Voltage reference remote calibration method and system of integrated circuit test system

Abstract

The invention belongs to the technical field of integrated circuit test system metering, and particularly discloses a voltage reference remote calibration method and system of an integrated circuit test system. The system comprises a calibration key and a calibration board. The quantum time unit provides a frequency signal; the chip conversion circuit converts the frequency signal generated by the quantum time unit into a standard voltage signal; the universal meter is used for reading a standard voltage signal; the integrated circuit test system is used for measuring the voltage signal provided by the chip conversion circuit, outputting a test voltage signal, and metering the reference of the integrated circuit test system based on the difference value between the test voltage signal and the standard voltage signal. According to the invention, remote calibration of the voltage reference of the integrated circuit test system is realized.

Description

Technical Field

[0001] This application belongs to the field of metrology technology for integrated circuit test systems. More specifically, it relates to a method and system for remotely calibrating the voltage reference of an integrated circuit test system. Background Art

[0002] The performance and quality of integrated circuits are mainly ensured by integrated circuit test systems. Therefore, as a guarantee device for modern equipment, the integrated circuit test system plays a crucial role in its accurate metrology.

[0003] The metrology means of integrated circuit test systems are usually divided into two types. One is based on the internal reference source of the integrated circuit test system and is calibrated by the integrated circuit test system manufacturer. This method calibrates from inside the integrated circuit, and a special calibration robot is used during calibration. This device is bulky, and during the entire calibration process, it is impossible to achieve the unity of the measured values in the field of integrated circuit test systems for calibration equipment, equipment to be calibrated, calibration software, etc. The second method is to perform calibration outside the integrated circuit test system. The calibration principle is to lead the internal resources of the measurement system to the test end face, and then rely on a customized special fixture and transfer equipment to lead the signal to the calibration device as losslessly as possible. This method can ensure that the key index parameters of the integrated circuit test system can be traced and the unity of the measured values can be achieved. However, the calibration device is bulky, and each time a metrology calibration is required, it is necessary to go to the laboratory where the measurement system is located, which greatly increases the transportation cost and labor cost. Therefore, how to perform remote calibration and reduce the volume of the calibration device for integrated circuit test systems is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] Aiming at the defects of the prior art, the purpose of this application is to provide a method and system for remotely calibrating the voltage reference of an integrated circuit test system, aiming to solve the problem that the existing calibration device for an integrated circuit test system cannot perform remote calibration.

[0005] To achieve the above purpose, in the first aspect, this application provides a system for remotely calibrating the voltage reference of an integrated circuit test system, including a calibration key and a calibration board; During the calibration process, the calibration board is connected to the integrated circuit test system; the calibration key is inserted into the calibration board; The calibration key includes a chip conversion circuit and a serial port data reading circuit; the calibration board includes a quantum time unit and a channel interface; The quantum time unit serves as a quantum time excitation for providing a frequency signal; the chip conversion circuit is used to convert the frequency signal generated by the quantum time unit into a standard voltage signal; The serial port data reading circuit is used to provide an interface for connecting a multimeter to the chip conversion circuit; the multimeter is used to read the standard voltage signal; the channel interface is used to connect the calibration board to the integrated circuit test system; the integrated circuit test system is used to measure the voltage signal provided by the chip conversion circuit, output a test voltage signal, and measure its own reference based on the difference between the test voltage signal and the standard voltage signal.

[0006] Further preferably, the quantum time unit includes a rubidium clock or a cesium clock.

[0007] Further preferably, the chip conversion circuit is the chip AD650. When performing heat preservation and anti-magnetic packaging on the chip AD650, the pins of the chip AD650 are set.

[0008] Further preferably, the connection port between the chip AD650 and the calibration board during calibration is the chip pin of the chip AD650 and the chip fixture reserved on the calibration board.

