Magnetic sensing chip sensitivity temperature excursion testing device and testing method

Abstract

The invention relates to the field of magnetic sensing chip detection, and provides a magnetic sensing chip sensitivity temperature excursion testing device and a testing method. The device comprises an incubator, a temperature excursion test module and a signal acquisition module, the temperature excursion test module is arranged in the incubator, and the signal acquisition module is connected with the temperature excursion test module; the temperature drift test module comprises m magnetic field generation modules, each magnetic field generation module comprises a permanent magnet clamping seat and a plurality of permanent magnets, the permanent magnet clamping seat is provided with a through hole for accommodating a to-be-tested magnetic sensing chip and a standard magnetic sensing chip, and the plurality of permanent magnets are arranged in the permanent magnet clamping seat at two sides of the through hole; and the signal acquisition module is provided with m channels and is used for simultaneously acquiring output signals of the to-be-tested magnetic sensing chips corresponding to the m magnetic field generation modules and the standard magnetic sensing chip. According to the invention, the sensitivity temperature excursion test of the linear magneto-sensitive sensing chip can be realized with low cost and high efficiency.

Description

Technical Field

[0001] The invention relates to the field of magnetic sensor chip detection, and in particular to a magnetic sensor chip sensitivity temperature drift test device and a magnetic sensor chip sensitivity temperature drift test method. Background Art

[0002] Linear magnetic sensor chips such as Hall chips and tunnel magnetoresistive chips can indirectly measure various physical quantities such as position, angle and current by measuring magnetic fields. They are widely used in electric vehicles, photovoltaic inverters, industrial control and smart instruments. The magnetic field sensitive part of the Hall chip is generally made of semiconductor materials, and its magnetic field measurement principle is based on the Hall effect of semiconductor materials. When the temperature changes, the physical parameters of the semiconductor material such as conductivity and carrier mobility will change, which will affect the intensity of the Hall effect and cause the magnetic field sensitivity of the Hall chip to drift with temperature. The physical properties of the sensitive materials in the tunnel magnetoresistive chip will also be affected by temperature changes, which will affect the resistance state of the magnetic tunnel junction, resulting in temperature drift of the tunnel magnetoresistive effect. In addition, chip packaging and manufacturing processes will also introduce additional temperature dependence to the magnetic sensor chip.

[0003] In engineering applications, sensitivity temperature drift is one of the important factors that limit the actual performance of magnetic sensor chips such as Hall chips and tunnel magnetoresistive chips. Its influence can be reduced by temperature drift compensation methods. When compensating for temperature drift, it is first necessary to test the sensitivity temperature drift characteristics of the magnetic sensor chip to obtain the temperature drift curve and temperature drift coefficient. The commonly used method is to use a coil to generate a test magnetic field, and then place the coil and the test sample in a high and low temperature box to realize the sensitivity temperature drift test. Due to the large volume and weight of the coil, a temperature box with a large internal space is required, and the load-bearing capacity of the internal structure of the temperature box is required to be high. In addition, when the coil is working, a large current needs to be passed to generate a magnetic field of sufficient strength, so that the coil itself generates a lot of heat. When tested at high temperatures (such as 125℃~150℃), the heat inside the coil is not easy to dissipate, and it will continue to accumulate, and it is impossible to continuously output the magnetic field for a long time. The existing sensitivity temperature drift test device is limited by the size of the internal space of the temperature box, and the volume of the coil cannot be too large; during high temperature testing, the heat accumulation problem makes the current of the coil not too large. Due to the limitation of coil volume and current, the magnetic field strength generated by the coil under high temperature test will not be very large, and the effective duration of high temperature test cannot be too long, which makes it impossible to directly test the sensitivity temperature drift of the magnetic sensor chip with a large range. The sensitivity temperature drift characteristics of the large range can only be indirectly inferred through the test results of the sensitivity temperature drift of a relatively small range. However, the temperature drift characteristics under the large range and the small range are not necessarily completely consistent, and this indirect inference method has deviations. Summary of the invention

[0004] In order to solve the above technical defects, the present invention provides a magnetic sensor chip sensitivity temperature drift test device and test method.

