifier module, connected to the drive voltage V D By driving voltage V D The Hall sensor is driven, and its output voltage is amplified to obtain a reference voltage.

[0041] The compensation module adjusts the driving voltage V according to the first control signal Signal_1 and the second control signal Signal_2. D Adjust the driving voltage to the target voltage at the corresponding temperature so that the reference voltage at the corresponding temperature is stabilized as the target reference voltage.

[0042] Please see Figure 2 , Figure 2 This is a structural diagram of the sampling module in an exemplary embodiment of this application.

[0043] In detail, such as Figure 2 As shown, the sampling module includes a thermistor RT1, a first resistor R1, a first capacitor C1, and a second capacitor C2. One end of the first resistor R1 is connected to the first power supply voltage VCC, and the other end of the first resistor R1 is grounded after passing through the thermistor RT1 connected in series. One end of the first capacitor C1 is connected to the first power supply voltage VCC, and the other end of the first capacitor C1 is grounded. One end of the second capacitor C2 is connected to the other end of the first resistor R1, and the other end of the second capacitor C2 is grounded. The other end of the first resistor R1 outputs the sampling voltage V0.

[0044] Please see Figure 3 , Figure 3 This is a detailed structural diagram of the compensation module in an exemplary embodiment of this application.

[0045] In detail, such as Figure 3 As shown, the compensation module includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first diode D1, a second diode D2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, and a first operational amplifier U1. The cathode of the first diode D1 is connected to the inverting input terminal of the first operational amplifier U1 via the second resistor R2 in series. The cathode of the first diode D1 is also connected to the anode of the second diode D2. The inverting input terminal of the first operational amplifier U1 is also grounded via the third capacitor C3 in series. The inverting input terminal of the first operational amplifier U1 is also connected to the output terminal of the first operational amplifier U1 via the fifth capacitor C5 in series. One end of the third resistor R3 is connected to the second power supply voltage VDD. The other end of resistor R3 is grounded after passing through the fourth resistor R4 connected in series. The other end of the third resistor R3 is also connected to the non-inverting input of the first operational amplifier U1. The other end of the third resistor R3 is also grounded after passing through the fourth capacitor C4 connected in series. The ground terminal of the first operational amplifier U1 is grounded. The power supply terminal of the first operational amplifier U1 is connected to the second power supply voltage VDD. The power supply terminal of the first operational amplifier U1 is also grounded after passing through the sixth capacitor C6 connected in series. The output terminal of the first operational amplifier U1 is also grounded after passing through the fifth resistor R5 and the seventh capacitor C7 connected in series. The anode of the first diode D1 is connected to the first control signal Signal_1, the cathode of the second diode D2 is connected to the second control signal Signal_2, and the output terminal of the first operational amplifier U1 outputs a drive voltage V. D The common terminal of the fifth resistor R5 and the seventh capacitor C7 outputs a feedback voltage V. F .

[0046] Please see Figure 4 , Figure 4 This is a detailed structural diagram of the driving amplification module in an exemplary embodiment of this application.

