A calibration method and system for DC current measurement parameters

Abstract

The present invention provides a calibration method and system for DC current measurement-related parameters, including: connecting the calibration interface of the calibration device to the traceability interface of the traceability board; connecting the DC standard ammeter and the DC signal source to the connection terminals of the traceability board; establishing a connection between the connection terminals of the traceability board and the DC signal source and the DC standard ammeter in series through a connection cable; controlling the calibration device and the DC standard ammeter to enter the DC current measurement mode, and controlling the DC signal source to output a preset DC voltage signal; obtaining a first measurement value of the calibration device and obtaining a second measurement value of the DC standard ammeter to obtain the measurement error of the calibration device at the current calibration point; tracing the quantity value of the calibration device based on the measurement error, and using the calibrated calibration device to calibrate the DC current measurement-related parameters of the integrated circuit test system. The present invention comprehensively and truly reflects the overall technical indicators of the DC current measurement-related parameters of the calibration device.

Description

Technical Field

[0001] The present invention belongs to the technical field of microelectronic test and measurement, and more specifically, relates to a calibration method and system for DC current measurement parameters. Background Art

[0002] The DC current measurement parameters of an integrated circuit test system (referred to as the test system for short) include parameters such as PMU current measurement and DPS current measurement.

[0003] Currently, the calibration of the DC current measurement parameters of the test system is mainly achieved by developing and establishing an integrated circuit test system calibration device (referred to as the calibration device for short). The calibration device includes a calibration board and an external instrument. During calibration, the calibration board is loaded onto the test system, and the external instrument is connected to the loaded board. The external instrument is controlled to measure various DC current measurement parameters of the test system to complete the calibration. This method has an ideal effect on transferring the quantity values of the DC current measurement parameters of the calibration device to the test system.

[0004] However, there is currently no dedicated method for the upward traceability of the quantity values of the DC current measurement parameters of the calibration device. Usually, only the external instruments that make up the calibration device are sent to the metrology technical institution separately to complete the quantity value traceability at the instrument level. However, other components of the calibration device, such as matrix switches, various cables, interfaces, calibration software, etc., will all affect the calibration results. The influence of these components on the measurement uncertainty of the DC current measurement parameters of the test system calibration device can reach more than 20%. It can be seen from this that these components are non-negligible sources of uncertainty and are the main influencing quantities of uncertainty. Therefore, the true technical indicators of the calibration device cannot be directly obtained from the technical indicators of the external instruments. The overall technical indicators of the DC current measurement parameters of the calibration device have not been comprehensively and truly reflected during the process of quantity value traceability. Summary of the Invention

[0005] Aiming at the defects of the prior art, the purpose of the present invention is to provide a calibration method and system for DC current measurement parameters, aiming to solve the problem that the overall technical indicators of the DC current measurement parameters of the existing calibration device have not been comprehensively and truly reflected during the process of quantity value traceability, and it is impossible to perform ideal and reliable calibration on the DC current measurement parameters of the integrated current test system.

[0006] To achieve the above purpose, in the first aspect, the present invention provides a calibration method for DC current measurement parameters, especially for an integrated circuit test system, including the following steps:

[0007] Step 1, respectively connect the positive and negative poles of the calibration interface of the calibration device to the positive and negative poles of the traceability interface of the traceability board in a corresponding manner;

[0008] Step 2: Connect the positive pole of the connection terminal of the traceability board to the negative pole of the DC standard ammeter, the positive pole of the DC standard ammeter to the positive pole of the DC signal source, and the negative pole of the DC signal source to the negative pole of the connection terminal; the DC current measurement uncertainty of the DC standard ammeter is less than or equal to one-third of the DC current measurement uncertainty of the calibration device; the negative pole of the connection terminal is connected to the negative pole of the traceability interface, and the positive pole of the connection terminal is connected to the positive pole of the traceability interface;

[0009] Step 3: Control the calibration device and the DC standard ammeter to enter the DC current measurement mode, and control the DC signal source to output a preset DC voltage signal; the DC voltage signal is related to the value of the current calibration point of the calibration device;

[0010] Step 4: Obtain the measurement value of the traceability interface obtained by the calibration device when measuring the DC current signal on the traceability interface side, and obtain the measurement value of the ammeter obtained by the DC standard ammeter when measuring the DC current signal;

[0011] Step 5: Compare the measurement value of the traceability interface with the measurement value of the ammeter to obtain the measurement error of the calibration device at the current calibration point;

[0012] Step 6: Use the measurement error to trace the quantity value of the DC current measurement type parameters of the calibration device, and calibrate the DC current measurement type parameters of the integrated circuit test system based on the calibrated calibration device.

