Testing system for testing chip and chip testing method

Abstract

The embodiment of the invention discloses a test system for testing a chip and a chip test method, relates to the technical field of integrated circuit test, and aims to reduce the error of a calibration value of a specified register. The system comprises a load board which is used for arranging a chip to be tested; the input end of the amplifying circuit is used for being connected with a specified pin of the chip to be tested; the voltage of the specified pin has a corresponding relationship with a calibration value of a specified register in the chip to be tested; the test machine is respectively connected with the load board and the output end of the amplification circuit, and is used for measuring the voltage output by the output end of the amplification circuit to obtain a first test voltage when the chip to be tested is in a normal working mode, and testing the chip to be tested according to the first test voltage; and determining whether to adjust the calibration value of the specified register. The method is suitable for adjusting the calibration value of the specified register.

Description

Technical Field

[0001] This application relates to the field of integrated circuit testing technology, and particularly to a test system for testing a chip and a chip testing method. Background Art

[0002] During the operation of a chip, its temperature needs to be monitored. The realization of this monitoring function is related to the value of a specified register in the chip, that is, the accuracy of the value of the specified register affects the accuracy of temperature monitoring, and the value of the specified register is related to the voltage value on a specified pin of the chip.

[0003] In the prior art, an automatic test equipment (also known as a test machine (ATE, Automated Test Equipment)) is used to measure the output voltage of a specified pin of a chip to calibrate the calibration value in the specified register. The existing technical method directly uses the ATE. Specifically, the ATE is connected to the specified pin of the chip through a load board for measurement. The accuracy of the measurement result completely depends on the measurement accuracy of the ATE, and the ATE cannot meet the accuracy requirements of the chip for voltage, resulting in a large error in the calibration value of the specified register, further affecting the accuracy of temperature monitoring. Summary of the Invention

[0004] In view of this, embodiments of the present application provide a test system for testing a chip and a chip testing method, which can reduce the error of the calibration value of the specified register.

[0005] In a first aspect, an embodiment of the present application provides a test system for testing a chip, including: a load board for setting a chip to be tested; an amplifying circuit, an input end of the amplifying circuit is used to be connected to a specified pin of the chip to be tested; there is a corresponding relationship between the voltage of the specified pin and the calibration value of a specified register in the chip to be tested; a test machine, the test machine is respectively connected to the load board and an output end of the amplifying circuit, and is used to measure the voltage output by the output end of the amplifying circuit to obtain a first test voltage when the chip to be tested is in a normal working mode, and determine whether to adjust the calibration value of the specified register according to the first test voltage.

[0006] According to a specific implementation manner of an embodiment of the present application, the test machine includes: a measurement module and a determination module; wherein, the measurement module is used to measure the voltage output by the output end of the amplifying circuit to obtain a first test voltage; the determination module is used to determine whether to adjust the calibration value of the specified register according to the first test voltage, the amplification factor of the amplifying circuit, and the expected voltage of the specified pin.

[0007] According to a specific implementation manner of an embodiment of the present application, the determining module includes: an arithmetic sub-module and an adjustment sub-module; wherein, the arithmetic sub-module is configured to divide the first test voltage by the amplification factor of the amplification circuit to obtain a converted first test voltage; calculate a difference between the converted first test voltage and the expected voltage of the specified pin, and use this difference as a voltage deviation value; the adjustment sub-module is configured to, if the voltage deviation value is less than or equal to a preset threshold, use the calibration value of the specified register as the target calibration value and end the test; if the voltage deviation value is greater than the preset threshold, adjust the calibration value of the specified register.

[0008] According to a specific implementation manner of an embodiment of the present application, the adjustment sub-module is specifically configured to: if the voltage deviation value is greater than the preset threshold, configure a new calibration value for the specified register; measure the voltage output at the output end of the amplification circuit to obtain a new first test voltage, and determine whether to adjust the new calibration value according to the new first test voltage, the amplification factor of the amplification circuit, and the expected voltage of the specified pin.

[0009] According to a specific implementation manner of an embodiment of the present application, the adjustment sub-module is specifically configured to: determine an adjustment step size of the calibration value of the specified register according to the voltage deviation value and the voltage accuracy value of the specified pin; configure a new calibration value for the specified register according to the adjustment step size.

[0010] According to a specific implementation manner of an embodiment of the present application, the adjustment sub-module is specifically configured to: divide the new first test voltage by the amplification factor of the amplification circuit to obtain a converted new first test voltage; calculate a difference between the converted new first test voltage and the expected voltage of the specified pin, and use this difference as a new voltage deviation value; if the new voltage deviation value is less than or equal to the preset threshold, use the new calibration value of the specified register as the target calibration value and end the test; if the new voltage deviation value is greater than the preset threshold, adjust the new calibration value of the specified register.

[0011] According to a specific implementation manner of an embodiment of the present application, the adjustment sub-module is specifically configured to: if the new voltage deviation value is greater than the preset threshold, respectively configure a first calibration value and a second calibration value for the specified register, where the first calibration value is the new calibration value of the specified register plus the minimum granularity of the calibration value stored in the specified register, and the second calibration value is the new calibration value of the specified register minus the minimum granularity of the calibration value stored in the specified register; for the first calibration value, measure the voltage output at the output end of the amplifier circuit to obtain a second test voltage, and divide the second test voltage by the amplification factor of the amplifier circuit to obtain a converted second test voltage; for the second calibration value, measure the voltage output at the output end of the amplifier circuit to obtain a third test voltage, and divide the third test voltage by the amplification factor of the amplifier circuit to obtain a converted third test voltage; respectively determine whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the specified pin; where the minimum value of the required voltage range is the difference between the expected voltage of the specified pin and the voltage accuracy of the specified pin, and the maximum value is the sum of the expected voltage of the specified pin and the voltage accuracy of the specified pin; use the calibration value of the specified register corresponding to the test voltage that is within the required voltage range of the specified pin and is closer to the expected voltage of the specified pin among the converted second test voltage, the converted third test voltage, and the converted new first test voltage as the target calibration value of the specified register; if the converted second test voltage, the converted third test voltage, and the converted new first test voltage are not within the required voltage range of the specified pin, the test ends.

