JP2000206179A - Method and device for inspecting characteristic of electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an inspection device to carry out accurate inspection by making a specific current flow between the measuring terminals of an inspecting device and the lead wire of an electronic component, reducing the contact resistance between the measuring terminals and the lead wire, and impressing voltage for characteristic inspection. SOLUTION: The measuring terminals S1-S2 of the characteristic inspecting test device are brought into contact with the lead wire 1a of a reed-type electronic component DUT such as a diode, and the measuring terminals S3-S4 of the inspecting test device are brought into contact with the lead wire 1b. For inspecting the contact state between the measuring terminals S1 and S2 and the lead wire 1a, the movable contacts of relays RY11-RY14 are brought into contact with a fixed contact (a) and are turned in mode 1. Then, when a switch SW1 is turned on, inspecting current 11 is passed in a path from a power source E1 to a resistance R1, the relay RY13, the measuring terminal S1, the lead wire 1a, the measuring terminal S2, the relay RY14, and the switch SW1. The inspecting current 11 is in a range of 10-30A for reducing the contact resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention measures the contact resistance between a measuring terminal of an inspection device and a lead wire of an electronic component in advance when inspecting characteristics of an electronic component such as a diode and a resistor, and improves the contact state. The present invention relates to a method and an apparatus for inspecting characteristics of an electronic component in which an original characteristic inspection is carried out after that.

[0002]

2. Description of the Related Art A method of inspecting characteristics of an electronic component of this kind will be described with reference to FIG. In the figure, the DUT is a lead-type electronic component, and here shows a diode.

The measuring terminals D1, D2 and D3, D4 of the inspection device are brought into contact with the lead wires 1a, 1b of the DUT, respectively. Further, relays RY1 to RY4 each having a movable contact for switching to each of the measurement terminals D1 to D4 and fixed contacts a and b are connected as shown.
That is, the measurement terminal D1 has the relay RY1 and the measurement terminal D
2, a relay RY2, a measurement terminal D3 a relay RY3,
The relay RY4 is connected to the measurement terminal D4. Here, the case where the movable contacts of all the relays RY1 to RY4 are connected to the fixed contact a is referred to as mode 1, and
The movable contacts of all relays RY1 to RY4 are fixed contacts b
The mode when the connection is made to mode 2 is mode 2. In the case of the mode 1, the measuring terminals D1 and D3 are connected to the DC power supply E, respectively.
1 and E2, and the other measurement terminals D2 and D4 are connected to photocouplers PC1 and PC2 via resistors R1 and R2, respectively.

[0004] In the above configuration, prior to the original characteristic inspection of the DUT, first, the contact state between the DUT and the measurement terminals D1 to D4 of the characteristic inspection device is inspected. That is, in the circuit configuration as described above, the switches SW1 and SW2
Is turned on, and the measurement terminals D1 and D2 on the DC power supply E1 side
When contacting the lead wire 1a of the UT, the photocoupler P
A current flows through C1 via the resistor R1, and the transistor C1 is turned on. In this case, the measurement terminals D1, D2 and the lead wire 1
A signal indicating that the contact state with a is OK is extracted.

On the other hand, when the measuring terminals D1 and D2 are not in contact with the lead wire 1a, no current flows from the DC power supply E1 to the photocoupler PC1. In such a case, the photocoupler PC1 is turned off and the measuring terminal D
1, a signal is taken out of which the contact state between the lead wire 1a and D2 is NG. Similarly, on the DC power supply E2 side, the contact state between the measurement terminals D3 and D4 and the lead wire 1b can be visually confirmed by blinking of the photocoupler PC2.

Next, when it is confirmed that the measuring terminal and the lead wire are in contact with each other on both the lead wire 1a side and the lead wire 1b side, all the relays are connected to the fixed contact b by means not shown. Mode 2 is set. At this time, the switch SW3 is turned on, and the DC power source E3 connects the measuring terminal D
1, a current for characteristic inspection flows to the DUT via D3. Then, the voltage across the DUT is measured by the voltmeter VF via the measurement terminals D2 and D4 by the current flowing through the DUT.

