MCU-Based Magnetic Sensing Chip Testing Device and Testing Method

Abstract

An embodiment of the present invention provides a magnetic sensor chip testing device and a testing method based on an MCU, belonging to the technical field of magnetic sensor chip testing. The device includes: an MCU unit, and a multi-direction unit of the chip under test, a chip power supply unit, a control unit, and a measurement unit connected to the MCU unit. The device increases the sample quantity of the magnetic sensor chip under test, can provide different test directions for multiple magnetic sensor chips under test, realizes the simultaneous testing of multiple different directions of the magnetic sensor chip, reduces the number of times of changing the direction of the magnetic sensor chip and the number of times of changing the coil direction, and at the same time reduces the volume of the testing components, improves the testing efficiency and the integrity of the performance evaluation of the magnetic sensor chip.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic sensor chip testing, and particularly to a magnetic sensor chip testing device based on an MCU and a magnetic sensor chip testing method based on an MCU. Background Art

[0002] In actual use, the environmental conditions of magnetic sensor chips are relatively complex, and they will be affected by strong magnetic interference in all directions, and magnetic interference in different directions needs to be detected. When external magnetic field interference suddenly occurs during application, how to ensure the sensitivity of magnetic sensor chips in all directions is crucial.

[0003] Currently, magnetic sensor chips are excited by a magnetic field through a magnet or a Helmholtz coil, and a digital multimeter or an oscilloscope is used to test the output state of the magnetic sensor chip. The magnetic field intensity is detected by a gaussmeter, and then the magnetic characteristics of the working point and release point of the magnetic sensor chip are detected.

[0004] However, the existing magnetic sensor chip testing devices are bulky, with complex component structures, and low testing efficiency. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a magnetic sensor chip testing device based on an MCU, which can simultaneously test the working points and release points in multiple different directions of multiple magnetic sensor chips to be tested, effectively improving the testing efficiency.

[0006] To achieve the above purpose, the embodiments of the present invention provide a magnetic sensor chip testing device based on an MCU, which includes: an MCU unit, and a multi-direction unit of the chip to be tested, a chip power supply unit, a control unit, and a measurement unit connected to the MCU unit;

[0007] The multi-direction unit of the chip to be tested is used to fix a first preset number of magnetic sensor chips to be tested and provide different test directions for the magnetic sensor chips to be tested;

[0008] The chip power supply unit is used to provide an adjustable voltage for the magnetic sensor chips to be tested;

[0009] The control unit is used to control the magnetic field intensity and magnetic field direction during testing according to the test control instruction of the MCU unit;

[0010] The measurement unit is used to measure the measurement data of the magnetic sensor chips to be tested at different magnetic field intensities and different magnetic field directions under a preset working voltage during the testing process; wherein, the measurement data includes: the actual measured working point and the actual measured release point;

[0011] The MCU unit is used to determine the detection results of each magnetic sensing chip under test at different magnetic field strengths and different magnetic field directions according to preset test parameters and the measurement data.

[0012] Optionally, the device further includes: a parameter setting unit; the parameter setting unit is used to set test parameters; wherein, the test parameters include: operating point, release point, operating voltage, magnetic field increasing step, magnetic field decreasing step, and step angle.

[0013] Optionally, the device further includes: an output unit and a display unit; the output unit is used to output the detection results to the display unit; the display unit is used to display the test parameters currently set by the parameter setting unit, and is used to display the detection results according to a preset rule.

[0014] Optionally, the multi-direction unit of the chip under test includes three mutually perpendicular PCB boards; a second preset number of magnetic sensing chips under test can be fixed on each PCB board.

[0015] Optionally, the measurement unit includes: a chip output level acquisition circuit; one end of the chip output level acquisition circuit is connected to the magnetic sensing chip under test, and the other end is connected to a digital multimeter; the chip output level acquisition circuit is also connected to the MCU unit; the MCU unit is respectively connected to the digital multimeter and a gaussmeter.