[0012] According to a specific implementation manner of an embodiment of the present application, it further includes: a voltage source; a first switch, the first end of the first switch is connected to the voltage source, and the second end is connected to the input end of the amplifier circuit; the voltage source is used to provide a preset voltage value to the amplifier circuit; a second switch, the first end of the second switch is connected to the specified pin, and the second end is connected to the input end of the amplifier circuit; the testing machine is further configured to measure the voltage output at the output end of the amplifier circuit to obtain a fourth test voltage in a state where the first switch is turned on, and determine the amplification factor of the amplifier circuit according to the fourth test voltage and the preset voltage value; the testing machine is specifically configured to measure the first test voltage output at the output end of the amplifier circuit in a state where the second switch is turned on and the chip under test is in the normal operating mode, and determine whether to adjust the calibration value of the specified register according to the first test voltage value.

[0013] According to a specific implementation manner of an embodiment of the present application, it further includes: the amplifying circuit and / or the voltage source are arranged in the load board.

[0014] In a second aspect, an embodiment of the present application provides a chip testing method, which is applied to a testing machine and includes: when the chip to be tested is in a normal working mode, measuring the voltage output at the output end of the amplifying circuit to obtain a first test voltage; wherein, the input end of the amplifying circuit is connected to a specified pin of the chip to be tested; the first test voltage corresponds to the voltage of the specified pin of the chip to be tested, and the voltage of the specified pin has a corresponding relationship with the calibration value of a specified register in the chip to be tested; determining whether to adjust the calibration value of the specified register according to the first test voltage.

[0015] According to a specific implementation manner of an embodiment of the present application, the determining whether to adjust the calibration value of the specified register according to the first test voltage includes: determining whether to adjust the calibration value of the specified register according to the first test voltage, the amplification factor of the amplifying circuit, and the expected voltage of the specified pin.

[0016] According to a specific implementation manner of an embodiment of the present application, the determining whether to adjust the calibration value of the specified register according to the first test voltage, the amplification factor of the amplifying circuit, and the expected voltage of the specified pin includes: dividing the first test voltage by the amplification factor of the amplifying circuit to obtain a converted first test voltage; calculating the difference between the converted first test voltage and the expected voltage of the specified pin, and using this difference as a voltage deviation value; if the voltage deviation value is less than or equal to a preset threshold, taking the calibration value of the specified register as the target calibration value and ending the test; if the voltage deviation value is greater than the preset threshold, adjusting the calibration value of the specified register.

[0017] According to a specific implementation manner of an embodiment of the present application, the adjusting the calibration value of the specified register if the voltage deviation value is greater than the preset threshold includes: if the voltage deviation value is greater than the preset threshold, configuring a new calibration value for the specified register; measuring the voltage output at the output end of the amplifying circuit to obtain a new first test voltage, and determining whether to adjust the new calibration value according to the new first test voltage, the amplification factor of the amplifying circuit, and the expected voltage of the specified pin.

[0018] According to a specific implementation manner of an embodiment of the present application, the configuring a new calibration value for the specified register includes: determining an adjustment step size of the calibration value of the specified register according to the voltage deviation value and the voltage accuracy value of the specified pin; configuring a new calibration value for the specified register according to the adjustment step size.

[0019] According to a specific implementation manner of an embodiment of the present application, determining whether to adjust a new calibration value according to the new first test voltage, the amplification factor of the amplification circuit, and the expected voltage of the specified pin includes: dividing the new first test voltage by the amplification factor of the amplification circuit to obtain a converted new first test voltage; calculating a difference between the converted new first test voltage and the expected voltage of the specified pin, and using this difference as a new voltage deviation value; if the new voltage deviation value is less than or equal to the preset threshold, using the new calibration value of the specified register as the target calibration value, and the test ends; if the new voltage deviation value is greater than the preset threshold, adjusting the new calibration value of the specified register.

[0020] According to a specific implementation manner of an embodiment of the present application, if the new voltage deviation value is greater than the preset threshold, adjusting the new calibration value of the specified register includes: if the new voltage deviation value is greater than the preset threshold, respectively configuring a first calibration value and a second calibration value for the specified register, where the first calibration value is the new calibration value of the specified register plus the minimum granularity of the calibration value stored in the specified register, and the second calibration value is the new calibration value of the specified register minus the minimum granularity of the calibration value stored in the specified register; for the first calibration value, measuring the voltage output at the output end of the amplification circuit to obtain a second test voltage, and dividing the second test voltage by the amplification factor of the amplification circuit to obtain a converted second test voltage; for the second calibration value, measuring the voltage output at the output end of the amplification circuit to obtain a third test voltage, and dividing the third test voltage by the amplification factor of the amplification circuit to obtain a converted third test voltage; respectively determining whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the specified pin; where the minimum value of the required voltage range is the difference between the expected voltage of the specified pin and the voltage accuracy of the specified pin, and the maximum value is the sum of the expected voltage of the specified pin and the voltage accuracy of the specified pin; using the calibration value of the specified register corresponding to the test voltage that is within the required voltage range of the specified pin and closer to the expected voltage of the specified pin among the converted second test voltage, the converted third test voltage, and the converted new first test voltage as the target calibration value of the specified register; if the converted second test voltage, the converted third test voltage, and the converted new first test voltage are not within the required voltage range of the specified pin, the test ends.

[0021] According to a specific implementation manner of an embodiment of the present application, it further includes: when the first switch is in the conducting state, measuring the voltage output at the output end of the amplifying circuit to obtain a fourth test voltage; determining the amplification factor of the amplifying circuit according to the fourth test voltage and the preset voltage value; the first end of the first switch is connected to a voltage source, and the second end is connected to the input end of the amplifying circuit; when the chip under test is in the normal working mode, measuring the voltage output at the output end of the amplifying circuit to obtain a first test voltage, including: when the second switch is in the conducting state and the chip under test is in the normal working mode, measuring the first test voltage output at the output end of the amplifying circuit; the first end of the second switch is connected to the specified pin, and the second end is connected to the input end of the amplifying circuit.