[0007]

Prior to the original characteristic inspection, the contact state between the lead wires 1a and 1b and the measuring terminals D1 to D4 has been conventionally inspected by the above-described method. That is, the contact state is determined based on whether or not a very small current in the range of 10 to 100 mA actually flows, and the magnitude of the actual contact resistance between the measurement terminals D1 to D4 and the leads 1a and 1b is ignored. It was an inspection method. In the inspection method as described above, even if the measuring terminals D1 to D4 are the lead wires 1a and 1b
Even if it is in contact with the electronic component, when the electronic component to be inspected is replaced and brought into contact each time, the contact resistance at that time differs each time. For example, when the contact resistance is large, the original test current of about 50 to 200 A flows instantaneously. In this case, a spark is generated between the measuring terminals D1 to D4 and the lead wires 1a and 1b, and the measuring terminals D1 to D4 and the lead wires 1a and 1b are melted. was there.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to inspect a contact resistance value between a measurement terminal of a characteristic inspection device and lead wires 1a and 1b of a lead-type electronic component DUT. And a characteristic inspection method and characteristic inspection of an electronic component in which the contact state between the measurement terminals D1 to D4 and the lead wire is improved by the inspection current I1 of the contact resistance value so that the original characteristic inspection can be performed accurately. It is intended to provide a device.

[0009]

According to a first aspect of the present invention, a measuring terminal of an inspection device is brought into contact with a lead wire of a lead-type electronic component,
In a method of inspecting characteristics of an electronic component by applying a voltage or flowing a current, a predetermined current is passed between a measurement terminal of the inspection device and a lead wire of the electronic component, and the measurement terminal is connected to the electronic terminal. After the contact resistance between the lead wires of the component is reduced, a voltage for characteristic inspection is applied or a current is passed to inspect the characteristic of the electronic component.

A second invention is characterized in that the current for reducing the contact resistance flowing between the measuring terminal of the inspection device and the lead wire of the electronic component is in the range of 10 to 30 A. .

A third aspect of the present invention relates to one lead wire 1 of a DUT.
a, a test power supply E1 connected to the terminals S1, S2 via relays RY13, RY14, the one lead wire 1a and the terminals S1, S2
A voltmeter VR1 for measuring a contact resistance with the DUT 2 and the DUT
Measuring terminals S3, S4 in contact with the other lead wire 1b of
An inspection power source E2 connected to the terminals S3 and S4 via relays RY17 and RY18, and the other lead wire 1b;
Voltmeter V for measuring the contact resistance between the terminals S3 and S4
R2, a test power source E3 connected between the measurement terminals S1 and S4 via relays RY11 and RY18, and a relay R connected to the measurement terminals S2 and S3.
Test voltmeter VF connected via Y12 and RY17
It is characterized by having.

[0012]

An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, the DUT is a lead-type electronic component such as a diode. The measurement terminals S1 and S2 of the characteristic test device are brought into contact with the lead wire 1a of the DUT, and the measurement terminals S3 and S4 of the test device are brought into contact with the lead wire 1b.

The relays RY11 and RY1 are connected to the measuring terminal S1.
3, a measurement terminal S2 is connected to relays RY12 and RY14, respectively, and a voltmeter VR1 for measuring a voltage described later is connected between fixed contacts a and a of the relays RY11 and RY12. Relays RY13 and RY14
A power source E1 for supplying the inspection current I1 is connected between the fixed contacts a.

The relays RY15 and RY1 are connected to the measuring terminal S3.
7, a relay RY16, RY18 is connected to the measuring terminal S4, respectively, and a voltmeter V for measuring a voltage described later is provided between fixed contacts a, a of the relays RY15 and RY16.
R2 is connected. Also, the relays RY17 and RY
A power supply E2 for flowing the inspection current I1 is connected between the fixed contacts 18 of the 18.