[0016] Optionally, the measurement unit further includes: a current measurement channel control circuit and a resistance measurement channel control circuit;

[0017] One end of the current measurement channel control circuit is connected to the magnetic sensing chip under test through a multiplexer switch, and the other end is connected to a digital multimeter; the current measurement channel control circuit is also connected to the MCU unit;

[0018] One end of the resistance measurement channel control circuit is connected to the magnetic sensing chip under test through a multiplexer switch, and the other end is connected to a digital multimeter; the resistance measurement channel control circuit is also connected to the MCU unit.

[0019] Optionally, the control unit includes: a magnetic field excitation control module; the magnetic field excitation control module is connected to a Helmholtz coil and is used to control the magnetic field strength at which the magnetic sensing chip under test is located during the test with a preset magnetic field increasing step or magnetic field decreasing step.

[0020] Optionally, the control unit further includes: an angle control module; the angle control module is connected to a stepping motor and is used to control the magnetic field direction at which the magnetic sensing chip under test is located during the test with a preset step angle.

[0021] On the other hand, the present invention provides a method for testing a magnetic sensing chip based on an MCU, which is applied to the magnetic sensing chip testing device based on an MCU. The testing method includes the following steps:

[0022] Step 1) Fix a first preset number of magnetic sensing chips to be tested on the multi-direction unit of the chips to be tested;

[0023] Step 2) Control the chip power supply unit to reach the preset working voltage;

[0024] Step 3) Test the magnetic sensing chips to be tested according to the test control instructions of the MCU unit. During the test, control the magnetic field strength and magnetic field direction when testing the magnetic sensing chips to be tested, and obtain the measurement data of each magnetic sensing chip to be tested under different magnetic field strengths and different magnetic field directions; wherein, the measurement data includes: the actual measured working point and the actual measured release point;

[0025] Step 4) The MCU unit determines the detection results of each magnetic sensing chip to be tested under different magnetic field strengths and different magnetic field directions according to the preset test parameters and the measurement data.

[0026] Optionally, before step 1), it further includes: setting test parameters, where the test parameters include: working point, release point, working voltage, magnetic field increasing step, magnetic field decreasing step, and step angle.

[0027] Optionally, step 3) further includes: testing the working current of each magnetic sensing chip to be tested under the preset working voltage.

[0028] Optionally, in step 3), controlling the magnetic field strength and magnetic field direction when testing the magnetic sensing chips to be tested includes:

[0029] Changing the magnetic field strength of the magnetic sensing chips to be tested with the preset magnetic field increasing step or magnetic field decreasing step;

[0030] Rotating the stepping motor with the preset step angle to change the test angle of the magnetic sensing chips to be tested.

[0031] Compared with the prior art, the above technical solution of the present invention has the following beneficial effects:

[0032] The present application provides a magnetic sensing chip testing device based on an MCU. The device fixes multiple magnetic sensing chips to be tested through the multi-direction unit of the chips to be tested, increases the sample quantity of the magnetic sensing chips to be tested, can provide different test directions for multiple magnetic sensing chips to be tested, realizes the simultaneous testing of multiple different directions of the magnetic sensing chips, reduces the number of times of changing the direction of the magnetic sensing chips and the number of times of changing the direction of the coil, and at the same time reduces the volume of the testing components, improves the testing efficiency and the integrity of the performance evaluation of the magnetic sensing chips.

[0033] Other features and advantages of the embodiments of the present invention will be described in detail in the following specific implementation part. Description of the Drawings

[0034] The drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification. Together with the following specific implementation, they are used to explain the embodiments of the present invention, but do not constitute a limitation to the embodiments of the present invention. In the drawings:

[0035] Figure 1 Schematically shows the overall structural diagram of the MCU-based magnetic sensor chip testing device according to the embodiment of the present application;

[0036] Figure 2 Schematically shows the structural diagram of the measurement unit of the MCU-based magnetic sensor chip testing device according to the embodiment of the present application;

[0037] Figure 3 Schematically shows the structural diagram of the multi-direction unit and the test board of the chip under test of the MCU-based magnetic sensor chip testing device according to the embodiment of the present application;

[0038] Figure 4 Schematically shows the flowchart of the testing method of the magnetic sensor chip according to the embodiment of the present application;

[0039] Figure 5 Schematically shows the flowchart of the testing method of the magnetic sensor chip according to a specific embodiment of the present application.