[0047] In detail, such as Figure 4As shown, the drive amplifier module includes a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, an eighth capacitor C8, a ninth capacitor C9, a tenth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12, a second operational amplifier U2, and a Hall sensor T1. One end of the sixth resistor R6 is connected to the second power supply voltage VDD, and the other end of the sixth resistor R6 is connected to one end of the seventh resistor R7. The other end of the sixth resistor R6 is also connected to the power supply terminal of the Hall sensor T1. The ground terminal of the Hall sensor T1 is grounded through the eighth resistor R8 connected in series. The first output terminal of the Hall sensor T1 is grounded through the eighth capacitor C8 connected in series. The first output terminal of the Hall sensor T1 is also connected to the inverting input terminal of the second operational amplifier U2 through the ninth resistor R9 connected in series. The inverting input terminal of the second operational amplifier U2 is also connected to the second operational amplifier U2 through the thirteenth resistor R13 connected in series. The output of operational amplifier U2 is connected in parallel with the tenth capacitor C10 and the thirteenth resistor R13. The second output of Hall sensor T1 is grounded after passing through the ninth capacitor C9 connected in series. The second output of Hall sensor T1 is also connected to the non-inverting input of the second operational amplifier U2 after passing through the tenth resistor R10 connected in series. One end of the eleventh resistor R11 is connected to the second power supply voltage VDD. The other end of the eleventh resistor R11 is grounded after passing through the twelfth resistor R12 connected in series. The other end of the eleventh resistor R11 is also connected to the non-inverting input of the second operational amplifier U2. The power supply terminal of the second operational amplifier U2 is connected to the second power supply voltage VDD. The power supply terminal of the second operational amplifier U2 is also grounded after passing through the twelfth capacitor C12 connected in series. One end of the eleventh capacitor C11 is connected to the non-inverting input of the second operational amplifier U2. The other end of the eleventh capacitor C11 is connected to the ground terminal of the second operational amplifier U2. The ground terminal of the second operational amplifier U2 is grounded. The other end of the seventh resistor R7 is connected to the driving voltage V. D The second operational amplifier U2 outputs a reference voltage V. OUT .

[0048] Please see Figure 5 , Figure 5 This is a block diagram of the control module in an exemplary embodiment of this application.

[0049] In detail, such as Figure 5 As shown, the control module includes an analog-to-digital conversion unit, an arithmetic unit, and a storage unit. The analog-to-digital conversion unit performs analog-to-digital conversion on the sampled voltage to obtain the real-time temperature. The storage unit stores a temperature test calibration table, which consists of the mapping relationship between different temperatures and the target driving voltage at the corresponding temperature.

[0050] More specifically, the arithmetic unit acquires the real-time temperature and obtains the target driving voltage at the real-time temperature according to the temperature test calibration table, obtains the real-time voltage of the driving voltage based on the feedback voltage, and adjusts the real-time voltage of the driving voltage to the target driving voltage through the first control signal and the second control signal.

[0051] Please see Figures 1-5 The working principle of the Hall sensor temperature compensation circuit provided in this application is as follows:

[0052] The method for obtaining the temperature test calibration table is as follows: place the Hall sensor temperature compensation circuit in a temperature test chamber with a constant current or permanent magnet, select a certain temperature as the reference temperature, for example, the reference temperature is 25℃, and record the reference voltage output of the Hall sensor temperature compensation circuit at the reference temperature as the target reference voltage. The preset temperature range is [-45℃~125℃]. The step interval between two adjacent temperatures is set to 10℃. The Hall sensor temperature compensation circuit is placed in a temperature test chamber under the step temperature. The real-time temperature of the Hall sensor temperature compensation circuit is obtained by sampling the voltage. When the real-time temperature is higher than the reference temperature, the corresponding reference voltage output by the Hall sensor is lower than the target reference voltage. The driving voltage of the Hall sensor is charged to stabilize the reference voltage output by the Hall sensor at the real-time temperature to the target reference voltage. The target driving voltage at the real-time temperature is recorded. When the real-time temperature is lower than the reference temperature, the corresponding reference voltage output by the Hall sensor is higher than the target reference voltage. The driving voltage of the Hall sensor is discharged to stabilize the reference voltage output by the Hall sensor at the real-time temperature to the target reference voltage. The target driving voltage at the real-time temperature is recorded. The mapping relationship between different temperatures and the target driving voltage at the corresponding temperature is obtained, i.e., the temperature measurement calibration table.