[0022] For the test system and chip test method for testing a chip according to this embodiment, a load board is provided with the chip under test, the input end of the amplifying circuit is connected to the specified pin of the chip under test, and there is a corresponding relationship between the voltage of the specified pin and the calibration value of the specified register in the chip under test. The tester is respectively connected to the load board and the output end of the amplifying circuit. When the chip under test is in the normal working mode, the voltage output at the output end of the amplifying circuit is measured to obtain a first test voltage, and whether to adjust the calibration value of the specified register is determined according to the first test voltage. Since the output end of the amplifying circuit is the voltage after the output voltage of the specified pin of the chip under test is amplified by the amplifying circuit, in this way, the required accuracy of the output voltage of the specified pin of the chip under test after amplification is also amplified, and it is convenient for the measuring accuracy of the tester to meet the accuracy requirements after amplification. On this basis, the tester measures the voltage output at the output end of the amplifying circuit to obtain a first test voltage, and then determines whether to adjust the calibration value of the specified register in the chip under test according to the first test voltage, which can reduce the error of the calibration value of the specified register. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is a schematic structural diagram of a test system for testing a chip provided by an embodiment of the present application; Figure 2 It is a schematic flowchart of a chip test method provided by an embodiment of the present application; Figure 3 It is a schematic flowchart of a chip test method provided by a specific embodiment of the present application. Detailed implementation manners

[0025] The embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0026] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more, unless otherwise specifically defined.

[0027] To enable those skilled in the art to better understand the technical concept, implementation scheme and beneficial effects of the embodiments of the present application, the following will be described in detail through specific embodiments.

[0028] Figure 1 The structural schematic diagram of the test system for testing a chip provided by an embodiment of the present application is as Figure 1 shown. The test system for testing a chip in this embodiment may include: a load board (not shown in the figure), an amplification circuit 1, and a tester 2; wherein, the load board is used to set the chip under test 3; the input end of the amplification circuit 1 is used to be connected to the designated pin of the chip under test 3; there is a corresponding relationship between the voltage of the designated pin and the calibration value of the designated register in the chip under test 3; the tester 2 is respectively connected to the load board and the output end of the amplification circuit 1, and is used to measure the voltage output by the output end of the amplification circuit 1 when the chip under test 3 is in the normal working mode, obtain the first test voltage, and determine whether to adjust the calibration value of the designated register according to the first test voltage.

[0029] Traces (or wirings) can be arranged in the load board, and signals can be transmitted between multiple devices or components connected to the load board through the traces.

[0030] In this embodiment, during use, the chip under test 3 is set on the load board and connected to the tester 2 through the traces in the load board. In this way, the tester 2 can send signals to the chip under test 3 through the traces in the load board to make the chip under test 3 in the normal working mode.

[0031] The amplification circuit 1 is a circuit with a certain amplification factor. During use, the input end of the amplification circuit 1 is connected to the designated pin of the chip under test 3. In this way, through the amplification circuit 1, the voltage of the designated pin of the chip under test 3 can be amplified and output through the output end of the amplification circuit 1.

[0032] If the voltage requirement for a specified pin is 600 ± 0.6 mv, and the measurement accuracy of the ATE is ±2 mv, the ATE using the existing technology cannot meet the voltage requirement for the specified pin. However, in this embodiment, if the amplification factor of the amplifier circuit 1 is 5, after the voltage of the specified pin is amplified by the amplifier circuit 1, the voltage requirement changes to 3000 ± 3 mv, so that the ATE can meet the measurement accuracy requirements of the chip.

[0033] In an example, the amplification factor of the amplifier circuit 1 can be determined according to the measurement accuracy of the ATE and the voltage accuracy of the specified pin of the chip under test 3. Specifically, the amplification factor of the amplifier circuit 1 is greater than or equal to the value obtained by dividing the measurement accuracy of the ATE by the voltage accuracy of the specified pin of the chip under test 3.

[0034] There is a corresponding relationship between the voltage of the specified pin in this embodiment and the calibration value of the specified register in the chip under test 3.

[0035] The tester 2 is connected to the output end of the amplifier circuit 1. In this way, the tester 2 can measure the voltage output from the output end of the amplifier circuit 1 to obtain the first test voltage. The voltage output from the output end of the amplifier circuit 1 is the voltage of the specified pin of the chip under test 3 after being amplified by the amplifier circuit 1. Then, based on the first test voltage, the tester 2 can determine whether to adjust the calibration value of the specified register.

[0036] During use, the tester 2 can send signals such as power supply and clock to the chip under test 3 through the traces in the load board to make the chip under test 3 in the normal working mode. When the chip under test 3 is in the normal working mode, the tester 2 measures the voltage output from the output end of the amplifier circuit 1 to obtain the first test voltage. There is a corresponding relationship between the voltage of the specified pin and the calibration value of the specified register in the chip under test 3. In this way, the tester 2 can determine whether to adjust the calibration value of the specified register based on the first test voltage.

[0037] In this embodiment, a load board is provided with a chip 3 to be tested. The input end of the amplifier circuit 1 is connected to a specified pin of the chip 3 to be tested. There is a corresponding relationship between the voltage of the specified pin and the calibration value of the specified register in the chip 3 to be tested. The tester 2 is respectively connected to the load board and the output end of the amplifier circuit 1. When the chip 3 to be tested is in the normal working mode, the voltage output from the output end of the amplifier circuit 1 is measured to obtain a first test voltage, and based on the first test voltage, it is determined whether to adjust the calibration value of the specified register. Since the output end of the amplifier circuit 1 is the voltage obtained by amplifying the output voltage of the specified pin of the chip 3 to be tested by the amplifier circuit 1, in this way, the required precision of the output voltage of the specified pin of the chip 3 to be tested after amplification is also amplified. It is convenient for the measurement precision of the tester 2 to meet the amplified precision requirements. On this basis, the tester 2 measures the voltage output from the output end of the amplifier circuit 1 to obtain the first test voltage, and then based on the first test voltage, it is determined whether to adjust the calibration value of the specified register in the chip 3 to be tested, which can reduce the error of the calibration value of the specified register. Further, it can improve the accuracy of temperature monitoring of the chip 3 to be tested.

[0038] There are many implementation manners for the tester 2 to determine whether to adjust the calibration value of the specified register according to the first test voltage. As a relatively direct and convenient manner, in some examples, the tester 2 may include: a measurement module and a determination module; wherein, the measurement module is used to measure the first test voltage output from the output end of the amplifier circuit 1; the determination module is used to determine whether to adjust the calibration value of the specified register according to the first test voltage, the amplification factor of the amplifier circuit 1, and the expected voltage of the specified pin.

[0039] If the voltage requirement of the specified pin is 600 ± 0.6 mv, then 600 mv is the expected voltage of the specified pin.

[0040] As a relatively specific example, the determination module includes: an arithmetic sub-module and an adjustment sub-module.