[0040] Description of the Reference Numerals

[0041] 1 - First PCB board, 2 - Second PCB board, 3 - Third PCB board, 4 - Magnetic sensor chip under test, 5 - Test board. Specific Embodiments

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific embodiments described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0043] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present application, the directional indications are only used to explain the relative positional relationship between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0044] Existing test systems apply different magnetic field excitations in one test direction to the magnetic sensing chip to change the magnetic field intensity. First, the magnetic field intensity is gradually increased to the maximum, and then gradually decreased to the minimum, so as to test the magnetic characteristics of the working point and release point of the magnetic sensing chip. Then, the test direction is changed, mainly including two methods. One is to change the direction of the magnetic sensing chip by rotating the motor turntable, and the other is to change the magnetic field excitation direction by coils in different axial directions. The magnetic characteristics are repeatedly tested to complete the 360° direction detection.

[0045] Applying magnetic field excitation by a magnet is a manual test method. This detection method is relatively easy to operate and is not restricted by space and direction. However, different testers move the magnet at different speeds and have different reactions when observing the output change of the magnetic sensing chip, resulting in different test results, which will lead to low detection efficiency, large errors, and poor repeatability.

[0046] The Helmholtz coil test system applies magnetic field excitation in an automatic test method, that is, the magnetic field intensity at the position of the magnetic sensing chip is changed by controlling the magnitude of the current of the Helmholtz coil through a host computer program. This detection method requires high integration of a computer, Helmholtz coils, digital multimeters, oscilloscopes, multi-axis rotating motor turntables, multi-axis Helmholtz coils, etc. However, its disadvantage is that the overall volume of the system is large, the components are complex, and the cost is high, resulting in unnecessary equipment investment.

[0047] Existing test systems do not analyze the functional indicators of the magnetic sensing chip in multiple aspects, that is, in addition to the functions of the working point and release point of the magnetic sensing chip, the resistance between the chip pins and the ground, the power consumption of the chip, and the working voltage test of the chip are not carried out, and the comparison and analysis of the resistance, current, and voltage tests of multiple chips are lacking.

[0048] Existing test systems change the direction of the magnetic sensing chip through a multi-axis rotating motor turntable, which has one-axis, two-axis, and three-axis rotation methods. The more the number of rotating axes, the larger the volume of the test components, and the fewer the number of chips that can be tested with the same component volume.

[0049] Existing test systems change the magnetic field excitation direction through coils in different axial directions, which have one-axis, two-axis, and three-axis coils. Under the same coil size, the more the number of coils, the smaller the volume of the uniform magnetic field, that is, the smaller the detection area.

[0050] How to optimize the complex test system and improve the magnetic characteristic test efficiency while ensuring the magnetic characteristic test quality is a technical problem to be solved urgently.

[0051] In view of this, the embodiment of the present application designs a magnetic sensing chip test device based on an MCU, which is a simple and convenient automatic test device. The magnetic sensing chip test is completed by controlling a gaussmeter, Helmholtz coils, a digital multimeter, and a stepping motor through the MCU.

[0052] Example 1

[0053] Figure 1 Schematically shows the overall structural diagram of the MCU-based magnetic sensor chip testing device according to an embodiment of the present application. As Figure 1 shown, in an embodiment of the present application, a MCU-based magnetic sensor chip testing device is provided. The device includes: a MCU unit, and a multi-direction unit of the chip under test, a chip power supply unit, a control unit, and a measurement unit connected to the MCU unit.

[0054] The multi-direction unit of the chip under test is used to fix a first preset number of magnetic sensor chips under test, and provide different test directions for the magnetic sensor chips under test.

[0055] Specifically, the first preset number can be 6, that is, the magnetic sensor chip testing device provided in this embodiment can test 6 magnetic sensor chips at a time. The multi-direction unit of the chip under test is used to provide different test directions for the magnetic sensor chips, and can simultaneously provide 5 different directions of the chip under test.

[0056] Figure 3 Schematically shows the structural diagram of the multi-direction unit of the chip under test and the test board of the MCU-based magnetic sensor chip testing device according to an embodiment of the present application. The multi-direction unit of the chip under test includes three mutually perpendicular PCB boards. As Figure 3 shown, the first PCB board 1, the second PCB board 2, and the third PCB board 3 are perpendicular to each other. 2 magnetic sensor chips under test can be fixed on each of the first PCB board 1, the second PCB board 2, and the third PCB board 3.