[0053] The temperature measurement calibration table is shown in Table 1:

[0054] Table 1

[0055]

[0056]

[0057] If the real-time temperature is not in the temperature measurement calibration table, linear interpolation can be used to perform linear calculations on the two stable values ​​in the table to obtain the target driving voltage corresponding to the real-time temperature. For example, if the detected real-time temperature is T1 = 30℃, and there is no corresponding target driving voltage in the temperature measurement calibration table, the control module will perform linear calculations on the two adjacent temperatures. The two adjacent points (T2 = 25℃, V1_25) and (T3 = 35℃, V1_35) will be linearly calculated to obtain the target driving voltage V1_30 corresponding to the real-time temperature of 30℃.

[0058] The expression for determining the target driving voltage using linear interpolation is shown in expression (1):

[0059]

[0060] In expression (1), V1_T1 is the target driving voltage for the real-time temperature, V1_T3 is the target driving voltage for the first adjacent temperature, V1_T2 is the target driving voltage for the second adjacent temperature, T1 is the real-time temperature, T2 is the second adjacent temperature, and T3 is the first adjacent temperature. The first adjacent temperature T3 is greater than the real-time temperature T1, and the real-time temperature T1 is greater than the second adjacent temperature T2.

[0061] The temperature is detected in real time by the thermistor RT1 in the sampling module, and the sampling voltage V0 is obtained. The sampling voltage V0 is input to the control module, and the analog-to-digital converter performs analog-to-digital conversion on the sampling voltage to obtain the real-time temperature. When the detected real-time temperature is higher than the reference temperature, the target driving voltage at the real-time temperature is obtained through the temperature test calibration table. The real-time driving voltage is determined based on the feedback voltage. If the real-time driving voltage is lower than the target driving voltage, the control module generates a high-level first control signal and a high-level second control signal. The compensation module charges the real-time driving voltage of the Hall sensor. The current increases the voltage at the inverting input of the first operational amplifier through the first diode D1, thereby increasing the real-time driving voltage V. D The charging process continues until the real-time driving voltage equals the target driving voltage at the real-time temperature. At this point, the control module switches the first control signal to a low level while keeping the second control signal high, stopping the charging of the Hall sensor's driving voltage. Almost no current flows through the second resistor R2. When the detected real-time temperature is lower than the reference temperature, the target driving voltage at the real-time temperature is obtained using a temperature calibration table. The real-time driving voltage is determined based on the feedback voltage. If the real-time driving voltage is greater than the target driving voltage, the control module generates a low-level first control signal and a low-level second control signal. The inverting input of the first operational amplifier U1 discharges through the second diode D2 in the compensation module to reduce the real-time driving voltage V. DThe discharge of the Hall sensor's driving voltage is stopped when the real-time driving voltage equals the target driving voltage at the real-time temperature. The control module maintains the first control signal at a low level and the second control signal transitions from low to high. When the real-time temperature equals the reference temperature, the target driving voltage at the real-time temperature is obtained through a temperature calibration table. The real-time driving voltage is determined based on the feedback voltage. If the real-time driving voltage equals the target driving voltage, the control module generates a low-level first control signal and a high-level second control signal to ensure no current flows through the second resistor R2. This allows the driving voltage output by the compensation module to maintain a certain voltage value for a longer period, blocking most of the current energy consumption. In these three cases, compensation for the Hall sensor at different temperatures is achieved, ensuring that the reference voltage output by the Hall sensor remains stable at the target reference voltage at different temperatures.

[0062] Please see Figure 6 , Figure 6 This is a flowchart of a Hall sensor temperature compensation method in an exemplary embodiment of this application.

[0063] like Figure 6 This application also provides a Hall sensor temperature compensation method, which is applied to the Hall sensor temperature compensation circuit described above, and the method includes at least steps S610 to S640:

[0064] S610. The temperature is sampled through the sampling module to obtain the sampling voltage;

[0065] S620, the control module generates a first control signal and a second control signal based on the sampled voltage and the feedback voltage;

[0066] S630, the compensation module adjusts the driving voltage according to the first control signal and the second control signal, adjusts the driving voltage to the target driving voltage at the corresponding temperature, and samples the driving voltage to obtain the feedback voltage;

[0067] S640, the drive amplification module drives the Hall sensor through the adjusted drive voltage and amplifies the output voltage of the Hall sensor so that the reference voltage at the corresponding temperature is stabilized as the target reference voltage.