[0005] The present invention provides a magnetic sensor chip sensitivity temperature drift test device, comprising: a temperature box, a temperature drift test module and a signal acquisition module, wherein the temperature in the temperature box is adjustable, the temperature drift test module is arranged in the temperature box, and the signal acquisition module is connected to the temperature drift test module;

[0006] The temperature drift test module includes m magnetic field generating modules, each of which includes a permanent magnet holder and a plurality of permanent magnets, the permanent magnet holder is provided with a through hole for accommodating a magnetic sensor chip to be tested and a standard magnetic sensor chip, and a plurality of permanent magnets are placed in the permanent magnet holder on both sides of the through hole;

[0007] The signal acquisition module has m channels for simultaneously acquiring output signals of the magnetic sensor chips to be tested and the standard magnetic sensor chips corresponding to the m magnetic field generating modules, wherein m is a positive integer greater than or equal to 1.

[0008] In the embodiment of the present invention, the through hole of the permanent magnet holder of each magnetic field generating module can accommodate at least one magnetic sensor chip to be tested and one standard magnetic sensor chip;

[0009] The standard magnetic sensor chip is a calibrated and calibrated magnetic sensor chip.

[0010] In the embodiment of the present invention, the connection line formed by the plurality of permanent magnets passes through the magnetic sensitive area of ​​the magnetic sensor chip in the through hole of the permanent magnet holder.

[0011] In the embodiment of the present invention, the magnetization direction of the permanent magnet is perpendicular to the plane of the permanent magnet holder.

[0012] In the embodiment of the present invention, the permanent magnet holder is provided with a plurality of permanent magnet slots, and the plurality of permanent magnets are respectively placed in the plurality of permanent magnet slots.

[0013] In the embodiment of the present invention, the shape of the permanent magnet is round or square, and the shape of the permanent magnet slot matches the shape of the permanent magnet.

[0014] In the embodiment of the present invention, the material of the permanent magnet is a permanent magnet material with a low temperature coefficient, and the absolute value of the temperature coefficient of the material of the permanent magnet does not exceed 0.05% / °C.

[0015] In an embodiment of the present invention, the temperature drift test module further includes: a circuit board;

[0016] The circuit board is provided with a plurality of chip bases for mounting magnetic sensor chips;

[0017] The chip base corresponds to the through hole of the permanent magnet holder, so that the magnetic sensor chip on the chip base is located in the through hole.

[0018] In the embodiment of the present invention, a signal interface is provided on the circuit board;

[0019] The signal interface has a plurality of pins corresponding to a plurality of channels of the signal acquisition module, and the output pins of the chip base are connected to the pins of the signal interface.

[0020] In the embodiment of the present invention, a power interface is provided on the circuit board, and the power interface is connected to the power supply outside the incubator; and the power pin of the chip base is connected to the power interface.

[0021] In the embodiment of the present invention, the magnetic field generating module is fixed on the circuit board through a first stud.

[0022] In the embodiment of the present invention, the circuit board is fixed to the support plate in the temperature box by means of second studs.

[0023] Another aspect of the present invention provides a method for testing the temperature drift of the sensitivity of a magnetic sensor chip. The method is based on the above-mentioned device for testing the temperature drift of the sensitivity of a magnetic sensor chip. The method comprises:

[0024] A reasonable number of permanent magnets are placed in the permanent magnet holder, so that the areas where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located in the through hole of the permanent magnet holder are in a full magnet state; the target temperatures of the temperature box are set to the reference temperature, the low temperature point temperature, and the high temperature point temperature, respectively, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, and the output voltage value of the magnetic sensor chip to be tested and the output voltage value of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module are recorded;

[0025] The permanent magnet in the permanent magnet holder is taken out, so that the area where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located in the through hole of the permanent magnet holder is in a zero magnetic state; the target temperature of the temperature box is set to the reference temperature, the low temperature point temperature, and the high temperature point temperature respectively, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, and the output voltage value of the magnetic sensor chip to be tested and the output voltage value of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module are recorded;

[0026] The sensitivity temperature drift of the magnetic sensor chip to be tested is calculated according to the output voltage values ​​of the magnetic sensor chip to be tested and the standard magnetic sensor chip in the test environment of the reference temperature, the low temperature point temperature and the high temperature point temperature.

[0027] In the embodiment of the present invention, after setting the target temperature of the incubator to the reference temperature, the low temperature point temperature or the high temperature point temperature, the incubator waits for at least 10 minutes after reaching the set temperature so that the magnetic sensor chip to be tested and the standard magnetic sensor chip can reach a thermal equilibrium state with the inside of the incubator.