[0057] Specifically, taking the third PCB board 3 as the rotation plane, 2 magnetic sensor chips under test are placed on the rotation plane (i.e., the third PCB board 3). The Helmholtz coil generates a vector magnetic field. Assuming that the vector magnetic field passes through the rotation plane in the x-axis direction, that is, one test direction; 1 magnetic sensor chip under test is placed normally on the first PCB board 1. Assuming that the vector magnetic field passes through the vertical plane 1 in the y-axis direction, and 1 magnetic sensor chip under test is placed while rotating 45° clockwise, that is, two different test directions; 1 magnetic sensor chip under test is placed normally on the second PCB board 2. Assuming that the vector magnetic field passes through the vertical plane 2 in the z-axis direction, and 1 magnetic sensor chip under test is placed while rotating 45° clockwise, that is, two different test directions. The testing device realizes the working points and release points of five different directions of the magnetic sensor chips can be tested simultaneously, effectively improving the testing efficiency.

[0058] The chip power supply unit is used to provide an adjustable voltage for the magnetic sensor chips under test.

[0059] Specifically, the chip power supply unit can provide adjustable voltage for six magnetic sensing chips under test, so that the output voltage is between 2.5V and 6V. For example, a single-chip microcomputer chip such as N76E003AT20 can be used; a control digital potentiometer chip such as X9C503 can be used; to adjust the resistance value, a step-down chip such as BD9677G can be used. The chip power supply unit is used to adjust the reference voltage so that the output voltage is adjustable between 2.5V and 6V. The chip power supply unit can be configured with an indicator light, and through the indicator light, the user can obtain whether the power supply of the magnetic sensing chip under test is working properly.

[0060] The control unit is used to control the magnetic field strength and magnetic field direction during the test according to the test control instructions of the MCU unit.

[0061] Specifically, as Figure 1 shown, the control unit includes: a magnetic field excitation control module and an angle control module. The magnetic field excitation control module is connected to the Helmholtz coil; the angle control module is connected to the stepper motor. The magnetic field excitation control module is used to control the magnetic field strength at which the magnetic sensing chip under test is located during the test with a preset magnetic field step size, such as 0.1mT, and first increase and then decrease the magnetic field strength to complete the magnetic characteristic test of the working point and release point of the magnetic sensing chip under test. The angle control module is used to control the direction of the chip under test during the test with a preset angle step size, such as 30°, and gradually complete the magnetic characteristic test of the working point and release point of the magnetic sensing chip under test in the 360° direction. In this embodiment, a one-axis rotary motor turntable and a one-axis Helmholtz coil can be used to complete the test, which simplifies the magnetic sensing chip test device.

[0062] The measurement unit is used to measure the measurement data of the magnetic sensing chip under test at different magnetic field strengths and different magnetic field directions under a preset working voltage during the test; wherein, the measurement data includes: the actual measured working point and the actual measured release point.

[0063] Specifically, as Figure 1 shown, the measurement unit is connected to a gaussmeter, a digital multimeter, and a chip output level acquisition circuit, and can test a total of 18 measurement and acquisition channels for 6 magnetic sensing chips. Figure 2 It is a schematic diagram of the measurement part of the magnetic sensing chip. The 12-channel analog switch is automatically switched through the MCU control, and at the same time, the digital multimeter is controlled to test the resistance of the power supply pin of the chip under test to the ground, the resistance of the output pin to the ground, and the working current. When the magnetic field changes, the output levels of the 6 chips under test are monitored simultaneously. When a jump occurs, the magnetic field value of the current gaussmeter is read, so as to complete the magnetic characteristic test of the working point and release point of the chip under test.

[0064] Figure 2Schematically shown is a schematic diagram of the measurement unit structure of an MCU-based magnetic sensor chip testing device according to an embodiment of the present application. Specifically, as Figure 2 shown, the measurement unit includes: a current measurement channel control circuit, a resistance measurement channel control circuit, and a chip output level acquisition circuit.

