JPH11295385A - Apparatus for verifying contact of electronic circuit element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an apparatus for verifying the contact of an electronic circuit element of an I, etc., so that it can prevent the electronic circuit element from being broken due to overcurrent breakdown, etc. SOLUTION: Prior to various characteristic tests of an electronic circuit element, characteristics of protection diodes formed in an IC 1 under test are observed to verify the contact of the IC 1 under test to a characteristic test jig or electronic circuit element socket and other input/output terminal pins 5 than a terminal pin of the IC 1 are fixed to the level of a GND terminal 6. The drop voltage level with a reverse current flowing to the terminal under test is observed to make it possible to detect a failure, due to short-circuiting between terminals of the electronic circuit element under test at the same time as the poor contact between the element under test and characteristic test jig or electronic circuit element socket. Thus it is possible to verify the existence of the short circuit at the same time as the contact verification.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a characteristic test of an electronic circuit element such as an IC, for example, by observing the characteristic of a protection diode formed inside the electronic circuit element.
The present invention relates to an electronic circuit element contact confirmation device for confirming contact between an electronic circuit element and a test device.

[0002]

2. Description of the Related Art Conventionally, in a characteristic test of an electronic circuit element such as an IC as shown in FIG. A so-called contact test is performed. This contact test is performed by connecting a contact test circuit only to the pin to be observed of the IC under test and observing the voltage drop when a reverse current flows, as shown in FIG.

When the pin to be observed and the test jig or the IC socket are in normal contact, the voltage drop level is determined by the characteristics of the protection diode formed between each pin and GND inside the IC, as shown in FIG. It stabilizes within a certain range as shown in FIG. Conversely, in the non-contact state, the voltage drop level becomes extremely large as shown in FIG.
The quality of the contact is determined based on the voltage level. When all the pins to be observed are normally contacted, the subsequent characteristic test is continued. If one of all the pins to be observed has a non-contact state, the subsequent various characteristic tests are stopped only by the contact test, so that erroneous tests due to poor contact can be prevented beforehand. And

[0004]

However, in the conventional contact test, if there is a short circuit between the pins to be observed of the IC under test, it is difficult to detect the short-circuit by the above-mentioned contact test. Is performed in the short-circuit state between the pins to be observed, and not only is it impossible to perform an accurate test, but also there is a danger that overcurrent destruction may occur due to continuing various characteristic tests. Exists.

An object of the invention according to the present application is to provide an electronic circuit element contact confirmation device capable of preventing the destruction of an electronic circuit element such as an IC due to overcurrent destruction or the like.

[0006]

As a configuration for realizing the object of the invention according to the present application, as described in claim 1, before performing various characteristic tests of an electronic circuit device, the device is formed inside a device under test. By observing the characteristics of the protective diode, the contact between the device under test and the characteristic test jig or electronic circuit device socket is confirmed.
A terminal other than the observed terminal of the device under test is fixed at a GND level.

According to the above configuration, in the contact confirmation test for the characteristic test of the electronic circuit element, a reverse current is applied to the terminal to be observed and the voltage drop level is observed, so that the element to be tested and the characteristic test repair can be performed. At the same time as detecting a contact failure with the tool or the electronic circuit element socket, a defect due to a short circuit between terminals of the electronic circuit element under test can be detected. As described above, since it is possible to confirm the presence or absence of a short circuit at the same time as contact confirmation, in the case of a short circuit between the terminals, by not performing the subsequent characteristic test, the device under test due to overcurrent destruction or the like can be prevented. Destruction can be prevented beforehand.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIGS. 1 to 3 show an embodiment of the present invention.

FIG. 2 shows a contact confirmation device for confirming contact between the IC under test 1 and a test jig or an IC socket, and confirms whether or not terminal pins 4, 5, and 6, which are IC terminals, are in a short state. FIG. 4 is a test circuit diagram that enables

The input / output terminal pins 5 other than the observed terminal pin 4 of the IC under test 1 are connected to the GND terminal 6 together with the GND terminal 6.
It is fixed to the D level, and the current applying device 3 is connected to the observed terminal pin 4.
, A reverse current is passed through the voltmeter 2 and the voltage drop is observed. This drop voltage level is a characteristic of the protection diode between the terminal pin 4 and GND formed inside the IC 1 under test. If the drop voltage is within a certain range as shown in FIG. Will be.

On the other hand, if it is in a non-contact state, as shown in FIG. 3A, the characteristics of the protection diode do not appear, the voltage drop becomes extremely large, and it is determined that there is a defect due to the non-contact. Also, when there is a short-circuit state between the terminal pins 4, 5, and 6, the protection diode characteristic does not appear, and the voltage drop becomes extremely small as shown in FIG. .

As shown in FIG. 1, the above-described contact confirmation test is performed on all terminal pins 4 and 5 except for the GND terminal 6 of the IC 1 under test. DC characteristics test and A
Various characteristic tests, such as a C characteristic test, are performed. On the other hand, the characteristic test is stopped when a defect due to non-contact or short circuit is detected.

[0013]

According to the first aspect of the present invention, in the contact confirmation test for the characteristic test of the electronic circuit element, a reverse current is caused to flow through the terminal to be observed, and the voltage drop level is observed. This makes it possible to detect a contact failure with the characteristic test jig or the electronic circuit element socket, and at the same time, a defect due to a short circuit between the terminals of the electronic circuit element under test.
As described above, since it is possible to confirm the presence or absence of a short circuit at the same time as contact confirmation, in the case of a short circuit between the terminals, by not performing the subsequent characteristic test, the device under test due to overcurrent destruction or the like can be prevented. Destruction can be prevented beforehand.

[Brief description of the drawings]

FIG. 1 is a flowchart of an IC characteristic test according to a first embodiment of the present invention;

FIG. 2 is a configuration diagram showing a contact confirmation device according to the first embodiment of the present invention;

FIG. 3 is a graph illustrating a criterion for determining a protection diode characteristic of the contact confirmation device according to the first embodiment of the present invention;

FIG. 4 is a configuration diagram showing a contact confirmation device in a conventional example.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 IC under test 2 voltmeter 3 current applying device 4 terminal pin under observation 5 other input / output terminal pins 6 GND terminal

Claims (1)

[Claims] 1. Prior to conducting various characteristics tests of an electronic circuit element, the characteristics of a protection diode formed inside the element under test are observed to make contact between the element under test and a characteristic test jig or an electronic circuit element socket. And checking the terminals other than the observed terminal of the device under test with G
An electronic circuit element contact confirmation device fixed at an ND level.