[0028] In the embodiment of the present invention, the sensitivity temperature drift of the magnetic sensor chip to be tested is calculated according to the output voltage values ​​of the magnetic sensor chip to be tested and the standard magnetic sensor chip in the test environment of the reference temperature, the low temperature point temperature and the high temperature point temperature, including:

[0029] Assume that the reference temperature is T1, the low temperature point temperature is T2, and the high temperature point temperature is T3. In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the sensitivity of the magnetic sensor chip to be tested is K1, K2, and K3 respectively, and the sensitivity of the standard magnetic sensor chip is K';

[0030] In the fully magnetic state, in the environments of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the output voltage values ​​of the magnetic sensor chip to be tested are U1, U2, and U3 respectively, and the output voltage values ​​of the standard magnetic sensor chip are U1', U2', and U3' respectively;

[0031] In the zero magnetic state, in the environments of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the output voltage values ​​of the magnetic sensor chip to be tested are V1, V2, and V3 respectively, and the output voltage values ​​of the standard magnetic sensor chip are V1', V2', and V3' respectively;

[0032] In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the magnetic field difference between the full magnetic field and the zero magnetic field generated by the magnetic field generating module is ΔB1, ΔB2, and ΔB3 respectively, then:

[0033]

[0034] In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the sensitivities K1, K2, and K3 of the magnetic sensor chip to be tested are expressed as:

[0035]

[0036] In the temperature range from the low temperature point T2 to the reference temperature T1, the sensitivity temperature drift coefficient of the magnetic sensor chip to be tested is:

[0037]

[0038] In the temperature range from the reference temperature T1 to the high temperature point temperature T3, the sensitivity temperature drift coefficient of the magnetic sensor chip to be tested is:

[0039]

[0040] The present invention forms a magnetic field generating module through a permanent magnet holder and a plurality of permanent magnets in the permanent magnet holder, and a through hole capable of accommodating a magnetic sensor chip to be tested and a standard magnetic sensor chip is arranged in the permanent magnet holder. By reasonably configuring the number and spacing of the permanent magnets, a high-intensity magnetic field with a wide variation can be generated in a magnetic field sensitive area of ​​the magnetic sensor chip. The magnetic field intensity generated by the low-temperature drift permanent magnet is not affected by the high temperature in the temperature box, the duration of the high-temperature test is not limited, and a wide range of sensitivity temperature drift tests can be performed on the magnetic sensor chip.

[0041] In addition, the volume size of the multiple magnetic field generating modules formed by the permanent magnet holder and the permanent magnet of the present invention is small, and a high-intensity magnetic field can be generated in a small space; the multiple magnetic field generating modules are combined with a multi-channel signal acquisition module to perform sensitivity temperature drift tests on multiple magnetic sensor chips at the same time, thereby improving the test efficiency.

[0042] Other features and advantages of the technical solution of the present invention will be described in detail in the specific implementation section below. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0044] Figure 1 is a block diagram of a magnetic sensor chip sensitivity temperature drift test device provided by an embodiment of the present invention;

[0045] Figure 2 1 is a schematic diagram of the structure of a temperature drift test module of a magnetic sensor chip sensitivity temperature drift test device provided in an embodiment of the present invention (top view);

[0046] Figure 3 1 is a schematic diagram of the structure of a temperature drift test module of a magnetic sensor chip sensitivity temperature drift test device provided in an embodiment of the present invention (side view);

[0047] Figure 4 The figure is a flow chart of a method for testing the temperature drift of sensitivity of a magnetic sensor chip provided by an embodiment of the present invention.

[0048] Description of Reference Numerals

[0049] 1- Temperature box, 2- Temperature drift test module, 3- Signal acquisition module, 4- Host computer, 5- Power supply,

[0050] 6-power interface, 7-signal interface, 8-magnetic field generating module, 9-permanent magnet slot, 10-permanent magnet,

[0051] 11-permanent magnet holder, 12-through hole, 13-chip base, 14-magnetic sensor chip to be tested,

[0052] 15-circuit board, 16-first stud, 17-second stud, 18-support plate,

[0053] 19-Standard magnetic sensor chip. DETAILED DESCRIPTION

[0054] In order to make the technical solutions and advantages of the embodiments of the present invention more clearly understood, the exemplary embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0055] 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" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0056] In the present invention, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] As described in the background technology, the existing sensitivity temperature drift test device is limited by the size of the internal space of the temperature box, and the coil volume cannot be too large; during high-temperature testing, the heat accumulation problem makes the coil current cannot be too large. The limitation of coil volume and current makes the magnetic field intensity generated by the coil under high-temperature testing not very large, and the effective duration of high-temperature testing cannot be too long, resulting in the inability to directly test the sensitivity temperature drift of the magnetic sensor chip with a large range. The sensitivity temperature drift characteristics of the large range can only be indirectly inferred through the sensitivity temperature drift test results of a relatively small range. The temperature drift characteristics under a large range and a small range are not necessarily completely consistent, and this indirect inference method has deviations.