[0065] Specifically, as Figure 2 shown, one end of the current measurement channel control circuit is connected to the first preset number of magnetic sensor chips to be measured through a multiplexer switch, and the other end is connected to a digital multimeter; the current measurement channel control circuit is also connected to the MCU unit.

[0066] Specifically, as Figure 2 shown, one end of the resistance measurement channel control circuit is connected to the first preset number of magnetic sensor chips to be measured through a multiplexer switch, and the other end is connected to a digital multimeter; the resistance measurement channel control circuit is also connected to the MCU unit.

[0067] In this embodiment, the MCU is used to control the automatic switching of the analog switch to achieve continuous testing of multiple chips, realizing automated testing. This embodiment realizes the functions of measuring the resistance of the magnetic sensor chip pins to the ground and current. The testing device integrates the functions of resistance and current measurement, greatly saving the time spent by the staff in connecting cables.

[0068] Specifically, as Figure 2 shown, one end of the chip output level acquisition circuit is connected to the first preset number of magnetic sensor chips to be measured, and the other end is connected to a digital multimeter; the chip output level acquisition circuit is also connected to the MCU unit; the MCU unit is respectively connected to the digital multimeter and the gaussmeter.

[0069] Specifically, for the single-chip microcomputer MCU, the SCM301L080JGC chip can be selected. In addition to the resistance measurement channel control circuit, the current measurement channel control circuit, and the chip output level acquisition circuit, the work of magnetic field excitation control, angle control, display output, and processing of setting parameters / output results is also completed by this single-chip microcomputer MCU.

[0070] The MCU unit is used to determine the detection results of each magnetic sensor chip to be measured under different magnetic field intensities and different magnetic field directions according to the preset test parameters and the measurement data.

[0071] Specifically, the device further includes: a parameter setting unit; the parameter setting unit is used to set test parameters; wherein, the test parameters include: operating point, release point, operating voltage, magnetic field increasing step, magnetic field decreasing step, and step angle.

[0072] In this embodiment, test parameters such as magnetic field strength and angle step size can be preset in advance, and the test efficiency can be adjusted by modifying the step size. In this embodiment, the working voltage test parameters can also be preset in advance. By setting the typical value, minimum value, and maximum value of the working voltage, it is possible to adapt to testing chips with different working voltage ranges.

[0073] Specifically, the device further includes: an output unit and a display unit; the output unit is used to output the detection result to the display unit; the display unit is used to display the test parameters currently set by the parameter setting unit, and to display the detection result according to a preset rule.

[0074] Specifically, the display unit is controlled by a single-chip microcomputer MCU and includes indicator lights and digital tubes. It mainly displays the test parameters currently set by the test device, and compares the test results of the working points and release points of each chip under test with the pre-set parameter information. If the requirements are met, the indicator light shows green, otherwise it shows red.

[0075] Specifically, the parameter setting / output result part has two function buttons. Function buttons can be used to set and save parameters and start the test. The parameter settings include working points, release points, working voltage, magnetic field strength step size, and angle step size. Function buttons are used to export the test results, and the test results include the power supply resistance to ground, output resistance to ground, working points, release points, working current, etc.

[0076] In this embodiment, a method for automatically controlling magnetic field excitation by MCU and monitoring the outputs of multiple chips is proposed. Thus, the magnetic characteristics of working points and release points are tested according to this method, improving the test accuracy and test efficiency; at the same time, it has functions such as resistance test, current test, voltage regulation, display, and output, reducing repeated wiring and manual testing, and improving the efficiency of performance testing.

[0077] Embodiment 2

[0078] Figure 4 Schematically shows a flowchart of a method for testing a magnetic sensing chip according to an embodiment of the present application. As Figure 4 shown, in an embodiment of the present application, a method for testing a magnetic sensing chip based on MCU is provided, which is applied to the magnetic sensing chip testing device based on MCU described in Embodiment 1. The testing method includes the following steps:

[0079] Step 1) Fix a first preset number of magnetic sensing chips under test to the multi-direction unit of the chips under test.

[0080] Specifically, the multi-direction unit of the chips under test can fix up to six magnetic sensing chips under test at most. The first preset number can be 6, that is, the magnetic sensing chip testing device provided in this embodiment can test 6 magnetic sensing chips at a time.