Further, a power supply E3 for supplying a test current IS is connected between the fixed contact b of the relay RY11 and the fixed contact b of the relay RY18 via a resistor R3 and a switch SW3. Further, a voltmeter VF for measuring a voltage described later is connected between the fixed contact b of the relay RY12 and the fixed contact b of the relay RY17. The relay RY1
Nothing is connected to the fixed contacts b of 3, RY14, RY15, and RY16.

In the above configuration, the measuring terminals S1 and S1
In order to check the contact state between the lead 2 and the lead wire 1a, the movable contacts of the relays RY11, RY12, RY13, and RY14 are brought into contact with the fixed contact a to set the mode 1 to the state. Next, when the switch SW1 is turned on, a resistor R1, a relay RY13, a measurement terminal S1, a lead wire 1a,
An inspection current I1 flows through the path of the measurement terminal S2, the relay RY14, and the switch SW1. Note that the inspection current I1 was in the range of 10 to 30 A in this embodiment.

The current values in the above ranges are particularly significant in the present invention. That is, even if the surface of the lead wires 1a and 1b is stained, the mold burr formed during resin molding adheres, and the contact with the measurement terminal is incomplete, the inspection current I1 in the above-mentioned range is applied to cause a partial minute spark. To improve contact. On the other hand, it has been found from various experimental results that contact is not completed with a current smaller than this range, and a large spark is generated with a current larger than this range, and the measurement terminals and the lead wires are welded. Therefore, the above range of the current value is preferable.

At the same time that the inspection current I1 is supplied from the power supply E1, the voltage between the measurement terminals S1 and S2 is measured by a voltmeter VR1, and if the current value is within a specified value, the contact resistance is small and the contact state is low. It shows that it is good.

Here, the voltage measured by the voltmeter VR1 when the inspection current I1 flows is vr1, and this vr1 will be considered. In the case shown, the resistance of the wiring L1 is Ra, the resistance of the portion corresponding to the length Lo of the lead wire 1a is Rc, the resistance of the wiring L2 is Rb, and the contact resistance between the measurement terminal S1 and the lead wire 1a is Assuming that Rd is the contact resistance Re between the measurement terminal S2 and the lead wire 1a, the voltage vr1 is expressed by the following equation. vr1 = I1 * (Ra + Rb + Rc + Rd + Re) (1)

If Ra, Rb, and Rc are measured and found in advance in the above equation (1), vr1 measured in mode 1 in FIG.
By subtracting I1 * (Ra + Rb + Rc) from the above, the contact resistance components Rd and Re can be found.

On the lead wire 1b side, the contact resistance of the measuring terminals S3 and S4 is determined in the mode 1 in the same manner as described above. Although not shown, the numerical values vr1 and vr2 measured by the voltmeter VR1 and the voltmeter VR2 are stored and held by known means. Then, VR1 = I1 *
If (Rd + Re) is larger than the specified value, the diode to be inspected is removed from the measuring station before entering the mode 2 described below.

On the other hand, vr1, vr2 of the diode under test
Is the specified value, the next mode is entered. Then, the switches RY11 to RY are turned off after the switches SW1 and SW2 are turned off.
All 18 fixed contacts a are switched to the fixed contact b side. That is, the fixed contacts b of the relays RY11 and RY18
Is connected to a power supply E3 for supplying a test current via a relay, and connected to a voltmeter VF for measuring a voltage drop of a diode by relays RY12 and RY17.

In the case of the mode 2, the switch SW3 is turned on, and a current of 50 to 200 A flows from the power supply E3 to the diode as the test current IS. This current value is determined by the type of diode. The test current IS
Is measured by the voltmeter VF. If the current value is within the specified value, the current value is stored and held as a non-defective product.

When the test is completed, the switch SW
3 is turned off and the diode is transported to the next station. Further, all the relays RY11 to RY18 also return to the mode 1. The power supplies E1, E2, and E3 are all constant current power supplies.

As described above, in the present invention, unlike the conventional inspection current of 10 to 100 mA for inspecting the contact resistance,
It is characterized in that it is increased to 10 to 30 A. However, if it is 10 A or less, it is not effective for removing foreign substances and the like on the contact surface described later, and it is intended to minimize damage to the product to be inspected. 30A or less.