[0068] In detail, the Hall sensor temperature compensation method further includes: adjusting the temperature of the Hall sensor temperature compensation circuit to a reference temperature, and obtaining a reference voltage at the reference temperature as a target reference voltage; within a preset temperature range, adjusting the temperature of the Hall sensor temperature compensation circuit according to a preset step, adjusting the driving voltage through a first control signal and a second control signal, adjusting the reference voltage at the corresponding temperature to the target reference voltage, and obtaining the driving voltage at the corresponding temperature as the target driving voltage for the corresponding temperature; based on the mapping relationship between different temperatures and the corresponding target driving voltages, establishing a temperature test calibration table and storing the temperature test calibration table in a storage unit.

[0069] Specifically, by placing the Hall sensor temperature compensation circuit at a preset reference temperature, such as 25°C, a reference voltage at the reference temperature is obtained, and the reference voltage at the reference temperature is used as the target reference voltage. The preset temperature range is [-45°C to 125°C]. The reference voltage at different temperatures is adjusted to the target reference voltage through the first control signal Signal_1 and the second control signal Signal_2 to obtain the target driving voltage at the corresponding temperature, which is used as the target driving voltage at the corresponding temperature. A temperature test calibration table is constructed based on the mapping relationship between different temperatures and the target driving voltage at the corresponding temperature, and the temperature test calibration table is stored in the storage unit in the control module.

[0070] More specifically, the adjustment steps of the Hall sensor temperature compensation method include: obtaining the real-time temperature of the Hall sensor temperature compensation circuit based on the sampling voltage, and obtaining the target driving voltage at the real-time temperature based on the temperature test calibration table; obtaining the real-time voltage of the driving voltage based on the feedback voltage, and controlling the level of the first control signal and the level of the second control signal according to the real-time voltage of the driving voltage and the target driving voltage; adjusting the real-time voltage of the driving voltage by increasing or decreasing it through the first control signal and the second control signal until the real-time voltage of the driving voltage is equal to the target driving voltage, so that the reference voltage at the real-time temperature is stabilized as the target reference voltage.

[0071] It should be noted that the adjustment method includes: converting the real-time temperature into an electrical signal using a thermistor in the sampling module to obtain a sampling voltage; performing analog-to-digital conversion on the sampling voltage using an analog-to-digital converter to obtain the real-time temperature at which the Hall sensor temperature compensation circuit operates; obtaining the target driving voltage at the real-time temperature according to a temperature test calibration table; performing analog-to-digital conversion on the feedback voltage and inputting it into the arithmetic unit to obtain the real-time driving voltage; controlling the levels of a first control signal and a second control signal based on the relationship between the real-time driving voltage and the target driving voltage; adjusting the real-time driving voltage using the first and second control signals until the real-time driving voltage equals the target driving voltage corresponding to the real-time temperature, indicating that the reference voltage has stabilized at the target reference voltage, thus completing the temperature compensation for the Hall sensor.

[0072] This application provides a Hall sensor temperature compensation circuit and method. The circuit includes a sampling module, a control module, a compensation module, and a drive amplification module. The sampling module converts temperature into a voltage signal through a thermistor to obtain a sampling voltage. The control module generates a first control signal and a second control signal based on the sampling voltage and the feedback voltage. The compensation module adjusts the drive voltage of the Hall sensor according to the first and second control signals to adjust the drive voltage to the target drive voltage at the corresponding temperature and samples the drive voltage to obtain a feedback voltage. The drive amplification module drives the Hall sensor with the target drive voltage at the corresponding temperature and amplifies the output voltage of the Hall sensor to stabilize the reference voltage at the corresponding temperature as the target reference voltage. This application converts temperature into a signal, obtains the target drive voltage at the corresponding temperature through sampling voltage, and adjusts the drive voltage of the Hall sensor to the target drive voltage at the corresponding temperature. This ensures that the reference voltage output by the Hall sensor is not affected by temperature. The circuit structure is simple, facilitates rapid adjustment of temperature compensation for the Hall sensor, has a wide range of applications, can be used in low-power portable sensors, ensures high-precision temperature compensation, and has high reliability.