[0081] Step 2) Control the chip power supply unit to reach the preset working voltage.

[0082] Specifically, the chip power supply unit can provide adjustable voltage for six magnetic sensing chips to be measured, so that the output voltage is between 2.5V and 6V. The preset working voltage is the working voltage set by the parameter setting unit, and the working voltage includes: the minimum working voltage, the typical working voltage, and the maximum working voltage, such as 3.1V, 3.3V, and 3.5V.

[0083] Step 3) Test the magnetic sensing chips to be measured according to the test control instructions of the MCU unit. During the test, control the magnetic field strength and magnetic field direction when the magnetic sensing chips to be measured are tested, and obtain the measurement data of each magnetic sensing chip under different magnetic field strengths and different magnetic field directions; wherein, the measurement data includes: the actual measured operating point and the actual measured release point.

[0084] Specifically, the control part includes magnetic field excitation control and angle control, which are respectively connected to a Helmholtz coil and a stepping motor. The magnetic field excitation control is used to control the magnetic field strength at which the chip to be measured is located during the test with the preset magnetic field step size, and first increase and then decrease the magnetic field strength to complete the magnetic characteristic test of the operating point and release point of the chip to be measured. The angle control is used to control the direction at which the chip to be measured is located during the test with the preset angle step size, and complete the magnetic characteristic test of the operating point and release point of the chip to be measured in the 360° direction.

[0085] Step 4) The MCU unit determines the detection results of each magnetic sensing chip to be measured under different magnetic field strengths and different magnetic field directions according to the preset test parameters and the measurement data.

[0086] Specifically, the preset test parameters are the test parameters set by the parameter setting unit, including the operating point and the release point. The measurement data includes the actual measured operating point and the actual measured release point. The detection results can be obtained by comparing and analyzing the preset test parameters and the actual measurement data.

[0087] Embodiment III

[0088] Figure 5 Schematically shows a flowchart of a method for testing a magnetic sensing chip according to a specific embodiment of the present application. As Figure 5 shown, in an embodiment of the present application, a method for testing a magnetic sensing chip based on an MCU is provided, which is applied to the magnetic sensing chip testing device based on an MCU described in Embodiment I. The method includes the following steps:

[0089] Step 1, Prepare to start the test, and install the magnetic sensing chips to be measured on three mutually perpendicular PCB boards. For example, if there are six magnetic sensing chips, the installation method is as Figure 3As shown, two chips under test are soldered on each PCB board. The Helmholtz coil generates a vector magnetic field. Two magnetic sensor chips under test are placed on the rotating plane (i.e., the third PCB board 3). The Helmholtz coil generates a vector magnetic field. Assume that the vector magnetic field passing through the rotating plane is in the x-axis direction, i.e., one test direction; one chip under test is placed normally on the first PCB board 1. Assume that the vector magnetic field passing through the vertical plane 1 is in the y-axis direction, and at the same time, one chip under test is placed with a 45° clockwise rotation, i.e., two different test directions; one chip under test is placed normally on the second PCB board 2. Assume that the vector magnetic field passing through the vertical plane 2 is in the z-axis direction, and at the same time, one chip under test is placed with a 45° clockwise rotation, i.e., two different test directions; the test device can simultaneously test the working points and release points of the magnetic sensor chips in five different directions. Power on the isolated power supply, Gauss meter, digital multimeter, Helmholtz coil, stepper motor, and test device. Reset the parameters according to the specifications of the magnetic sensor chip under test. Set the working points and release points (i.e., preset working points and preset release points) of the magnetic sensor chip under test for the test device according to the technical requirements of the magnetic sensor chip, such as 6 mT and 0.8 mT. Set the minimum, typical, and maximum working voltages, such as 3.1 V, 3.3 V, and 3.5 V. Set the step size for increasing and decreasing the excitation magnetic field of the Helmholtz coil, such as 0.1 mT. Set the angle step size, such as 30°. Set the number of chips under test to 6.

[0090] Step 2: Click the start test button to start the test. There is no voltage output from the chip power supply unit of the test device, that is, the magnetic sensor chip under test is not powered on. The measurement unit controls the digital multimeter to measure the resistance of the power supply pin of the magnetic sensor chip to the ground and the resistance of the output pin to the ground, which are R01, R11... R0x, R1x respectively.