[0041] The arithmetic sub-module is used to divide the first test voltage by the amplification factor of the amplifier circuit 1 to obtain the converted first test voltage; calculate the difference between the converted first test voltage and the expected voltage of the specified pin, and take this difference as the voltage deviation value; the adjustment sub-module is used to, if the voltage deviation value is less than or equal to the preset threshold, take the calibration value of the specified register as the target calibration value and end the test; if the voltage deviation value is greater than the preset threshold, adjust the calibration value of the specified register.

[0042] The preset threshold can be determined according to the performance and rated parameters of the chip 3 to be tested.

[0043] If the voltage deviation value is less than or equal to the preset threshold, it indicates that the current voltage of the specified pin is within the required range. Correspondingly, the current calibration value of the specified register is also relatively accurate.

[0044] If the voltage deviation value is greater than the preset threshold, it indicates that the current voltage value of the specified pin is not within the required range, and the current calibration value of the specified register is also inaccurate, and it needs to be adjusted.

[0045] In the case where the voltage deviation value is greater than the preset threshold, when adjusting the calibration value of the specified register, it is possible to combine the current calibration value of the specified register and existing experience to assign a calibration value to the specified register and use this calibration value as the target calibration value. However, the error of the calibration value determined in this way is still relatively large. To reduce the error of the calibration value of the specified register, in some examples, the adjustment sub-module is specifically used for: if the voltage deviation value is greater than the preset threshold, configuring a new calibration value for the specified register; measuring the voltage output at the output end of amplifier circuit 1 to obtain a new first test voltage, and determining whether to adjust the new calibration value according to the new first test voltage, the amplification factor of amplifier circuit 1, and the expected voltage of the specified pin.

[0046] When configuring a new calibration value for the specified register, a preset value can be added to the original calibration value. However, using this method to obtain the new calibration value has a low efficiency in determining the target calibration value of the specified register. To improve the determination efficiency of the target calibration value of the register, in some examples, the adjustment sub-module is specifically used for: determining the adjustment step of the calibration value of the specified register according to the voltage deviation value and the voltage accuracy value of the specified pin; configuring a new calibration value for the specified register according to the adjustment step.

[0047] In this embodiment, the adjustment step is determined by combining the voltage deviation value and the voltage accuracy value of the specified pin. Further, a new calibration value is configured for the specified register according to the adjustment step. In a specific example, the adjustment step is added to the original calibration value of the specified register to obtain the new calibration value.

[0048] In the case of configuring a new calibration value for the specified register, the adjustment sub-module of tester 2 can specifically be used for dividing the new first test voltage by the amplification factor of amplifier circuit 1 to obtain the converted new first test voltage; calculating the difference between the converted new first test voltage and the expected voltage of the specified pin, and using this difference as the new voltage deviation value; if the new voltage deviation value is less than or equal to the preset threshold, using the new calibration value of the specified register as the target calibration value and ending the test; if the new voltage deviation value is greater than the preset threshold, adjusting the new calibration value of the specified register.

[0049] In this embodiment, the process of determining the new voltage deviation value is similar to the process of determining the voltage deviation value in the foregoing embodiment.

[0050] If the new voltage deviation value is less than or equal to the preset threshold, it means that the accuracy of the new calibration value of the specified register meets the requirements, and the new calibration value can be used as the target calibration value, and the test ends; if the new voltage deviation value is greater than the preset threshold, it means that the new calibration value of the specified register needs to be further adjusted.

[0051] In the case where the new voltage deviation value is greater than the preset threshold, the calibration value of the specified register needs to be further adjusted. To improve the determination efficiency of the calibration value, in some embodiments, the adjustment sub-module is specifically configured to: If the new voltage deviation value is greater than the preset threshold, the first calibration value and the second calibration value are respectively configured for the specified register. The first calibration value is the new calibration value of the specified register plus the minimum granularity of the calibration value stored in the specified register, and the second calibration value is the new calibration value of the specified register minus the minimum granularity of the calibration value stored in the specified register; For the first calibration value, measure the voltage output at the output end of the amplifier circuit 1 to obtain the second test voltage, and divide the second test voltage by the amplification factor of the amplifier circuit 1 to obtain the converted second test voltage; For the second calibration value, measure the voltage output at the output end of the amplifier circuit 1 to obtain the third test voltage, and divide the third test voltage by the amplification factor of the amplifier circuit 1 to obtain the converted third test voltage; Respectively determine whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the specified pin; wherein, the minimum value of the required voltage range is the difference between the expected voltage of the specified pin and the voltage accuracy of the specified pin, and the maximum value is the sum of the expected voltage of the specified pin and the voltage accuracy of the specified pin; Among the converted second test voltage, the converted third test voltage, and the converted new first test voltage, use the calibration value of the specified register corresponding to the test voltage that is within the required voltage range of the specified pin and is closer to the expected voltage of the specified pin as the target calibration value of the specified register; If the converted second test voltage, the converted third test voltage, and the converted new first test voltage are not within the required voltage range of the specified pin, the test ends.

[0052] In a specific example, the specified register stores any integer from 0 to 255, then the minimum granularity of the calibration value stored in the specified register is 1. Further, the first calibration value is the new calibration value of the specified register plus 1, and the second calibration value is the new calibration value of the specified register minus 1.

[0053] For the first calibration value and the second calibration value respectively, measure the corresponding second test voltage and third test voltage, and divide the two test voltages by the amplification factor of the amplifier circuit 1, so as to obtain the converted second test voltage and third test voltage. Determine whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the specified pin. If one of the three test voltages is within the required voltage range of the specified pin, determine the calibration value of the specified register corresponding to this test voltage as the target calibration value; if at least two of the three test voltages are within the required voltage range of the specified pin, determine the calibration value of the specified register corresponding to the test voltage that is closer to the expected voltage of the specified pin among the at least two test voltages as the target calibration value.

[0054] If the converted second test voltage, the converted third test voltage, and the converted new first test voltage are not within the required voltage range of the specified pin, then the chip under test 3 is a chip whose performance does not meet the requirements, and there is no need to determine the target calibration value either, and the test ends.