[0073] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A Hall sensor temperature compensation circuit, characterized in that, include: The sampling module samples the temperature using a thermistor to obtain the sampling voltage; The control module is connected to the sampling voltage and the feedback voltage, and generates a first control signal and a second control signal based on the sampling voltage and the feedback voltage. The compensation module is connected to the first control signal and the second control signal. It compensates and adjusts the driving voltage of the Hall sensor according to the first control signal and the second control signal, and samples the driving voltage to obtain the feedback voltage. The drive amplification module is connected to the drive voltage. It drives the Hall sensor through the drive voltage and amplifies the output voltage of the Hall sensor to obtain the reference voltage. The compensation module adjusts the driving voltage to the target driving voltage at the corresponding temperature according to the first control signal and the second control signal, so that the reference voltage at the corresponding temperature is stabilized as the target reference voltage. The compensation module includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first diode, a second diode, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, and a first operational amplifier. The cathode of the first diode is connected to the inverting input of the first operational amplifier via the second resistor in series. The cathode of the first diode is also connected to the anode of the second diode. The inverting input of the first operational amplifier is grounded via the third capacitor in series. The inverting input of the first operational amplifier is also connected to the output of the first operational amplifier via the fifth capacitor in series. One end of the third resistor is connected to the second power supply voltage, and the other end of the third resistor is connected to the second power supply voltage via the second resistor in series. The fourth resistor is grounded, the other end of the third resistor is connected to the non-inverting input of the first operational amplifier, the other end of the third resistor is also grounded through the fourth capacitor connected in series, the ground terminal of the first operational amplifier is grounded, the power supply terminal of the first operational amplifier is connected to the second power supply voltage, the power supply terminal of the first operational amplifier is also grounded through the sixth capacitor connected in series, the output terminal of the first operational amplifier is also grounded through the fifth resistor and the seventh capacitor connected in series, wherein the anode of the first diode is connected to the first control signal, the cathode of the second diode is connected to the second control signal, the output terminal of the first operational amplifier outputs the driving voltage, and the common terminal of the fifth resistor and the seventh capacitor outputs the feedback voltage.

2. The Hall sensor temperature compensation circuit according to claim 1, characterized in that, The sampling module includes a thermistor, a first resistor, a first capacitor, and a second capacitor. One end of the first resistor is connected to the first power supply voltage, and the other end of the first resistor is grounded after passing through the thermistor connected in series. One end of the first capacitor is connected to the first power supply voltage, and the other end of the first capacitor is grounded. One end of the second capacitor is connected to the other end of the first resistor, and the other end of the second capacitor is grounded. The other end of the first resistor outputs the sampling voltage.