[0058] In view of the above problems, an embodiment of the present invention provides a magnetic sensor chip sensitivity temperature drift test device, including: a temperature box, a temperature drift test module and a signal acquisition module, the temperature in the temperature box is adjustable, the temperature drift test module is arranged in the temperature box, and the signal acquisition module is connected to the temperature drift test module. The temperature drift test module includes m (m≥1) magnetic field generating modules, each magnetic field generating module includes a permanent magnet holder and a plurality of permanent magnets, the permanent magnet holder is provided with a through hole for accommodating a magnetic sensor chip to be tested and a standard magnetic sensor chip, and a plurality of permanent magnets are placed in the permanent magnet holder on both sides of the through hole. The signal acquisition module has m acquisition channels, which are used to simultaneously acquire the output signals of the magnetic sensor chip to be tested and the standard magnetic sensor chip corresponding to the m magnetic field generating modules.

[0059] The present invention forms a magnetic field generating module through a permanent magnet holder and multiple permanent magnets in the permanent magnet holder, and sets a through hole in the permanent magnet holder that can accommodate a magnetic sensor chip to be tested and a standard magnetic sensor chip. By reasonably configuring the number and spacing of the permanent magnets, a high-intensity magnetic field with wide variation can be generated in the magnetic field sensitive area of ​​the magnetic sensor chip. The magnetic field intensity generated by the low-temperature drift permanent magnet is not affected by the high temperature in the temperature box, and the duration of the high-temperature test is not limited, and a large range of sensitivity temperature drift tests can be performed on the magnetic sensor chip. The volume size of the multiple magnetic field generating modules formed by the permanent magnet holder and the permanent magnet of the present invention is small, and a high-intensity magnetic field can be generated in a small space; the multiple magnetic field generating modules are combined with a multi-channel signal acquisition module, and the sensitivity temperature drift test can be performed on multiple magnetic sensor chips at the same time, thereby improving the test efficiency.

[0060] Figure 1 is a block diagram of a magnetic sensor chip sensitivity temperature drift test device provided by an embodiment of the present invention. Figure 1As shown, the magnetic sensor chip sensitivity temperature drift test device provided in this embodiment includes: an incubator 1, a temperature drift test module 2, a signal acquisition module 3, a host computer 4, and a power supply 5. The temperature drift test module 2 is arranged in the test area in the incubator 1, and the signal acquisition module 3, the host computer 4 and the power supply 5 are located outside the incubator 1. The temperature drift test module 2 in the incubator 1 is connected to the signal acquisition module 3 and the power supply 5 respectively, and the signal acquisition module 3 is connected to the host computer 4. The host computer 4 is installed with acquisition software matching the signal acquisition module 3, and can read the acquisition signals of each channel of the signal acquisition module 3.

[0061] like Figure 2 and Figure 3 As shown, the temperature drift test module 2 includes m magnetic field generating modules 8. Each magnetic field generating module 8 includes a permanent magnet holder 11 and a plurality of permanent magnets 10. A through hole 12 is provided at the center of the plane of the permanent magnet holder 11. The through hole 12 can accommodate a magnetic sensor chip 14 to be tested and a standard magnetic sensor chip 19. With the through hole 12 as the center, a plurality of permanent magnet slots 9 are symmetrically provided on the left and right sides of the permanent magnet holder 11. The plurality of permanent magnets 10 are symmetrically placed in the permanent magnet slots 9 on both sides of the through hole 12.