[0091] Step 3: The test device program controls the chip power supply unit to output a voltage of the typical value 3.3 V.

[0092] Step 4: The test device program controls the magnetic field excitation control module to gradually increase the current of the Helmholtz coil to increase the constant magnetic field intensity. When the measurement unit acquisition circuit monitors that the output pin of the magnetic sensor chip under test changes from high level to low level, the measurement unit reads the current magnetic field intensity of the Gauss meter and records it as T0x; the test device program compares with the pre-set working point. If it is greater than the working point, the indicator light of the display unit outputs a red light, otherwise it outputs a green light.

[0093] Step 5: The test device program controls the measurement unit to control the digital multimeter to measure the working current value of the magnetic sensor chip as Ax.

[0094] Step 6, the test device program records the number of magnetic sensing chips that have been tested. Until the test device program determines that the 6th magnetic sensing chip has completed the test, the magnetic field excitation control unit starts to decrease the current of the Helmholtz coil to reduce the constant magnetic field intensity. The chip output level acquisition circuit of the measurement unit monitors that the x'-th output pin of the magnetic sensing chip under test changes from low level to high level. The test device program controls the measurement unit to read the current magnetic field intensity of the gaussmeter and records it as T0x'. The test device program compares it with the pre-set release point. If it is greater than the release point, the indicator light of the display unit outputs a red light, otherwise it outputs a green light. Thus, the tests at five different direction points are completed.

[0095] Step 7, the test device program controls the angle control module to rotate the stepper motor by a pre-set step angle, such as 30°. Repeat the test of the working point and the release point until the 360° direction test is completed.

[0096] Step 8, the test device program controls the chip power supply unit to output a minimum voltage of 3.1V, and repeats the operations of Step 4 - Step 7.

[0097] Step 9, the test device program controls the chip power supply part to output a maximum voltage of 3.5V, and repeats the operations of Step 4 - Step 7.

[0098] Step 10, after the test is completed, click the result output button, and the parameter setting / result output part outputs the test record.

[0099] A method for testing a magnetic sensing chip based on an MCU proposed in this embodiment increases the sample number of the magnetic sensing chips under test, can provide different test directions for multiple magnetic sensing chips under test, realizes the simultaneous test of multiple different directions of the magnetic sensing chip, reduces the number of times of changing the direction of the magnetic sensing chip and the number of times of changing the coil direction, and at the same time reduces the volume of the test components, improves the test efficiency and the integrity of the performance evaluation of the magnetic sensing chip.

[0100] A method for testing a magnetic sensing chip based on an MCU proposed in this embodiment can complete the test by using a one-axis rotating motor turntable and a one-axis Helmholtz coil, simplifies the magnetic sensing chip test system, and adds the functions of testing the chip resistance, current, and voltage. By increasing the number of directions for simultaneous testing, it improves the test efficiency of the magnetic characteristics of the working point and the release point, and reduces the investment in measuring and monitoring equipment such as digital multimeters and oscilloscopes during the test. It meets the user's need to build a test system based on the existing equipment, enabling automatic and flexible testing of the magnetic sensing chip.

[0101] It should also be noted that the term "comprise", "include" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, commodity or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the phrase "comprising an..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the element.