3. The Hall sensor temperature compensation circuit according to claim 1, characterized in that, The drive amplifier module includes a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, and a second operational amplifier. One end of the sixth resistor is connected to the second power supply voltage, and the other end of the sixth resistor is connected to one end of the seventh resistor. The other end of the sixth resistor is also connected to the power supply terminal of the Hall sensor. The ground terminal of the Hall sensor is grounded through the eighth resistor connected in series. The first output terminal of the Hall sensor is grounded through the eighth capacitor connected in series. The first output terminal of the Hall sensor is also connected to the inverting input terminal of the second operational amplifier through the ninth resistor connected in series. The inverting input terminal of the second operational amplifier is also connected to the output terminal of the second operational amplifier through the thirteenth resistor connected in series. The tenth capacitor and the thirteenth capacitor... The resistors are connected in parallel. The second output terminal of the Hall sensor is grounded after passing through the ninth capacitor in series. The second output terminal of the Hall sensor is also connected in series with the tenth resistor, which is then connected to the non-inverting input terminal of the second operational amplifier. One end of the eleventh resistor is connected to the second power supply voltage, and the other end of the eleventh resistor is grounded after passing through the twelfth resistor in series. The other end of the eleventh resistor is also connected to the non-inverting input terminal of the second operational amplifier. The power supply terminal of the second operational amplifier is connected to the second power supply voltage. The power supply terminal of the second operational amplifier is also grounded after passing through the twelfth capacitor in series. One end of the eleventh capacitor is connected to the non-inverting input terminal of the second operational amplifier, and the other end of the eleventh capacitor is connected to the ground terminal of the second operational amplifier. The ground terminal of the second operational amplifier is grounded. The other end of the seventh resistor is connected to the driving voltage. The output terminal of the second operational amplifier outputs the reference voltage.

4. The Hall sensor temperature compensation circuit according to claim 1, characterized in that, The control module includes an analog-to-digital conversion unit, an arithmetic unit, and a storage unit. The analog-to-digital conversion unit performs analog-to-digital conversion on the sampled voltage to obtain the real-time temperature. The storage unit stores a temperature test calibration table, which consists of the mapping relationship between different temperatures and the target driving voltage at the corresponding temperature.

5. The Hall sensor temperature compensation circuit according to claim 4, characterized in that, The arithmetic unit acquires the real-time temperature and obtains the target driving voltage under the real-time temperature according to the temperature test calibration table. Based on the feedback voltage, it obtains the real-time driving voltage and adjusts the real-time driving voltage to the target driving voltage through the first control signal and the second control signal.

6. A method for temperature compensation of a Hall sensor, characterized in that, The circuit applied to the Hall sensor temperature compensation circuit as described in claims 1-5 includes: The temperature is sampled by the sampling module to obtain the sampling voltage; The control module generates a first control signal and a second control signal based on the sampled voltage and the feedback voltage; The compensation module adjusts the driving voltage according to the first control signal and the second control signal to adjust the driving voltage to the target driving voltage at the corresponding temperature, and samples the driving voltage to obtain the feedback voltage. The drive amplification module drives the Hall sensor with the adjusted drive voltage and amplifies the output voltage of the Hall sensor to stabilize the reference voltage at the corresponding temperature as the target reference voltage.

7. The Hall sensor temperature compensation method according to claim 6, characterized in that, Hall sensor temperature compensation methods also include: The temperature of the Hall sensor temperature compensation circuit is adjusted to the reference temperature, and the reference voltage at the reference temperature is obtained as the target reference voltage. Within a preset temperature range, the temperature of the Hall sensor temperature compensation circuit is adjusted according to a preset step. The driving voltage is adjusted through the first control signal and the second control signal to adjust the reference voltage at the corresponding temperature to the target reference voltage, and the driving voltage at the corresponding temperature is obtained as the target driving voltage at the corresponding temperature. Based on the mapping relationship between different temperatures and their corresponding target driving voltages, a temperature test calibration table is established and stored in the storage unit.

8. The Hall sensor temperature compensation method according to claim 7, characterized in that, The adjustment steps for the Hall sensor temperature compensation method include: The real-time temperature of the Hall sensor temperature compensation circuit is obtained based on the sampling voltage, and the target driving voltage at the real-time temperature is obtained based on the temperature test calibration table. The real-time voltage of the driving voltage is obtained based on the feedback voltage, and the level of the first control signal and the level of the second control signal are controlled according to the real-time voltage of the driving voltage and the target driving voltage. The real-time voltage of the driving voltage is increased or decreased by the first control signal and the second control signal until the real-time voltage of the driving voltage is equal to the target driving voltage, so that the reference voltage at the real-time temperature is stabilized as the target reference voltage.

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