[0009] In a second aspect, the present application provides a method for remotely calibrating the voltage reference of an integrated circuit test system, including the following steps: When a calibration request is sent by the integrated circuit test system to be calibrated, update the relationship between the frequency signal and the standard voltage signal in the calibration key; Transmit the updated calibration key to the integrated circuit test system to be calibrated, insert the calibration key into the calibration board, provide a frequency signal for the calibration key through the calibration board, convert the frequency signal into a voltage signal through the calibration key, and obtain the standard voltage signal output by the calibration key through the multimeter; at the same time, the integrated circuit test system outputs a test voltage signal; Compare the test voltage signal with the standard voltage signal, and measure the own reference of the integrated circuit test system based on the difference between the two.

[0010] Further preferably, the chip conversion circuit in the calibration key is the chip AD650. When performing heat preservation and anti-magnetic packaging on the chip AD650, expose the pins of the chip AD650.

[0011] Further preferably, the way the chip AD650 is inserted into the calibration board is to connect the chip pins of the chip AD650 to the chip fixture on the calibration board.

[0012] Generally speaking, compared with the prior art through the above technical solutions conceived by the present application, the following beneficial effects are achieved: The present application provides a voltage reference remote calibration system for an integrated circuit test system. Among them, a calibration key can convert a frequency signal into a standard voltage signal. The calibration key has the characteristics of being miniaturized and portable. Therefore, when calibrating the voltage reference of the integrated circuit test system, it only needs to transfer the calibration key to the party of the integrated circuit test system to be calibrated, and there is no need to carry large calibration equipment. Remote calibration of the voltage reference can be achieved.

[0013] The present application provides a voltage reference remote calibration method for an integrated circuit test system. Through quantum technology, by utilizing the constant stability characteristics of the quantum time reference and applying it, a time-voltage conversion model is constructed to convert quantum time parameters into voltage parameters, realizing the unification of the quantity value of the internal voltage reference of the integrated circuit test system, which is an important means to ensure the accuracy and reliability of the integrated circuit test results. Brief Description of the Drawings

[0014] Figure 1 It is a schematic diagram of the method for constructing a voltage reference remote calibration model of an integrated circuit test system provided by an embodiment of the present application; Figure 2 It is a flowchart of the voltage reference remote calibration method of an integrated circuit test system provided by an embodiment of the present application; Figure 3 It is a structural diagram of the calibration system provided by an embodiment of the present application; Figure 4 It is a structural diagram of the calibration system provided by an embodiment of the present application. Detailed Embodiments

[0015] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0016] The term "and / or" in this article is a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The symbol " / " in this article represents that the associated object is an "or" relationship, for example, A / B represents A or B.

[0017] The terms "first" and "second" in the description and claims of this article are used to distinguish different objects, rather than to describe a specific order of the objects.

[0018] In the embodiments of the present application, words such as "exemplary" or "for example" are used to represent examples, illustrations, or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0019] In the description of the embodiments of the present application, unless otherwise specified, the meaning of "a plurality" refers to two or more.

[0020] The embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

[0021] A method for remotely calibrating the voltage reference of an integrated circuit test system, which solves the problem of remote metrology of the voltage reference of the integrated circuit test system.

[0022] The voltage reference of the integrated circuit test system is the most important part for the unity of the quantity values of the entire integrated circuit test system. The voltages and currents of all channels inside the system are traced back to the voltage reference. Therefore, the calibration of the voltage reference is very important; The current existing calibration method is to use a source meter to measure the value of the reference voltage at the output signal port and compare it with the theoretical value to complete the calibration. The instruments and equipment and supporting equipment involved in the entire calibration link are: a high-precision digital multimeter, a calibration board, and a connection cable; among them, the high-precision digital multimeter is large in volume and is easily damaged during transportation, and due to the reason of wiring, it requires the calibration personnel to go to the site to complete; In order to achieve remote calibration of the reference voltage of the integrated circuit test system, first, a quantum time-voltage conversion model is constructed; To achieve remote metrology, there must be a stable excitation. Currently, the quantum voltage device is huge in volume and cannot be applied practically. Quantum time devices such as rubidium clocks and cesium clocks are small in volume and have stable technical indicators, which are the best choice for generating stable excitation and are not easily affected by the environment and other external conditions.