[0102] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various modifications and changes can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A magnetic sensor chip testing device based on MCU, characterized in that, The device includes: an MCU unit, and a multi-direction unit of the chip under test, a chip power supply unit, a control unit, and a measurement unit connected to the MCU unit; The multi-direction unit of the chip under test is used to fix a first preset number of magnetic sensing chips under test, and provide different test directions for the magnetic sensing chips under test. The multi-direction unit of the chip under test includes a first PCB board, a second PCB board, and a third PCB board that are perpendicular to each other. The third PCB board is a rotating plane. A second preset number of magnetic sensing chips under test can be fixed on each PCB board, and magnetic sensing chips under test with different test directions are fixed on the first PCB board and the second PCB board respectively; The chip power supply unit is used to provide an adjustable voltage for the magnetic sensing chips under test; The control unit is used to control the magnetic field strength and magnetic field direction during the test according to the test control instruction of the MCU unit; The measurement unit is used to measure the measurement data of the magnetic sensing chips under test at different magnetic field strengths and different magnetic field directions under a preset working voltage during the test; wherein, the measurement data includes: the actual measurement working point and the actual measurement release point; The MCU unit is used to determine the detection results of each magnetic sensing chip under test at different magnetic field strengths and different magnetic field directions according to the preset test parameters and the measurement data; The control unit includes: a magnetic field excitation control module and an angle control module; The magnetic field excitation control module is connected to the Helmholtz coil and is used to control the magnetic field strength of the magnetic sensing chip under test during the test with a preset magnetic field increasing step or magnetic field decreasing step; The angle control module is connected to the stepping motor and is used to control the magnetic field direction of the magnetic sensing chip under test during the test with a preset stepping angle.

2. The magnetic sensor chip testing device based on MCU according to claim 1, characterized in that, The device further includes: a parameter setting unit; The parameter setting unit is used to set test parameters; wherein, the test parameters include: working point, release point, working voltage, magnetic field increasing step, magnetic field decreasing step, and stepping angle.

3. The magnetic sensor chip testing device based on MCU according to claim 2, characterized in that, The device further includes: an output unit and a display unit; the output unit is used to output the detection results to the display unit; the display unit is used to display the test parameters currently set by the parameter setting unit, and is used to display the detection results according to a preset rule.

4. The magnetic sensor chip testing device based on MCU according to claim 1, characterized in that, The measurement unit includes: a chip output level acquisition circuit; One end of the chip output level acquisition circuit is connected to the magnetic sensing chip under test, and the other end is connected to a digital multimeter; the chip output level acquisition circuit is also connected to the MCU unit; The MCU unit is respectively connected to the digital multimeter and the gaussmeter.

5. The magnetic sensor chip testing device based on MCU according to claim 4, characterized in that, The measurement unit further includes: a current measurement channel control circuit and a resistance measurement channel control circuit; One end of the current measurement channel control circuit is connected to the magnetic sensing chip under test through a multiplexer switch, and the other end is connected to a digital multimeter; the current measurement channel control circuit is also connected to the MCU unit; One end of the resistance measurement channel control circuit is connected to the magnetic sensing chip under test through a multiplexer switch, and the other end is connected to a digital multimeter; the resistance measurement channel control circuit is also connected to the MCU unit.

6. A magnetic sensor chip testing method based on MCU, characterized in that, Applied to the MCU-based magnetic sensor chip testing device described in any one of claims 1 to 5, the testing method includes the following steps: Step 1): Fix a first preset number of magnetic sensor chips to be tested on the multi-direction unit of the chips to be tested; Step 2): Control the chip power supply unit to reach the preset working voltage; Step 3): Test the magnetic sensor chips to be tested according to the test control instructions of the MCU unit. During the test, control the magnetic field intensity and magnetic field direction when testing the magnetic sensor chips to be tested, and obtain the measurement data of each magnetic sensor chip to be tested under different magnetic field intensities and different magnetic field directions; wherein, the measurement data includes: the actual measured working point and the actual measured release point; Step 4): The MCU unit determines the detection results of each magnetic sensor chip to be tested under different magnetic field intensities and different magnetic field directions according to the preset test parameters and the measurement data.

7. The magnetic sensor chip testing method based on MCU according to claim 6, characterized in that, Before step 1), it further includes: Setting test parameters, the test parameters including: working point, release point, working voltage, magnetic field increase step, magnetic field decrease step, and step angle.

8. The magnetic sensor chip testing method based on MCU according to claim 7, characterized in that, Step 3) further includes: Testing the working current of each magnetic sensor chip to be tested under the preset working voltage.

9. The magnetic sensor chip testing method based on MCU according to claim 7, characterized in that,In step 3), controlling the magnetic field intensity and magnetic field direction when testing the magnetic sensor chips to be tested includes: Changing the magnetic field intensity where the magnetic sensor chips to be tested are located with the preset magnetic field increase step or magnetic field decrease step; Rotating the stepping motor with the preset step angle to change the test angle of the magnetic sensor chips to be tested.

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