[0062] In this embodiment, the temperature drift test module 2 also includes a circuit board 15, on which a plurality of chip bases 13 for mounting magnetic sensor chips are provided. The chip base 13 corresponds to the through hole 12 of the permanent magnet holder 11, and the magnetic sensor chip 14 to be tested and the standard magnetic sensor chip 19 are fixed on the chip base 13, and the magnetic sensor chip 14 to be tested and the standard magnetic sensor chip 19 pass through the through hole 12 of the permanent magnet holder 11 and are located in the through hole 12. A signal interface 7 and a power interface 6 are also provided on the circuit board 15 of the temperature drift test module 2. The signal interface 7 has a plurality of pins corresponding to a plurality of channels of the signal acquisition module 3, and the output pins of the chip base 13 are connected to the pins of the signal interface 7. The power interface 6 is connected to the power supply 5 outside the temperature box 1, and the power supply 5 pins of the chip base 13 are connected to the power interface 6.

[0063] like Figure 2 and Figure 3 As shown, the magnetic field generating module 8 is fixed to the circuit board 15 by the first stud 16. The circuit board 15 is fixed to the support plate 18 in the incubator 1 by the second stud 17. The chip base 13, the power interface 6 and the signal interface 7 are fixed to the circuit board 15 by welding. The power supply 5 pins of each chip base 13 on the circuit board 15 are respectively connected to the corresponding pins of the power interface 6, and the corresponding pins of the power interface 6 are connected to the output end of the power supply 5. The output signal pins of each chip base 13 are respectively connected to the corresponding pins of each channel of the signal interface 7, and the corresponding pins of each channel of the signal interface 7 are respectively connected to the corresponding pins of each input channel of the signal acquisition module 3. The magnetic sensor chip 14 to be tested and the standard magnetic sensor chip 19 are fixed to the chip base 13 by plugging.

[0064] In this embodiment, according to the number of magnetic sensor chip samples to be tested, the temperature drift test module 2 may include m magnetic sensor chips to be tested 14, m standard magnetic sensor chips 19, 2m chip bases 13 and m magnetic field generating modules 8. Accordingly, the signal acquisition module 3 and the signal interface 7 are configured with m channels, and the output signals of the magnetic sensor chips to be tested 14 and the standard magnetic sensor chips 19 corresponding to the m magnetic field generating modules 8 can be collected simultaneously.

[0065] In this embodiment, the through hole 12 of the permanent magnet holder 11 of each magnetic field generating module 8 can accommodate at least one magnetic sensor chip 14 to be tested and one standard magnetic sensor chip 19. The standard magnetic sensor chip 19 is a calibrated and calibrated magnetic sensor chip, and its sensitivity temperature drift does not exceed 50ppm / °C. The type of the standard magnetic sensor chip 19 is the same as the type of the magnetic sensor chip 14 to be tested, or the type of the standard magnetic sensor chip 19 is different from the type of the magnetic sensor chip 14 to be tested.

[0066] In this embodiment, the material of the permanent magnet 10 is a permanent magnet material with a low temperature coefficient, and the absolute value of the temperature coefficient of the permanent magnet material does not exceed 0.05% / °C, such as Sm2Co17 type samarium cobalt permanent magnet material. The magnetization direction of the permanent magnet 10 is perpendicular to the left and right planes of the permanent magnet holder 11. The connecting line formed by multiple permanent magnets 10 passes through the magnetic sensitive area of ​​the magnetic sensor chip in the through hole 12 of the permanent magnet holder 11. The shape of the permanent magnet 10 is round or square, and the shape of the permanent magnet slot 9 matches the shape of the permanent magnet 10, so that the permanent magnet 10 can be stably inserted into the permanent magnet slot 9.

[0067] In the present embodiment, the left and right plane geometric center lines of each permanent magnet pass through the magnetic sensitive area inside the magnetic sensor chip to be tested and the standard magnetic sensor chip. By adjusting the number of permanent magnets, the placement direction and the spacing of each permanent magnet slot, the magnetic field direction and magnetic field size of the magnetic sensitive area of ​​the magnetic sensor chip to be tested and the standard magnetic sensor chip can be changed. Therefore, by reasonably configuring the number and position of the permanent magnets and the spacing of the permanent magnet slots, a wide-range magnetic field can be generated in the magnetic field sensitive area of ​​the magnetic sensor chip. Further, by controlling the distance of the magnetic sensor chip relative to the permanent magnet, a high-intensity magnetic field can be generated in a small space, and the temperature stability of the low-temperature drift permanent magnet material is combined with a calibrated standard magnetic sensor chip to solve the problem of generating a high-intensity magnetic field under a high-temperature test environment, and it can be ensured that the effective duration of the high-intensity magnetic field test is not affected by high temperature.