[0023] Therefore, the present application uses a rubidium clock as the quantum time excitation, and the conversion circuit uses the frequency-voltage conversion chip AD650 as the core circuit to convert the frequency signal generated by the rubidium clock into a voltage signal; since the chip itself has instability and its technical indicators cannot be evaluated according to the theory, in order to better ensure the accuracy and stability during the frequency-voltage conversion process, it is necessary to first evaluate the performance of the conversion circuit with the chip AD650 as the core, that is, model construction. The construction method is as Figure 1 shown; The excitation of the conversion circuit with the chip AD650 as the core is the standard frequency signal provided by the rubidium clock, and this signal does not change with location and time; The output end of the conversion circuit with chip AD650 as the core is connected to a high-precision digital multimeter to record the value of the standard voltage; like Figure 1 As shown, the whole model can be calibrated to obtain a standard frequency-voltage conversion model; the model uses the quantum time standard rubidium clock as input and the voltage value as output. The actual value of the voltage output is measured by a high-precision digital multimeter to obtain the relationship between the output voltage and the input frequency, thereby determining the parameter model; After getting the model, a remote metrology calibration method is designed based on the model. The equipment involved in the whole calibration process has a calibration key and a calibration board. The peripheral circuit is designed on the calibration board. The calibration key is a core circuit composed of chip AD650. When calibrating, you only need to connect the two together. The connection port is the chip pin of chip AD650 and the chip fixture reserved on the calibration board. The calibration key is a conversion circuit with AD650 as the core and a data processing circuit that reads and saves the serial port data of the digital multimeter with STM32; the calibration board is composed of a rubidium clock and a channel interface; the specific method of remote calibration is: the calibration board is provided to the calibrated measurement system for long-term safekeeping, and when calibration is required, the calibration key is fixed in the laboratory, the model data is updated, and then it is directly sent to the calibrated measurement system, and the key is inserted into the calibration board and connected to a high-precision digital multimeter. Next, the calibrated party operates the test system to test the standard voltage generated by the key model and compares the test result with the model standard voltage, and then uses the test system test function to measure its own benchmark to complete the entire calibration process. The calibration flow chart is shown below Figure 2 As shown; The calibration key is a conversion circuit with chip AD650 as the core, which is used to convert frequency into voltage. After the circuit is designed, the thermal insulation and magnetic field resistance packaging design is carried out to expose the pins of chip AD650 as the connection port between the key and the calibration board, such as Figure 3 As shown; The bottom of the calibration board is consistent with the current mainstream calibration board and contacts the channel of the integrated circuit test system. The frequency source on the calibration board uses a rubidium clock module as a quantum time reference. The structure is as follows: Figure 4 shown.

[0024] The present application provides a voltage reference remote calibration system for an integrated circuit test system, wherein a frequency signal can be converted into a standard voltage signal through a calibration key, and the calibration key has the characteristics of being miniaturized and portable, so when calibrating the voltage reference of the integrated circuit test system, it is only necessary to transfer the calibration key to the calibrated integrated circuit test system, and it is not necessary to carry large calibration equipment. Remote calibration of the voltage reference can be achieved.

[0025] This application aims to apply quantum technology by utilizing the stable characteristics of quantum benchmarks. By constructing a time-voltage conversion model, the quantum time parameters are converted into voltage parameters to achieve the unification of the magnitude of the internal voltage benchmark in the integrated circuit test system, which is an important means to ensure the accuracy and reliability of the integrated circuit test results.

[0026] It should be understood that expressions such as "including" and "may include" that can be used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as "including" and / or "having" can be interpreted as indicating specific characteristics, numbers, operations, constituent elements, components, or combinations thereof, but cannot be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0027] In addition, in this application, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" can include A, can include B, or can include both A and B.

