TWM621317U - Small current measuring alignment bracket mechanism for integrated circuit automatic test machine - Google Patents

Abstract

The utility model discloses a small current measurement and calibration structure for an integrated circuit automatic testing machine, which comprises a DC correction board, a voltmeter and an external control system; the DC correction board is connected with the integrated circuit automatic testing machine to form a channel, A reference resistor is connected in series on the path; the voltmeter is connected in parallel with the reference resistor to measure the voltage across the reference resistor; the external control system is respectively connected with the digital multimeter and the electromechanical signal of the automatic test of the integrated circuit, which is used for the automatic tester of the integrated circuit. When the test signal is generated, the integrated circuit automatic testing machine is in the test state, and at the same time, the signal sent by the voltmeter is acquired and processed to obtain the current measured value, and the current measured value is compensated to obtain the current output value. The utility model overcomes the defect of numerical distortion caused by magnetic field interference in the prior art, and realizes accurate measurement of small current of an integrated circuit automatic testing machine by introducing a reference resistance and measuring voltage; the utility model has simple structure, low cost and good application prospect.

Description

A small current measurement calibration frame for integrated circuit automatic testing machine structure

The utility model belongs to the technical field of small current measurement of an integrated circuit automatic testing machine, and relates to a small current measurement and calibration framework for an integrated circuit automatic testing machine.

Integrated Circuit Automatic Test Equipment (Automatic Test Equipment) in the semiconductor industry means integrated circuit (IC) automatic test machine, which is used to test the functional integrity of integrated circuits. The quality of body circuit manufacturing.

In the calibration process of the integrated circuit automatic testing machine, the measurement of small current is a very important task. The current test current is shown in Figure 1 (including the ammeter 11, the DC calibration board 12, the external control system 13 and the integrated circuit). As shown in the automatic testing machine 14), it directly uses a digital multimeter to directly test the current. This test method is more suitable for measuring large currents, because compared with large currents, electric field interference and other such problems are The interference energy is small, and it is difficult to affect the measurement of large currents, but for small currents of uA and nA levels, the impact of these interference energies is relatively large, and this noise floor may drown out weaker small currents. Interfering energy is superimposed into the circuit, which can easily lead to distortion of the measured data.

Therefore, it is of great practical significance to develop a device capable of accurately measuring the small current of the integrated circuit automatic testing machine 14 .

The purpose of the utility model is to overcome the defect that the conventional technology cannot guarantee the authenticity of the measurement data, and to provide a device that can accurately measure the small current of an integrated circuit automatic testing machine.

In order to achieve the above purpose, the present utility model provides the following technical solutions: a small current measurement and calibration framework for an integrated circuit automatic testing machine, including a DC correction board, a voltmeter and an external control system; the DC correction board and the integrated circuit The circuit automatic testing machine is connected to form a channel, and the reference resistance is connected in series on the channel; the voltmeter is connected in parallel with the reference resistance to measure the voltage at both ends of the reference resistance; the external control system is respectively connected with the digital multimeter and the integrated circuit The automatic test electromechanical signal connection is used to generate a test signal to the integrated circuit automatic testing machine to make the integrated circuit automatic testing machine test state, and at the same time acquire and process the signal sent by the voltmeter, obtain the current measured value, and make the current measured value. Compensation is performed to obtain the current output value. The compensation of the current measured value by the external control system is realized by comparing the difference between the measured value and the standard value, and this part is the same as the compensation technology of the prior art.

The structure of the conventional technology is shown in Figure 1. When measuring small currents, it is necessary to use a measuring wire to connect the ammeter 11 to the circuit. During the measurement, the measuring wire has a current passing through it, and there will be a A large number of magnetic fields are generated, and the energy of these disturbances can be added to the circuit, causing numerical distortion.

The small current measurement and calibration framework of the utility model for the integrated circuit automatic testing machine adopts the method of curve test, introduces a reference resistance to measure the small current, and converts the voltage at both ends of the reference resistance into current. Distortion problems during current testing, do To ensure the accuracy of the measurement and reduce the requirements of the test environment, on the other hand, by selecting a reference resistor with a larger resistance value, it can be processed similar to amplification to increase the signal-to-noise ratio and enhance the anti-interference ability. The utility model realizes the accurate measurement of the small current of the integrated circuit automatic testing machine, and has simple structure, low cost and great application prospect.

As a preferred technical solution: the above-mentioned small current measurement and calibration structure for an integrated circuit automatic testing machine, the reference resistor is located on the DC calibration board. The protection scope of the present invention is not limited to this, and only a feasible technical solution is provided here. At the same time, a DC correction circuit is provided on the DC correction board, wherein the DC correction circuit is a conventional technology.

In the above-mentioned low-current measurement and calibration architecture for an integrated circuit automatic testing machine, the external control system is an industrial computer (IPC).

In the above-mentioned small current measurement and calibration framework for an integrated circuit automatic testing machine, the voltmeter is a digital multimeter. The protection scope of the present invention is not limited to this, only a feasible technical solution is given here, and other devices capable of measuring voltage can be applied to the present invention.

The above-mentioned small current measurement and calibration framework for an integrated circuit automatic testing machine, the _{calculation formula of the current measured value I real} is as follows: I _real =U _real /R; U _real is the reading of the voltmeter, and the unit is is V; R is the resistance value of the reference resistor, the unit is Ω.