[0013] In an optional example, the current measurement range of the DC standard ammeter covers the current measurement range of the calibration device; the DC voltage output range of the DC signal source should be able to meet the traceability requirements of the DC current measurement type parameters of the calibration device.

[0014] In a second aspect, the present invention provides a calibration system for DC current measurement type parameters of an integrated circuit test system, characterized in that the calibration system includes: a traceability board;

[0015] The traceability board includes a connection terminal and a traceability interface, wherein the negative pole of the connection terminal is connected to the negative pole of the traceability interface, and the positive pole of the connection terminal is connected to the positive pole of the traceability interface;

[0016] The traceability interface of the traceability board is connected to the calibration interface of the calibration device, wherein the positive pole of the traceability interface is connected to the positive pole of the calibration interface, and the negative pole of the traceability interface is connected to the negative pole of the calibration interface;

[0017] The connection terminals of the traceability board are connected to a DC standard ammeter and a DC signal source; among them, the positive pole of the connection terminal is connected to the negative pole of the DC standard ammeter, the positive pole of the DC standard ammeter is connected to the positive pole of the DC signal source, and the negative pole of the DC signal source is connected to the negative pole of the connection terminal; the DC current measurement uncertainty of the DC standard ammeter is less than or equal to one-third of the DC current measurement uncertainty of the calibration device; the DC standard ammeter and the DC signal source are used to trace the quantity value of the DC current measurement parameters of the calibration device, and the tracing process is as follows: control the calibration device and the DC standard ammeter to enter the DC current measurement mode, and control the DC signal source to output a preset DC voltage signal, and the DC voltage signal is related to the value of the current calibration point of the calibration device; then obtain the traceability interface measurement value obtained by the calibration device measuring the DC current signal on the traceability interface side, and obtain the ammeter measurement value obtained by the DC standard ammeter measuring the DC current signal, compare the traceability interface measurement value with the ammeter measurement value, and obtain the measurement error of the calibration device at the current calibration point; based on the measurement error, trace the quantity value of the DC current measurement parameters of the calibration device.

[0018] The calibrated device after quantity value traceability is used to calibrate the DC current measurement parameters of the integrated circuit test system.

[0019] In an optional example, the traceability board is a PCB board; the positive and negative poles of the connection terminal and the traceability interface are respectively connected through PCB traces.

[0020] In an optional example, the current measurement range of the DC standard ammeter covers the current measurement range of the calibration device; the DC voltage output range of the DC signal source should be able to meet the traceability requirements of the DC current measurement parameters of the calibration device.

[0021] Generally speaking, compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:

[0022] The present invention provides a calibration method and system for DC current measurement parameters, which has the following advantages: (1) The quantity value traceability is completely based on the normal calibration process of the DC current measurement parameters of the calibration device. The external instruments, cables, and calibration software of the calibration device are configured completely according to the normal calibration process, which can reflect the technical indicators of the calibration device under the actual calibration working conditions, comprehensively and truly reflect the overall technical indicators of the DC current measurement parameters of the calibration device, and can perform ideal and reliable calibration on the DC current measurement parameters of the integrated current test system; (2) The calibration device can realize the traceability of the DC current measurement parameters of the calibration device without any software and hardware adjustment, reducing the cost of adapting the calibration device. Description of the Drawings

[0023] Figure 1Flowchart of a calibration method for DC current measurement - related parameters provided by an embodiment of the present invention;

[0024] Figure 2 Structural diagram of a calibration system for DC current measurement - related parameters provided by an embodiment of the present invention;

[0025] Figure 3 Another flowchart of a calibration method for DC current measurement - related parameters provided by an embodiment of the present invention. Detailed implementation manners

[0026] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part rather than all of the embodiments of the present invention. The description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0027] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments of the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of the described features, steps, operations, devices, components and / or their combinations.

[0028] Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for the sake of description, the sizes of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said technologies, methods and devices should be regarded as part of the authorized specification. In all the examples shown and discussed herein, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0029] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. Without contrary explanation, these orientation words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the protection scope of the present invention: the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0030] In the description of the present invention, the meaning of "several" is more than one, the meaning of "multiple" is more than two, and understandings such as "greater than, less than, exceeding" do not include the present number, and understandings such as "above, below, within" include the present number. If there is a description of "first, second", it is only for the purpose of distinguishing technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0031] In the description of the present invention, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0032] In order to solve the problems that there is no dedicated method for the upward traceability of the measured values of DC current measurement-related parameters of the current calibration device, only the external instruments that make up the calibration device are sent to the metrology technical institution separately to complete the traceability of the measured values at the instrument level, and the technical indicators of the overall calibration device are not comprehensively and truly reflected in the process of traceability of the measured values, etc., a traceability method for DC current measurement-related parameters of an integrated circuit test system calibration device is proposed.