[0028] In the description of the embodiments of this application, it should be noted that unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. Among them, "fixed connection" means that they are connected to each other and the relative positional relationship after connection remains unchanged. "Rotational connection" means that they are connected to each other and can rotate relative to each other after connection. "Sliding connection" means that they are connected to each other and can slide relative to each other after connection. The orientation terms mentioned in the embodiments of this application, such as "top", "bottom", "inside", "outside", "left", "right", etc., are only references to the directions of the drawings. Therefore, the orientation terms used are for better and clearer description and understanding of the embodiments of this application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of this application.

[0029] In addition, in the embodiments of this application, mathematical concepts such as symmetry, equality, parallelism, and perpendicularity are mentioned. These limitations are all in view of the current technological level, rather than absolute strict definitions in the mathematical sense. A small deviation is allowed, and approximate symmetry, approximate equality, approximate parallelism, approximate perpendicularity, etc. are all acceptable. For example, A is parallel to B means that A is parallel to B or approximately parallel to B, and the included angle between A and B can be between 0 degrees and 10 degrees. A is perpendicular to B means that A is perpendicular to B or approximately perpendicular to B, and the included angle between A and B can be between 80 degrees and 100 degrees.

[0030] As described above, it is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the said claims.

Claims

1. A voltage reference remote calibration system for an integrated circuit test system, characterized in that: Includes calibration key and calibration plate; During the calibration process, the calibration board is connected to the integrated circuit test system; the calibration key is inserted into the calibration board; The calibration key includes a chip conversion circuit and a serial port data reading circuit; the calibration board includes a quantum time unit and a channel interface; The quantum time unit is used as a quantum time excitation to provide a frequency signal; the chip conversion circuit is used to convert the frequency signal generated by the quantum time unit into a standard voltage signal; The serial port data reading circuit is used to provide an interface for connecting the chip conversion circuit to the multimeter; the multimeter is used to read the standard voltage signal; the channel interface is used to connect the calibration board to the integrated circuit test system; the integrated circuit test system is used to measure the voltage signal provided by the chip conversion circuit, output the test voltage signal, and measure its own benchmark based on the difference between the test voltage signal and the standard voltage signal.

2. The voltage reference remote calibration system according to claim 1, characterized in that: The chip conversion circuit is a chip AD650. When the chip AD650 is packaged for heat preservation and magnetic field resistance, the pins of the chip AD650 are set.

3. The voltage reference remote calibration system according to claim 2, characterized in that: During calibration, the connection port between the chip AD650 and the calibration board is the chip pin of the chip AD650 and the chip fixture reserved on the calibration board.

4. The voltage reference remote calibration system according to any one of claims 1 to 3, characterized in that: Quantum time units include rubidium clocks or cesium clocks.

5. A voltage reference remote calibration method based on the voltage reference remote calibration system according to claim 1, characterized in that: The following steps are involved: When the calibrated integrated circuit test system issues a calibration request, the relationship between the frequency signal and the standard voltage signal in the calibration key is updated; The updated calibration key is transmitted to the calibrated integrated circuit test system, the calibration key is inserted into the calibration board, a frequency signal is provided to the calibration key through the calibration board, the frequency signal is converted into a voltage signal through the calibration key, and the standard voltage signal output by the calibration key is obtained through a multimeter; at the same time, the integrated circuit test system outputs a test voltage signal; The test voltage signal is compared with the standard voltage signal, and the integrated circuit test system's own benchmark is measured based on the difference between the two.

6. The voltage reference remote calibration method according to claim 5, characterized in that: The chip conversion circuit in the calibration key is chip AD650. When chip AD650 is packaged for heat preservation and magnetic field resistance, the pins of chip AD650 are exposed.

7. The voltage reference remote calibration method according to claim 6, characterized in that: The chip AD650 is inserted into the calibration board by connecting the chip pins of the chip AD650 with the chip fixture on the calibration board.

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