[0068] The present invention utilizes low-temperature drift permanent magnets to generate a magnetic field, changes the size of the magnetic field by changing the number and position of the permanent magnets, combines the permanent magnets with a temperature box, and implements a sensitivity temperature drift test of a linear magnetic sensor chip at low cost and high efficiency.

[0069] The embodiment of the present invention also provides a method for testing the temperature drift of the sensitivity of a magnetic sensor chip. The method is based on the above-mentioned device for testing the temperature drift of the sensitivity of a magnetic sensor chip. Figure 4 As shown, the magnetic sensor chip sensitivity temperature drift test method includes the following steps:

[0070] S401, placing a reasonable number of permanent magnets in the permanent magnet holder, so that the areas where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located in the through hole of the permanent magnet holder are in a full magnet state; setting the target temperatures of the temperature box to the reference temperature, the low temperature point temperature, and the high temperature point temperature, respectively, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, and recording the output voltage value of the magnetic sensor chip to be tested and the output voltage value of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module;

[0071] S402, taking out the permanent magnet in the permanent magnet holder, so that the area where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located in the through hole of the permanent magnet holder is in a zero magnetic state; setting the target temperature of the incubator to the reference temperature, the low temperature point temperature, and the high temperature point temperature, respectively, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, and recording the output voltage value of the magnetic sensor chip to be tested and the output voltage value of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module;

[0072] S403, calculating the sensitivity temperature drift of the magnetic sensor chip to be tested according to the output voltage values ​​of the magnetic sensor chip to be tested and the standard magnetic sensor chip in the test environment of the reference temperature, the low temperature point temperature and the high temperature point temperature.

[0073] In one example, the magnetic sensor chip sensitivity temperature drift test method specifically includes the following process:

[0074] (1) According to Figure 1 , Figure 2 and Figure 3 The structure shown in the figure completes the connection and construction of the test device, and turns on the power switches of the temperature box, signal acquisition module, host computer and power supply;

[0075] (2) inserting a corresponding number of magnetic sensor chips and standard magnetic sensor chips into the chip base according to the number of magnetic sensor chip samples to be tested;

[0076] (3) According to the strength of the magnetic field to be tested, the number and placement of the permanent magnets are reasonably determined, and the permanent magnets are stably placed in the permanent magnet slots. At this time, the area where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located is in a full magnetic state;

[0077] (4) Set the target temperature of the incubator to the reference temperature T1 (e.g., 25°C), start the temperature control button, and when the incubator reaches the set temperature, wait for 10 minutes or longer to allow the magnetic sensor chip to reach a thermal equilibrium with the incubator, ensuring that the actual temperature of the magnetic sensor chip to reach the set temperature of the incubator;

[0078] (5) Observe the acquisition software of the host computer and record the full magnetic field output voltage value U1 of the magnetic sensor chip to be tested and the full magnetic field output voltage value U1' of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module;

[0079] (6) Set the target temperature of the incubator to the low temperature point temperature T2 (e.g. -40°C), start the temperature control button, and when the incubator reaches the set temperature, wait for 10 minutes or longer to allow the magnetic sensor chip to be tested and the inside of the incubator to reach a thermal equilibrium state;

[0080] (7) Observe the acquisition software of the host computer and record the full magnetic field output voltage value U2 of the magnetic sensor chip to be tested and the full magnetic field output voltage value U2' of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module;

[0081] (8) Set the target temperature of the incubator to the high temperature point temperature T3 (e.g., 125°C), start the temperature control button, and when the incubator reaches the set temperature, wait for 10 minutes or longer to allow the magnetic sensor chip to be tested and the inside of the incubator to reach a thermal equilibrium state;

[0082] (9) Observe the acquisition software of the host computer and record the full magnetic field output voltage value U3 of the magnetic sensor chip to be tested and the full magnetic field output voltage value U3' of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module;

[0083] (10) Set the target temperature of the incubator to 25°C, start the temperature control button, and open the incubator when it reaches the set temperature. Take out all the permanent magnets in the permanent magnet holder. At this time, the area where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located is in a zero magnetic state;

[0084] (11) Similar to the above operation, the target temperatures of the incubator are respectively set to the reference temperature T1, the low temperature point temperature T2, and the high temperature point temperature T3; the zero magnetic field output voltage values ​​V1, V2, and V3 of the magnetic sensor chip to be tested corresponding to each channel of the signal acquisition module are recorded when the temperatures are the reference temperature T1, the low temperature point temperature T2, and the high temperature point temperature T3; the zero magnetic field output voltage values ​​V1', V2', and V3' of the standard magnetic sensor chip corresponding to each channel of the signal acquisition module are recorded when the temperatures are the reference temperature T1, the low temperature point temperature T2, and the high temperature point temperature T3;