A low-current measurement and calibration structure for an integrated circuit automatic testing machine as described above, the measurement of the reference resistance adopts the Kelvin Four-terminal sensing method (also known as the four-wire circuit measurement method) This method can prevent the influence of parasitic resistance on the measured value. The Kelvin four-wire detection method is a relatively mature method in the field of circuit detection. The key advantage of the test method is the separation of the current and voltage electrodes, eliminating the impedance of wiring and contact resistance.

Beneficial effects: (1) The small current measurement and calibration framework for the integrated circuit automatic testing machine of the present invention overcomes the defect of numerical distortion caused by the magnetic field interference of the prior art, and realizes the small current of the integrated circuit automatic testing machine. Accurate measurement; (2) The small current measurement and calibration framework for the integrated circuit automatic testing machine of the present invention introduces a reference resistor to measure a small current, and converts the voltage at both ends of the reference resistor into current, which solves the problem on the one hand. The distortion problem in the process of small current test ensures the accuracy of the measurement and reduces the requirements of the test environment. Anti-interference ability; (3) The small current measurement and calibration framework for the integrated circuit automatic testing machine of the present invention has the advantages of simple structure, low cost and great application prospect.

11: Ammeter

12,22: DC correction board

13: External control system

14: Integrated circuit automatic testing machine

21: Voltmeter

25: Reference resistance

FIG. 1 is a small current measurement and calibration structure of an automatic integrated circuit testing machine in the prior art; and FIG. 2 is a small current measurement and calibration structure of an integrated circuit automatic testing machine of the present invention.

The specific embodiments of the present utility model will be further described below with reference to the accompanying drawings.

Example 1

A small current measurement and calibration architecture for an integrated circuit automatic testing machine 14, as shown in FIG. 2, includes a DC calibration board 22, a voltmeter 21 (specifically a digital multimeter) and an external control system 13 (specifically, an industrial computer) The DC correction plate 22 is connected with the integrated circuit automatic testing machine 14 to form a path, and the reference resistance 25 is connected in series on the path (the reference resistance 25 is located on the DC correction board 22); the voltmeter is connected in parallel with the reference resistance 25 for measuring the reference The voltage at both ends of the resistor 25 is specifically measured by the Kelvin four-wire detection method (also known as the four-wire circuit measurement method) to measure the voltage at both ends of the reference resistor 25; the external control system 13 is connected with the digital multimeter and the integrated circuit automatic testing machine 14 respectively. The electrical signal connection is used to generate a test signal to the integrated circuit automatic testing machine 14 so that the integrated circuit automatic testing machine 14 is in a test state, and at the same time acquire and process the signal sent by the voltmeter, obtain the current measured value I _real , and measure the current The measured value is compensated to obtain the current output value. The calculation formula of the _{current measured value I real is as follows: I real} =U _real /R; U _real is the reading of the voltmeter, the unit is V; R is the resistance value of the reference resistor 25, The unit is Ω.

It has been verified that the small current measurement and calibration framework for the integrated circuit automatic testing machine 14 of the present invention overcomes the defect of numerical distortion caused by magnetic field interference in the prior art, and realizes the accuracy of the small current of the integrated circuit automatic testing machine 14. Measurement: The reference resistor 25 is introduced to measure a small current, and the voltage across the reference resistor 25 is converted into a current. On the one hand, it solves the distortion problem during the small current test, ensures the accuracy of the measurement, and reduces the requirements of the test environment. On the one hand, the reference resistor 25 with a larger resistance value can be selected to perform similar amplification processing to increase the signal. Noise ratio, enhance anti-interference ability; simple structure, low cost, great application prospects.

Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these are only examples, and various changes can be made to these embodiments without departing from the principles and essence of the present invention. or modified.

13: External control system

14: Integrated circuit automatic testing machine

21: Voltmeter

22: DC correction board

25: Reference resistance

Claims (6)

A small current measurement and calibration framework for an integrated circuit automatic testing machine, comprising a DC correction board, a voltmeter and an external control system; The DC calibration board is connected with the integrated circuit automatic testing machine to form a path, and a reference resistor is connected in series on the path; The voltmeter is connected in parallel with the reference resistor for measuring the voltage across the reference resistor; The external control system is respectively connected with the digital multimeter and the electromechanical signal of the automatic test of the integrated circuit, and is used for generating the test signal to the automatic tester of the integrated circuit, so that the automatic tester of the integrated circuit is in a test state, and at the same time obtains and processes the output of the voltmeter. signal, obtain the current measured value, and compensate the current measured value to obtain the current output value. The small current measurement calibration architecture for an integrated circuit automatic testing machine of claim 1, wherein the reference resistor is located on a DC calibration board. The low-current measurement calibration architecture for an integrated circuit automatic testing machine according to claim 1, wherein the external control system is an industrial computer. The small current measurement calibration framework for an integrated circuit automatic testing machine of claim 1, wherein the voltmeter is a digital multimeter. As claimed in claim 1, the low-current measurement and calibration framework for an integrated circuit automatic testing machine, wherein the _{calculation formula of the current measured value I real} is as follows: I _real =U _real /R; U _real is the reading of the voltmeter, The unit is V; R is the resistance value of the reference resistor, the unit is Ω. The low-current measurement calibration architecture for an integrated circuit automatic testing machine according to claim 1, wherein the measurement of the reference resistance is performed using a Kelvin four-wire detection method.

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