[0055] To more accurately determine the amplification factor of the amplifier circuit 1, in some examples, the test system further includes a voltage source, a first switch, and a second switch; the first end of the first switch is connected to the voltage source, and the second end is connected to the input end of the amplifier circuit 1; the voltage source is used to provide a preset voltage value to the amplifier circuit 1; the first end of the second switch is connected to the specified pin, and the second end is connected to the input end of the amplifier circuit 1; the tester 2 is further used to measure the voltage output by the output end of the amplifier circuit 1 to obtain a fourth test voltage when the first switch is in the on state, and determine the amplification factor of the amplifier circuit 1 according to the fourth test voltage and the preset voltage value; specifically, the tester 2 is used to measure the voltage output by the output end of the amplifier circuit 1 to obtain a first test voltage when the second switch is in the on state and the chip under test 3 is in the normal working mode, and determine whether to adjust the calibration value of the specified register according to the first test voltage value.

[0056] It can be understood that when the first switch is in the on state, the second switch is in the off state; when the first switch is in the off state, the second switch is in the on state.

[0057] The first switch may further include a third end, and the third end is connected to the tester 2. The tester 2 can send a control signal to the third end to turn on the first switch; the second switch may further include a third end, and the third end is connected to the tester 2. The tester 2 can send a control signal to the third end to turn on the second switch.

[0058] In some examples, the amplifier circuit 1 and / or the voltage source may be provided in the load board.

[0059] Figure 2 The flowchart of the chip testing method provided by an embodiment of the present application is shown as Figure 2 As shown, the chip testing method of this embodiment is applied to a tester and may include: S101. When the chip under test is in the normal working mode, measure the voltage output at the output end of the amplifying circuit to obtain the first test voltage.

[0060] In this embodiment, the input end of the amplifying circuit is connected to the specified pin of the chip under test; the first test voltage corresponds to the voltage of the specified pin of the chip under test, and the voltage of the specified pin has a corresponding relationship with the calibration value of the specified register in the chip under test.

[0061] For example, if the voltage requirement of the specified pin of the chip under test is 600±0.6mv, and the measurement accuracy of the ATE is ±2mv, the existing ATE technology cannot meet the voltage requirement of the specified pin. In this embodiment, through the amplifying circuit, if the amplification factor of the amplifying circuit is 5, the voltage requirement becomes 3000±3mv. In this way, the ATE can meet the requirement of the chip measurement accuracy.

[0062] S102. Determine whether to adjust the calibration value of the specified register according to the first test voltage.

[0063] In this embodiment, when the chip under test is in the normal working mode, measure the voltage output at the output end of the amplifying circuit to obtain the first test voltage. The first test voltage corresponds to the voltage of the specified pin of the chip under test, and the voltage of the specified pin has a corresponding relationship with the calibration value of the specified register in the chip under test. Since the amplifying circuit amplifies the voltage of the specified pin of the chip under test, in this way, it is convenient for the measurement accuracy of the tester to meet the amplified accuracy requirement. On this basis, the tester measures the voltage output at the output end of the amplifying circuit to obtain the first test voltage, and then determines whether to adjust the calibration value of the specified register in the chip under test according to the first test voltage, which can reduce the error of the calibration value of the specified register. Further, it can improve the accuracy of the temperature monitoring of the chip under test.

[0064] There are many implementation manners for determining whether to adjust the calibration value of the specified register according to the first test voltage. As a relatively direct and convenient manner, in some examples, determining whether to adjust the calibration value of the specified register according to the first test voltage in step S102 above may include: S102a. Determine whether to adjust the calibration value of the specified register according to the first test voltage, the amplification factor of the amplifying circuit, and the expected voltage of the specified pin.

[0065] If the voltage requirement for a specified pin is 600 ± 0.6 mv, then 600 mv is the expected voltage of the specified pin.

[0066] As a more specific example, determining whether to adjust the calibration value of a specified register according to the first test voltage, the amplification factor of the amplifier circuit, and the expected voltage of the specified pin in step S102a includes: A1. Divide the first test voltage by the amplification factor of the amplifier circuit to obtain the converted first test voltage; calculate the difference between the converted first test voltage and the expected voltage of the specified pin, and use this difference as the voltage deviation value.

[0067] A2. If the voltage deviation value is less than or equal to a preset threshold, then use the calibration value of the specified register as the target calibration value, and the test ends.

[0068] The preset threshold can be determined according to the performance and rated parameters of the chip to be tested.

[0069] If the voltage deviation value is less than or equal to the preset threshold, it means that the current voltage of the specified pin is within the required range. Correspondingly, the current calibration value of the specified register is also relatively accurate.

[0070] A3. If the voltage deviation value is greater than the preset threshold, then adjust the calibration value of the specified register.

[0071] If the voltage deviation value is greater than the preset threshold, it means that the current voltage value of the specified pin is not within the required range, and the current calibration value of the specified register is also inaccurate, and it needs to be adjusted.

[0072] In the case where the voltage deviation value is greater than the preset threshold, when adjusting the calibration value of the specified register, a calibration value can be assigned to the specified register in combination with the current calibration value of the specified register and existing experience, and this calibration value is used as the target calibration value. However, the error of the calibration value determined in this way is still relatively large. To reduce the error of the calibration value of the specified register, in some examples, if the voltage deviation value is greater than the preset threshold in step A3, then adjusting the calibration value of the specified register may include: A30. If the voltage deviation value is greater than the preset threshold, configure a new calibration value for the specified register.

[0073] A31. Measure the voltage output at the output end of the amplifier circuit to obtain a new first test voltage.

[0074] A32. Determine whether to adjust the new calibration value according to the new first test voltage, the amplification factor of the amplifier circuit, and the expected voltage of the specified pin.

[0075] When configuring a new calibration value for a specified register, a preset value can be added to the original calibration value. However, using this method to obtain the new calibration value is less efficient in determining the target calibration value of the specified register. To improve the efficiency of determining the target calibration value of the register, in some examples, configuring a new calibration value for the specified register in step A30 may include: A30a. Determine the adjustment step size of the calibration value of the specified register according to the voltage deviation value and the voltage accuracy value of the specified pin.

[0076] A30b. Configure a new calibration value for the specified register according to the adjustment step size.

[0077] Based on the original calibration value of the specified register, adding the adjustment step size can obtain the new calibration value.

[0078] When configuring a new calibration value for the specified register, determining whether to adjust the new calibration value according to the new first test voltage, the amplification factor of the amplifier circuit, and the expected voltage of the specified pin in step A32 may include: A32a. Divide the new first test voltage by the amplification factor of the amplifier circuit to obtain the converted new first test voltage.

[0079] Based on the configured new calibration value, measure the new first test voltage output from the output end of the amplifier circuit. After obtaining the new first test voltage, combine the amplification factor of the amplifier circuit to obtain the converted new first test voltage.