[0085] (12) Assuming that the reference temperature is T1, the low temperature point temperature is T2, and the high temperature point temperature is T3, in the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the sensitivities of the magnetic sensor chip to be tested are K1, K2, and K3 respectively, and the sensitivity of the standard magnetic sensor chip is K';

[0086] In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the magnetic field difference between the full magnetic field and the zero magnetic field generated by the magnetic field generating module is ΔB1, ΔB2, and ΔB3 respectively, then:

[0087]

[0088] In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the sensitivities K1, K2, and K3 of the magnetic sensor chip to be tested are expressed as:

[0089]

[0090] In the temperature range from the low temperature point T2 to the reference temperature T1 (e.g. -40°C to 25°C), the sensitivity temperature drift coefficient of the magnetic sensor chip to be tested is:

[0091]

[0092] In the temperature range from the reference temperature T1 to the high temperature point temperature T3 (e.g. 25°C to 125°C), the sensitivity temperature drift coefficient of the magnetic sensor chip to be tested is:

[0093]

[0094] Thus, the sensitivity temperature drift of the magnetic sensor chip to be tested can be obtained.

[0095] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present invention may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0096] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0097] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0098] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0099] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if 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 also intended to include these modifications and variations.

Claims

1. A magnetic sensor chip sensitivity temperature drift test device, characterized in that: include: A temperature box, a temperature drift test module and a signal acquisition module, wherein the temperature in the temperature box is adjustable, the temperature drift test module is arranged in the temperature box, and the signal acquisition module is connected to the temperature drift test module; The temperature drift test module includes m magnetic field generating modules, each of which includes a permanent magnet holder and a plurality of permanent magnets, the permanent magnet holder is provided with a through hole for accommodating a magnetic sensor chip to be tested and a standard magnetic sensor chip, and a plurality of permanent magnets are placed in the permanent magnet holder on both sides of the through hole; The signal acquisition module has m channels for simultaneously acquiring output signals of the magnetic sensor chips to be tested and the standard magnetic sensor chips corresponding to the m magnetic field generating modules, wherein m is a positive integer greater than or equal to 1.

2. The magnetic sensor chip sensitivity temperature drift test device according to claim 1, characterized in that: The through hole of the permanent magnet holder of each magnetic field generating module can accommodate at least one magnetic sensor chip to be tested and one standard magnetic sensor chip; The standard magnetic sensor chip is a calibrated and calibrated magnetic sensor chip.

3. The magnetic sensor chip sensitivity temperature drift test device according to claim 2, characterized in that: The connection line formed by the plurality of permanent magnets passes through the magnetic sensitive area of ​​the magnetic sensor chip in the through hole of the permanent magnet holder.

4. The magnetic sensor chip sensitivity temperature drift test device according to claim 2, characterized in that: The magnetization direction of the permanent magnet is perpendicular to the plane of the permanent magnet holder.

5. The magnetic sensor chip sensitivity temperature drift test device according to claim 2, characterized in that: The permanent magnet holder is provided with a plurality of permanent magnet slots, and a plurality of permanent magnets are respectively placed in the plurality of permanent magnet slots.

6. The magnetic sensor chip sensitivity temperature drift test device according to claim 5, characterized in that: The shape of the permanent magnet is round or square, and the shape of the permanent magnet slot matches the shape of the permanent magnet.

7. The magnetic sensor chip sensitivity temperature drift test device according to claim 1, characterized in that: The material of the permanent magnet is a permanent magnet material with a low temperature coefficient, and the absolute value of the temperature coefficient of the material of the permanent magnet does not exceed 0.05% / °C.

8. The magnetic sensor chip sensitivity temperature drift test device according to claim 1, characterized in that: The temperature drift test module further includes: a circuit board; The circuit board is provided with a plurality of chip bases for mounting magnetic sensor chips; The chip base corresponds to the through hole of the permanent magnet holder, so that the magnetic sensor chip on the chip base is located in the through hole.

9. The magnetic sensor chip sensitivity temperature drift test device according to claim 8, characterized in that: The circuit board is provided with a signal interface; The signal interface has a plurality of pins corresponding to a plurality of channels of the signal acquisition module, and the output pins of the chip base are connected to the pins of the signal interface.