[0033] The present invention is completely based on the calibration process of the calibration device. The external instruments, cables, and calibration software of the calibration device are configured completely according to the normal calibration process. On the basis of ensuring that the accuracy of the measurement results meets the requirements of traceability of the measured values, it can reflect the technical indicators of the DC current measurement-related parameters of the calibration device under the actual calibration working conditions, and no software or hardware adjustment is required at the calibration device end.

[0034] Figure 1 It is a flowchart of a calibration method for DC current measurement-related parameters provided by an embodiment of the present invention; as Figure 1 shown, it includes the following steps:

[0035] Step 1: Connect the positive and negative poles of the calibration interface of the calibration device to the positive and negative poles of the traceability interface of the traceability board respectively;

[0036] Step 2: Connect the positive pole of the connection terminal of the traceability board to the negative pole of the DC standard ammeter, connect the positive pole of the DC standard ammeter to the positive pole of the DC signal source, and connect the negative pole of the DC signal source to the negative pole of the connection terminal; the measurement uncertainty of the DC current of the DC standard ammeter is less than or equal to one-third of the measurement uncertainty of the DC current of the calibration device; the negative pole of the connection terminal is connected to the negative pole of the traceability interface, and the positive pole of the connection terminal is connected to the positive pole of the traceability interface;

[0037] Among them, the connection relationships of the calibration device, the traceability board, the DC standard ammeter and the DC signal source are referred to Figure 2 as shown.

[0038] Step 3: Control the calibration device and the DC standard ammeter to enter the DC current measurement mode, and control the DC signal source to output a preset DC voltage signal; the DC voltage signal is related to the value of the current calibration point of the calibration device;

[0039] Step 4: Obtain the measurement value of the traceability interface measured by the calibration device for the DC current signal on the traceability interface side, and obtain the measurement value of the ammeter measured by the DC standard ammeter for the DC current signal;

[0040] Step 5: Compare the measurement value of the traceability interface with the measurement value of the ammeter to obtain the measurement error of the calibration device at the current calibration point;

[0041] Step 6: Trace the quantity value of the DC current measurement-related parameters of the calibration device by using the measurement error, and calibrate the DC current measurement-related parameters of the integrated circuit test system based on the calibrated calibration device.

[0042] Specifically, referring to Figure 2 , taking the PMU current measurement of the calibration device of the integrated circuit test system with 50 calibration interface channels as an example to illustrate the specific implementation manner of the present invention, the flowchart is shown in Figure 3 :

[0043] (1) In this embodiment, the DC signal source selects the DC signal source 5520A of Fluke Corporation. When tracing the PMU (Precision Measurement Unit) current measurement of the calibration device, it is used as a DC voltage source. Set the function of 5520A to DC voltage. Connect the positive and negative poles of the DC voltage output interface of 5520A to the positive pole of the DC standard ammeter and the negative pole of the connection terminal of the traceability board respectively through connection cables;

[0044] (2) In this embodiment, the DC standard ammeter selects the digital multimeter 3458A of Keysight Technologies. When tracing the PMU current measurement of the calibration device, it is used as a DC standard ammeter. Set the function of the 3458A to DC current. The positive and negative poles of the DC current measurement interface of the 3458A are respectively connected to the positive pole of the 5520A and the positive pole of the connection terminal of the traceability board through connecting cables, so as to form a series relationship with the 5520A at the connection terminal of the traceability board;

[0045] (3) Connect the traceability interface of the traceability board to the calibration interface of the calibration device. Through the above connection method, the DC signal source, digital multimeter, traceability board and calibration device can be connected. The DC voltage signal output by the DC signal source can be output to the calibration interface of the calibration device through the traceability board;

[0046] (4) The front of the PCB board of the traceability board is equipped with connection terminals. The connection terminals are banana plug sockets, which are used to be connected in series with the DC voltage output interface of the 5520A and the DC current measurement interface of the 3458A through banana connecting wires. The front of the PCB board is also equipped with a traceability interface. The traceability interface is an IDC50 socket, which is used to connect with the IDC50 plug of the calibration device. The connection terminals on the PCB board and the traceability interface are connected one-to-one according to the positive and negative poles through PCB traces;

[0047] (5) Control the calibration device to enter the PMU current measurement mode, and control the 3458A to enter the DC current measurement mode. Then, according to the traceability requirements of the PMU current measurement, control the 5520A to output a DC voltage parameter value. At this time, control the calibration device to measure the DC current at the traceability interface and record this value as the PMU current measurement indication value. Then keep the calibration device in the DC current measurement state, and control the 3458A to measure the DC current value at the connection terminal as the PMU current measurement standard value. Compare the standard value with the indication value to obtain the error of the PMU current measurement of the calibration device.