[0080] A32b. Calculate the difference between the converted new first test voltage and the expected voltage of the specified pin, and use this difference as the new voltage deviation value.

[0081] A32c. If the new voltage deviation value is less than or equal to the preset threshold, use the new calibration value of the specified register as the target calibration value and end the test.

[0082] If the new voltage deviation value is less than or equal to the preset threshold, it means that the accuracy of the new calibration value of the specified register meets the requirements, and the new calibration value can be used as the target calibration value and the test ends.

[0083] A32d. If the new voltage deviation value is greater than the preset threshold, adjust the new calibration value of the specified register.

[0084] If the new voltage deviation value is greater than the preset threshold, it means that the new calibration value of the specified register needs further adjustment.

[0085] In the case where the new voltage deviation value is greater than the preset threshold, it is necessary to further adjust the calibration value of the specified register. To improve the determination efficiency of the calibration value, in some embodiments, if the new voltage deviation value is greater than the preset threshold in step A32d, adjusting the new calibration value of the specified register may include: A32da. If the new voltage deviation value is greater than the preset threshold, respectively configure a first calibration value and a second calibration value for the specified register again.

[0086] The first calibration value is the new calibration value of the specified register plus the minimum granularity of the calibration value stored in the specified register, and the second calibration value is the new calibration value of the specified register minus the minimum granularity of the calibration value stored in the specified register.

[0087] In a specific example, if the specified register stores any integer from 0 to 255, then the minimum granularity of the calibration value stored in the specified register is 1. Further, the first calibration value is the new calibration value of the specified register plus 1, and the second calibration value is the new calibration value of the specified register minus 1.

[0088] A32db. For the first calibration value, measure the voltage output at the output end of the amplifier circuit to obtain a second test voltage, and divide the second test voltage by the amplification factor of the amplifier circuit to obtain a converted second test voltage.

[0089] A32dc. For the second calibration value, measure the voltage output at the output end of the amplifier circuit to obtain a third test voltage, and divide the third test voltage by the amplification factor of the amplifier circuit to obtain a converted third test voltage.

[0090] A32dd. Respectively determine whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the specified pin.

[0091] Among them, the minimum value of the required voltage range is the difference between the expected voltage of the specified pin and the voltage accuracy of the specified pin, and the maximum value is the sum of the expected voltage of the specified pin and the voltage accuracy of the specified pin.

[0092] A32de. Use the calibration value of the specified register corresponding to the test voltage that is within the required voltage range of the specified pin and is closer to the expected voltage of the specified pin among the converted second test voltage, the converted third test voltage, and the converted new first test voltage as the target calibration value of the specified register.

[0093] If one of the three test voltages is within the required voltage range of the specified pin, the calibration value of the specified register corresponding to this test voltage is determined as the target calibration value; if at least two of the three test voltages are within the required voltage range of the specified pin, the calibration value of the specified register corresponding to the test voltage that is closer to the expected voltage of the specified pin among these at least two test voltages is determined as the target calibration value.

[0094] A32df. If the converted second test voltage, the converted third test voltage, and the converted new first test voltage are all not within the required voltage range of the specified pin, the test ends.

[0095] If the converted second test voltage, the converted third test voltage, and the converted new first test voltage are all not within the required voltage range of the specified pin, then the chip under test is a chip whose performance does not meet the requirements, and there is no need to determine the target calibration value either, and the test ends.

[0096] To more accurately determine the amplification factor of the amplifier circuit, in some examples, the method may further include: S103. Measure the voltage output by the output end of the amplifier circuit while the first switch is in the conducting state, and obtain the fourth test voltage.

[0097] The first end of the first switch is connected to a voltage source, and the second end is connected to the input end of the amplifier circuit.

[0098] The first switch may further include a third end, and the third end is connected to the tester vector. The tester can send a control signal to the third end to make the first switch conduct.

[0099] S104. Determine the amplification factor of the amplifier circuit according to the fourth test voltage and the preset voltage value.

[0100] Among them, when the chip under test in step S102 is in the normal working mode and measures the voltage output by the output end of the amplifier circuit to obtain the first test voltage, it includes: S102a. Measure the first test voltage output by the output end of the amplifier circuit while the second switch is in the conducting state and the chip under test is in the normal working mode.

[0101] The first end of the second switch is connected to the specified pin, and the second end is connected to the input end of the amplifier circuit.

[0102] The second switch may further include a third end, and the third end is connected to the tester vector. The tester can send a control signal to the third end to make the second switch conduct.

[0103] It is understandable that when the first switch is in the conducting state, the second switch is in the off state; when the first switch is in the off state, the second switch is in the conducting state.

[0104] The following uses a specific embodiment to elaborate in detail on the solution of this application.

[0105] Refer to Figure 3 , the test system for the chip to be tested in this embodiment: For the code calibration of the TMON BGADJ (temperature monitoring module) register of the chip to be tested, the voltage requirement for pin X is 600 ± 0.6 mV. The measurement accuracy of the tester is ±2 mV. If the tester is directly used for measurement, the measurement accuracy of the ATE cannot reach the accuracy of the chip, which will lead to inaccurate BGADJ code and thus affect the accuracy of the TMON temperature. To solve such a problem, in this embodiment, an amplification circuit and a voltage source are developed on the Loadboard. The amplification factor of the amplification circuit is calculated by the voltage source and is required to be between 4.9 and 5.1. The ATE is connected to the chip through this amplification circuit and tests in a 5-fold amplification circuit. That is, the accuracy requirement of the chip is changed to 3000 ± 3 mV, and indirectly the accuracy of the ATE is improved to 5 times the original, which is ±0.4 mV. In this way, the ATE can meet the requirements of the chip measurement accuracy. Finally, the data is restored to the test range of 600 ± 0.6 mV required by the chip by calculating the actual amplification factor.

[0106] Set the calibration granularity: Vgra = 0.6 mV, and the calibration granularity is determined according to the calibration accuracy.

[0107] The chip test method of this embodiment may include: (1) Configure the default register value.

[0108] Set the initial value (initial calibration value) of the Reg 8bits register in the test vector to 0x80.

[0109] (2) Measure the voltage of the pin.

[0110] Use the ATE to measure the voltage of pin X and record it as Vref.

[0111] (3) Calculate Voff = Vref / M – 600 mV.

[0112] Divide the current test voltage Vref by the amplification factor M to obtain the converted test voltage. Calculate the difference between the converted test voltage and the target voltage (desired voltage), and use this difference as the voltage deviation value Voff. Calculate the deviation value through the above formula.