10. The magnetic sensor chip sensitivity temperature drift test device according to claim 8, characterized in that: The circuit board is provided with a power interface, and the power interface is connected to a power source outside the incubator; The power pin of the chip base is connected to the power interface.

11. The magnetic sensor chip sensitivity temperature drift test device according to claim 8, characterized in that: The magnetic field generating module is fixed on the circuit board through a first stud.

12. The magnetic sensor chip sensitivity temperature drift test device according to claim 8, characterized in that: The circuit board is fixed to the support plate in the temperature box through the second screw.

13. A method for testing the temperature drift of sensitivity of a magnetic sensor chip, characterized in that: The method is based on the magnetic sensor chip sensitivity temperature drift test device according to claim 1, and the method comprises: A reasonable number of permanent magnets are placed in the permanent magnet holder, so that the areas where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located in the through hole of the permanent magnet holder are in a full magnet state; the target temperatures of the temperature box are set to the reference temperature, the low temperature point temperature, and the high temperature point temperature, respectively, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, and the output voltage value of the magnetic sensor chip to be tested and the output voltage value of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module are recorded; The permanent magnet in the permanent magnet holder is taken out, so that the area where the magnetic sensor chip to be tested and the standard magnetic sensor chip are located in the through hole of the permanent magnet holder is in a zero magnetic state; the target temperature of the temperature box is set to the reference temperature, the low temperature point temperature, and the high temperature point temperature respectively, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, and the output voltage value of the magnetic sensor chip to be tested and the output voltage value of the standard magnetic sensor chip corresponding to each acquisition channel of the signal acquisition module are recorded; The sensitivity temperature drift of the magnetic sensor chip to be tested is calculated according to the output voltage values ​​of the magnetic sensor chip to be tested and the standard magnetic sensor chip in the test environment of the reference temperature, the low temperature point temperature and the high temperature point temperature.

14. The method for testing the sensitivity temperature drift of a magnetic sensor chip according to claim 13, characterized in that: The target temperatures of the temperature boxes are respectively set to be the reference temperature, the low temperature point temperature, and the high temperature point temperature, so that the magnetic sensor chip to be tested and the standard magnetic sensor chip are in a test environment of the reference temperature, the low temperature point temperature, and the high temperature point temperature, including: After setting the target temperature of the incubator to the reference temperature, the low temperature point temperature or the high temperature point temperature, wait for at least 10 minutes after the incubator reaches the set temperature to allow the magnetic sensor chip to be tested and the standard magnetic sensor chip to reach thermal equilibrium with the inside of the incubator.

15. The method for testing the sensitivity temperature drift of a magnetic sensor chip according to claim 13, characterized in that: The method of calculating the sensitivity temperature drift of the magnetic sensor chip to be tested according to the output voltage values ​​of the magnetic sensor chip to be tested and the standard magnetic sensor chip in the test environment of the reference temperature, the low temperature point temperature and the high temperature point temperature comprises: Assume that the reference temperature is T1, the low temperature point temperature is T2, and the high temperature point temperature is T3. In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the sensitivity of the magnetic sensor chip to be tested is K1, K2, and K3 respectively, and the sensitivity of the standard magnetic sensor chip is K'; In the fully magnetic state, in the environments of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the output voltage values ​​of the magnetic sensor chip to be tested are U1, U2, and U3 respectively, and the output voltage values ​​of the standard magnetic sensor chip are U1', U2', and U3' respectively; In the zero magnetic state, in the environments of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the output voltage values ​​of the magnetic sensor chip to be tested are V1, V2, and V3 respectively, and the output voltage values ​​of the standard magnetic sensor chip are V1', V2', and V3' respectively; In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the magnetic field difference between the full magnetic field and the zero magnetic field generated by the magnetic field generating module is ΔB1, ΔB2, and ΔB3 respectively, then: In the environment of reference temperature T1, low temperature point temperature T2, and high temperature point temperature T3, the sensitivities K1, K2, and K3 of the magnetic sensor chip to be tested are expressed as: In the temperature range from the low temperature point T2 to the reference temperature T1, the sensitivity temperature drift coefficient of the magnetic sensor chip to be tested is: In the temperature range from the reference temperature T1 to the high temperature point temperature T3, the sensitivity temperature drift coefficient of the magnetic sensor chip to be tested is:

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