That is, in the prior art, since the lead wires 1a and 1b and the measuring terminals D1 to D4 are slightly in contact with each other and a current flows even if the contact resistance is large, a spark is generated by a test current which flows during an original characteristic current test. Was occurring. Therefore, in the present invention, a relatively large current in the range of 10 to 30 A is applied at an initial stage to check the contact resistance, and the contact state is satisfactorily improved by the current.

The magnitude of the first current to be passed is specifically determined based on the size of the terminal of the product to be inspected, the magnitude of the original test current, and the like. As a result, the lead wires 1a,
1b, the measurement terminal S
Even if they are interposed between 1, S2, S3 and S4, the contact state between them becomes good, and sparks and the like do not occur as in the prior art.

Although the above embodiment has been described using a diode as the DUT, the present invention can be applied to other elements such as an axial lead type electronic component. Also, the relays RY11 to RY18 and the switches SW1 to S shown in FIG.
W3 may be replaced by an electronic element.

[0029]

As described above, the characteristic inspection method and the characteristic inspection apparatus for an electronic component of the present invention first determine the current for inspecting the contact resistance in the range of 10 to 30 A and compare it with the conventional method. Since the current value was increased, lead wire 1
It is possible to remove dirt on the contact surfaces between the a and 1b and the measuring terminals S1 and S2, that is, thin burrs and adhesion of solder flux at the time of molding. This makes it possible to accurately carry out the original characteristic test in a good contact state. Further, prior to conducting the original characteristic test, the lead wires 1a, 1
By measuring the contact resistance between b and the measurement terminals S1, S2, S3 and S4, if the contact resistance is extremely large, the subsequent characteristic test can be stopped. As a result, there is an effect that it is possible to eliminate damage due to wear of the measuring terminal, spark of the lead wire, and the like.

[Brief description of the drawings]

FIG. 1 is a circuit diagram for carrying out an electronic component characteristic inspection method according to an embodiment of the present invention.

FIG. 2 is a circuit diagram for implementing a conventional method for inspecting characteristics of electronic components.

[Explanation of symbols]

 DUT Lead type electronic component 1a, 1b Lead wire S1 to S4 Measurement terminal RY11 to RY18 Relay E1 to E3 Constant current power supply VR1, VR2 Voltmeter VF Voltmeter

Claims (3)

[Claims] 1. A characteristic inspection method for an electronic component in which a measurement terminal of an inspection device is brought into contact with a lead wire of a lead-type electronic component and a characteristic is applied to the electronic component by applying a voltage or flowing a current. A predetermined current is passed between the measurement terminal and the lead wire of the electronic component, and a voltage for characteristic inspection is applied after reducing the contact resistance between the measurement terminal and the lead wire of the electronic component, or the current is passed. A characteristic inspection method for an electronic component, wherein the characteristic of the electronic component is inspected. 2. The electronic device according to claim 1, wherein a current for reducing a contact resistance flowing between a measurement terminal of the inspection device and a lead wire of the electronic component is in a range of 10 to 30 A. Inspection method for component characteristics. 3. Measurement terminals S1 and S2 that are in contact with one lead wire 1a of a lead-type electronic component DUT, and the terminals S1 and S2.
Inspection power supply E1 connected to relay 2 via relays RY13, RY14, one lead wire 1a and terminal S
A voltmeter VR1 for measuring the contact resistance with the SUT 1 and S2, and a measuring terminal S in contact with the other lead wire 1b of the DUT.
3, S4 and the relays RY17, RY1 to the terminals S3, S4.
8, a voltmeter VR2 for measuring the contact resistance between the other lead wire 1b and the terminals S3 and S4, and between the measuring terminal S1 and the measuring terminal S4. Relay R
A test power supply E3 connected via Y11 and a relay RY18, and relays RY12, R3 connected to the measurement terminals S2, S3.
A characteristic inspection device for an electronic component, comprising: a test voltmeter VF connected via Y17.