[0113] (4) Determine whether Voff is less than or equal to the threshold voltage limit (6 mV).

[0114] (5) If Voff ≤ Limit, the calibration ends.

[0115] If Voff ≤ Limit, then the register = 0x80, the default value is the target value, and the calibration ends.

[0116] (6) If Voff > Limit, then calculate the adjustment step size.

[0117] Calculate the adjustment step size step of the Reg register code: step = Voff / Vgra.

[0118] (7) Set the new register value The new register value is tentative_1 = 0x80 + step.

[0119] (8) Measure the pin voltage Re-measure the voltage value of pin X as the new Vref.

[0120] (9) Re-determine whether Voff is less than or equal to limit.

[0121] The deviation value between the current Vref and the target voltage: Voff = Vref / M – 600 mV.

[0122] (10) If Voff ≤ Limit, then the current value of the register tentative_1 is the target value, and the calibration ends.

[0123] (11) If Voff > Limit, adjust one granularity in the direction of the target value. Specifically, the new calibration value of the register tentative_2 = tentative_1 + 1, and tentative_2 = tentative_1 - 1, and re-measure the voltage of pin X.

[0124] (12) Compare the Vref voltages of tentative_1 and tentative_2 respectively, select the voltage that meets the voltage requirement of pin X, and the value of the register corresponding to the Vref closer to the target voltage 600 mV is used as the target value of the register, and the calibration ends.

[0125] The measured voltage corresponding to tentative_1 is Vref1, the measured voltage corresponding to tentative_2 = tentative_1 + 1 is Vref2, and the measured voltage corresponding to tentative_2 = tentative_1 - 1 is Vref3. Compare Vref1, Vref2, and Vref3, and select the voltage among Vref1, Vref2, and Vref3 that meets the voltage requirement of pin X and is closer to the target voltage of 600 mV as the target voltage of pin X. If Vref1 meets the voltage requirement of pin X and is closer to the target voltage of 600 mV, then use the value of the register corresponding to Vref1 as the target value of the register.

[0126] (13) If the calibration Limit still cannot be achieved after completing the above steps, the calibration fails.

[0127] The method of this embodiment is simple, low-cost, and easy to implement.

[0128] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the element.

[0129] Each embodiment in this specification is described in a related manner. For the same or similar parts between the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments.

[0130] For the convenience of description, the above device is described by dividing it into various units / modules according to functions. Of course, when implementing this application, the functions of each unit / module can be implemented in the same or multiple software and / or hardware.

[0131] As described above, the above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in this application should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A test system for testing a chip, characterized in that: include: A load board, the load board is used to set the chip to be tested; an amplifier circuit, wherein an input end of the amplifier circuit is used to be connected to a designated pin of the chip to be tested; a voltage of the designated pin has a corresponding relationship with a calibration value of a designated register in the chip to be tested; A testing machine, the testing machine is respectively connected to the load board and the output end of the amplifier circuit, and is used to measure the voltage output by the output end of the amplifier circuit when the chip to be tested is in a normal working mode, to obtain a first test voltage, and based on the first test voltage, determine whether to adjust the calibration value of the specified register.

2. The test system according to claim 1, characterized in that: The test machine includes: a measuring module and a determining module; wherein, The measuring module is used to measure the voltage outputted by the output terminal of the amplifying circuit to obtain a first test voltage; The determination module is used to determine whether to adjust the calibration value of the designated register according to the first test voltage, the amplification factor of the amplifier circuit and the expected voltage of the designated pin.

3. The test system according to claim 2, characterized in that: The determination module includes: an operation submodule and an adjustment submodule; wherein, The operation submodule is used to divide the first test voltage by the amplification factor of the amplifier circuit to obtain a converted first test voltage; calculate the difference between the converted first test voltage and the expected voltage of the specified pin, and use the difference as a voltage deviation value; The adjustment submodule is used to use the calibration value of the designated register as the target calibration value and end the test if the voltage deviation value is less than or equal to the preset threshold; if the voltage deviation value is greater than the preset threshold, adjust the calibration value of the designated register.

4. The test system according to claim 3, characterized in that: The adjustment submodule is specifically used for: If the voltage deviation value is greater than the preset threshold, a new calibration value is configured for the designated register; the voltage outputted from the output end of the amplifier circuit is measured to obtain a new first test voltage, and based on the new first test voltage, the amplification factor of the amplifier circuit and the expected voltage of the designated pin, it is determined whether to adjust the new calibration value.

5. The test system according to claim 4, characterized in that: The adjustment submodule is specifically used for: An adjustment step length of a calibration value of the designated register is determined according to the voltage deviation value and the voltage accuracy value of the designated pin; and a new calibration value is configured for the designated register according to the adjustment step length.

6. The test system according to claim 5, characterized in that: The adjustment submodule is specifically used for: The new first test voltage is divided by the amplification factor of the amplifier circuit to obtain a converted new first test voltage; the difference between the converted new first test voltage and the expected voltage of the specified pin is calculated, and the difference is used as a new voltage deviation value; if the new voltage deviation value is less than or equal to the preset threshold value, the new calibration value of the specified register is used as the target calibration value, and the test ends; If the new voltage deviation value is greater than the preset threshold, the new calibration value of the designated register is adjusted.

7. The test system according to claim 6, characterized in that: The adjustment submodule is specifically used for: If the new voltage deviation value is greater than the preset threshold, a first calibration value and a second calibration value are configured for the designated register respectively, wherein the first calibration value is the new calibration value of the designated register plus the minimum granularity of the calibration value stored in the designated register, and the second calibration value is the new calibration value of the designated register minus the minimum granularity of the calibration value stored in the designated register; With respect to the first calibration value, measuring the voltage outputted by the output terminal of the amplifier circuit to obtain a second test voltage, and dividing the second test voltage by the amplification factor of the amplifier circuit to obtain a converted second test voltage; With respect to the second calibration value, measuring the voltage outputted by the output terminal of the amplifier circuit to obtain a third test voltage, and dividing the third test voltage by the amplification factor of the amplifier circuit to obtain a converted third test voltage; Determine whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the designated pin; wherein the minimum value of the required voltage range is the difference between the expected voltage of the designated pin and the voltage accuracy of the designated pin, and the maximum value is the sum of the expected voltage of the designated pin and the voltage accuracy of the designated pin; The calibration value of the designated register corresponding to the test voltage that is within the required voltage range of the designated pin and closer to the expected voltage of the designated pin among the converted second test voltage, the converted third test voltage and the converted new first test voltage is used as the target calibration value of the designated register; If the converted second test voltage, the converted third test voltage, and the converted new first test voltage are not within the required voltage range of the designated pin, the test ends.