[0048] It can be understood that the above "indication value" should be understood as the measurement value of the traceability interface, and the "standard value" should be understood as the measurement value of the ammeter. The present invention will not make special explanations on this.

[0049] (6) Finally, the PMU current measurement of the calibration device can be corrected for errors according to the above error value, so as to ensure the reliability of the measured value of the calibration device.

[0050] Those skilled in the art can easily understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A calibration method for DC current measurement parameters, which is applicable to an integrated circuit test system, is characterized in that It includes the following steps: Step 1: Connect the positive and negative poles of the calibration interface of the calibration device to the positive and negative poles of the traceability interface of the traceability board respectively; Step 2: Connect the positive pole of the connection terminal of the traceability board to the negative pole of the DC standard ammeter, connect the positive pole of the DC standard ammeter to the positive pole of the DC signal source, and connect the negative pole of the DC signal source to the negative pole of the connection terminal; the DC current measurement uncertainty of the DC standard ammeter is less than or equal to one-third of the DC current measurement uncertainty of the calibration device; the negative pole of the connection terminal is connected to the negative pole of the traceability interface, and the positive pole of the connection terminal is connected to the positive pole of the traceability interface; Step 3: Control the calibration device and the DC standard ammeter to enter the DC current measurement mode, and control the DC signal source to output a preset DC voltage signal; the preset DC voltage signal is related to the value of the current calibration point of the calibration device; Step 4: Obtain the measurement value of the traceability interface measured by the calibration device for the DC current signal at the traceability interface side, and obtain the measurement value of the ammeter measured by the DC standard ammeter for the DC current signal; Step 5: Compare the measurement value of the traceability interface with the measurement value of the ammeter to obtain the measurement error of the calibration device at the current calibration point; Step 6: Trace the quantity value of the DC current measurement-related parameters of the calibration device by using the measurement error, and calibrate the DC current measurement-related parameters of the integrated circuit test system based on the calibrated calibration device.

2. The method according to claim 1, wherein The current measurement range of the DC standard ammeter covers the current measurement range of the calibration device; the DC voltage output range of the DC signal source should be able to meet the traceability requirements of the DC current measurement-related parameters of the calibration device.

3. A DC current measurement parameter calibration system for an integrated circuit test system, characterized in that, This calibration system includes: a traceability board; The traceability board includes a connection terminal and a traceability interface, wherein the negative pole of the connection terminal is connected to the negative pole of the traceability interface, and the positive pole of the connection terminal is connected to the positive pole of the traceability interface; The traceability interface of the traceability board is connected to the calibration interface of the calibration device, wherein the positive pole of the traceability interface is connected to the positive pole of the calibration interface, and the negative pole of the traceability interface is connected to the negative pole of the calibration interface; The connection terminals of the traceability board are connected to a DC standard ammeter and a DC signal source; among them, the positive pole of the connection terminal is connected to the negative pole of the DC standard ammeter, the positive pole of the DC standard ammeter is connected to the positive pole of the DC signal source, and the negative pole of the DC signal source is connected to the negative pole of the connection terminal; the DC current measurement uncertainty of the DC standard ammeter is less than or equal to one-third of the DC current measurement uncertainty of the calibration device; the DC standard ammeter and the DC signal source are used to trace the quantity values of the DC current measurement-related parameters of the calibration device, and the traceability process is as follows: control the calibration device and the DC standard ammeter to enter the DC current measurement mode, and control the DC signal source to output a preset DC voltage signal, and the preset DC voltage signal is related to the value of the current calibration point of the calibration device; then obtain the traceability interface measurement value obtained by the calibration device measuring the DC current signal on the traceability interface side, and obtain the ammeter measurement value obtained by the DC standard ammeter measuring the DC current signal, compare the traceability interface measurement value with the ammeter measurement value, and obtain the measurement error of the calibration device at the current calibration point; based on the measurement error, trace the quantity values of the DC current measurement-related parameters of the calibration device. The calibration device after quantity value traceability is used to calibrate the DC current measurement-related parameters of the integrated circuit test system.

4. The DC current measurement parameter calibration system according to claim 3, wherein The current measurement range of the DC standard ammeter covers the current measurement range of the calibration device; the DC voltage output range of the DC signal source should be able to meet the traceability requirements of the DC current measurement-related parameters of the calibration device.

5. The DC current measurement type parameter calibration system according to claim 3, wherein The traceability board is a PCB board; the positive and negative poles of the connection terminal and the traceability interface are respectively connected through PCB traces.

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