8. The test system according to claim 1, characterized in that: Also includes: Voltage source; a first switch, wherein a first end of the first switch is connected to the voltage source, and a second end of the first switch is connected to an input end of the amplifier circuit; the voltage source is used to provide a preset voltage value to the amplifier circuit; a second switch, wherein a first end of the second switch is connected to the designated pin, and a second end of the second switch is connected to an input end of the amplifier circuit; The test machine is further used to measure the voltage outputted by the output terminal of the amplifier circuit when the first switch is in the on state, and obtain a fourth test voltage, and determine the amplification factor of the amplifier circuit according to the fourth test voltage and the preset voltage value; The tester is specifically used to measure the first test voltage outputted from the output end of the amplifier circuit when the second switch is in the on state and the chip to be tested is in the normal working mode, and determine whether to adjust the calibration value of the designated register according to the first test voltage value.

9. The test system according to claim 8, characterized in that: Also includes: The amplifier circuit and / or the voltage source are arranged in the load board.

10. A chip testing method, characterized in that: Applicable to test machines, including: The chip under test is in a normal working mode, measuring the voltage outputted by the output end of the amplifier circuit to obtain a first test voltage; wherein the input end of the amplifier circuit is connected to a designated pin of the chip under test; the first test voltage corresponds to the voltage of the designated pin of the chip under test, and the voltage of the designated pin has a corresponding relationship with a calibration value of a designated register in the chip under test; Determine whether to adjust the calibration value of the designated register according to the first test voltage.

11. The method according to claim 10, characterized in that The determining, according to the first test voltage, whether to adjust the calibration value of the designated register includes: Whether to adjust the calibration value of the designated register is determined according to the first test voltage, the amplification factor of the amplifier circuit, and the expected voltage of the designated pin.

12. The method according to claim 11, characterized in that The determining whether to adjust the calibration value of the designated register according to the first test voltage, the amplification factor of the amplifier circuit and the expected voltage of the designated pin includes: The first test voltage is divided by the amplification factor of the amplifier circuit to obtain a converted first test voltage; a difference between the converted first test voltage and the expected voltage of the designated pin is calculated, and the difference is used as a voltage deviation value; If the voltage deviation value is less than or equal to the preset threshold, the calibration value of the designated register is used as the target calibration value and the test ends; if the voltage deviation value is greater than the preset threshold, the calibration value of the designated register is adjusted.

13. The method according to claim 12, characterized in that If the voltage deviation value is greater than the preset threshold, adjusting the calibration value of the designated register includes: If the voltage deviation value is greater than the preset threshold, a new calibration value is configured for the designated register; the voltage outputted from the output end of the amplifier circuit is measured to obtain a new first test voltage, and based on the new first test voltage, the amplification factor of the amplifier circuit and the expected voltage of the designated pin, it is determined whether to adjust the new calibration value.

14. The method according to claim 13, characterized in that The configuring a new calibration value for the designated register includes: An adjustment step length of a calibration value of the designated register is determined according to the voltage deviation value and the voltage accuracy value of the designated pin; and a new calibration value is configured for the designated register according to the adjustment step length.

15. The method according to claim 14, characterized in that The determining whether to adjust the new calibration value according to the new first test voltage, the amplification factor of the amplifier circuit and the expected voltage of the designated pin includes: The new first test voltage is divided by the amplification factor of the amplifier circuit to obtain the converted new first test voltage; the difference between the converted new first test voltage and the expected voltage of the designated pin is calculated, and the difference is used as the new voltage deviation value; if the new voltage deviation value is less than or equal to the preset threshold value, the new calibration value of the designated register is used as the target calibration value, and the test ends; if the new voltage deviation value is greater than the preset threshold value, the new calibration value of the designated register is adjusted.

16. The method according to claim 15, characterized in that If the new voltage deviation value is greater than the preset threshold, adjusting the new calibration value of the designated register includes: If the new voltage deviation value is greater than the preset threshold, a first calibration value and a second calibration value are configured for the designated register respectively, wherein the first calibration value is the new calibration value of the designated register plus the minimum granularity of the calibration value stored in the designated register, and the second calibration value is the new calibration value of the designated register minus the minimum granularity of the calibration value stored in the designated register; With respect to the first calibration value, measuring the voltage outputted by the output terminal of the amplifier circuit to obtain a second test voltage, and dividing the second test voltage by the amplification factor of the amplifier circuit to obtain a converted second test voltage; With respect to the second calibration value, measuring the voltage outputted by the output terminal of the amplifier circuit to obtain a third test voltage, and dividing the third test voltage by the amplification factor of the amplifier circuit to obtain a converted third test voltage; Determine whether the converted second test voltage, the converted third test voltage, and the converted new first test voltage are within the required voltage range of the designated pin; wherein the minimum value of the required voltage range is the difference between the expected voltage of the designated pin and the voltage accuracy of the designated pin, and the maximum value is the sum of the expected voltage of the designated pin and the voltage accuracy of the designated pin; The calibration value of the designated register corresponding to the test voltage that is within the required voltage range of the designated pin and closer to the expected voltage of the designated pin among the converted second test voltage, the converted third test voltage and the converted new first test voltage is used as the target calibration value of the designated register; If the converted second test voltage, the converted third test voltage, and the converted new first test voltage are not within the required voltage range of the designated pin, the test ends.

17. The method according to claim 10, characterized in that Also includes: When the first switch is in an on state, measuring the voltage outputted by the output terminal of the amplifier circuit to obtain a fourth test voltage; Determine the amplification factor of the amplifier circuit according to the fourth test voltage and the preset voltage value; the first end of the first switch is connected to the voltage source, and the second end is connected to the input end of the amplifier circuit; The chip under test measures the voltage outputted by the output terminal of the amplifier circuit in the normal working mode to obtain a first test voltage, including: When the second switch is in the on state and the chip under test is in the normal working mode, measuring a first test voltage outputted by the output terminal of the amplifier circuit; A first end of the second switch is connected to the designated pin, and a second end of the second switch is connected to an input end of the amplifier circuit.

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