JPH1144734A - Electronic circuit assembly testing method, testing device, and adapter for the testing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of channels of the pin electronics corresponding to the independent electric connections between an electronic circuit assembly testing device and test objects and suppress the device cost without deteriorating the performance. SOLUTION: An electronic circuit assembly testing device 1 is mounted with an electronic component 22 having a means controlling and observing the voltages of the signal pins of a boundary scan circuit, and it tests an electronic circuit assembly 21 having multiple external input/output pins 24. The electronic circuit assembly testing device 1 is provided with an adapter 51 having a conductive member 52 with a deformable and flexible structure, bearing the connection to the assembly 21, and capable of testing test object pins 24b in the opened state and testing the test object pins 24b in the short-circuited state while they are fitted to the conductive member 52. A short-circuit failure of the test object pins 24b is detected at the test in the opened state, and an open-circuit failure is detected at the test in the short-circuited state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention incorporates a multi-chip module (hereinafter referred to as an MCM), a built-in means for controlling and observing the voltage of a signal pin, and an LSI or a boundary scan having only one chip. The present invention relates to a test apparatus for an electronic circuit assembly such as a printed circuit board (PCB), a test method using the means, and an adapter for connecting a test machine used for the test and the electronic circuit assembly.

In particular, the present invention relates to an open / short fault of an external input / output pin of an electronic circuit assembly and an internal interconnection test performed by using the means. The present invention also relates to a test apparatus for an electronic circuit assembly when the means is a boundary scan circuit, a test method using the means, and an adapter for connecting a test machine used for the test and the electronic circuit assembly. In particular, the present invention relates to a connection test of an electronic circuit assembly using a standard external test mode (EXTEST function) in a boundary scan system.

In a manufacturing process of an electronic circuit assembly such as an MCM on which an LSI chip is mounted, an LSI
It is difficult to repair the substrate on which the SI chip is mounted in a post-assembly process, and this also causes an increase in product cost. Therefore, only the parts which are determined to be non-defective in the unit test of the LSI chip and the unit test of the board in the pre-assembly process are used in the manufacture of the electronic circuit assembly.

[0004] Therefore, most of the failures remaining after the assembly process are short-circuit (short-circuit) failures and open (open) failures (so-called “short-circuit” failures) mainly caused by solder blitches or unattached solder.
(Floating). Under such circumstances, the post-assembly test mainly targets the interconnection between the LCI chips and the connection between the LSI chip and the external input / output pins of the package constituting the electronic circuit assembly.

[0005]

2. Description of the Related Art The voltage of a conventional signal pin is controlled and controlled.
Testing of an electronic circuit assembly incorporating the means for observing, for example, by supplying power to the means of the electronic circuit assembly, as is well known when the means is a boundary scan circuit (the means being a boundary scan circuit; In such a case, the open fault and the short fault of the electronic circuit assembly are simultaneously detected by the EXTEST function of the circuit.

At this time, in order to check the connection between the external input / output pins of the package and the LSI chip, in addition to the external input / output pins for controlling the test circuit (hereinafter, appropriately referred to as control pins), All the external input / output pins to be tested (hereinafter, appropriately referred to as test target pins) are connected to the pin electronics of the tester. FIG. 13 is a diagram illustrating a conventional boundary scan test method and a conventional tester.

As shown in FIG. 13, a tester using the above-described method for testing an electronic circuit assembly having a built-in means for controlling and observing the voltage of a signal pin, such as a tester using the boundary scan method, is a tester. It has the same number of pin electronics channels as the signal pins to be tested among the external input / output pins of the device under test, which is the electronic circuit assembly to be tested.

Although omitted in FIG. 13 for the sake of convenience, the electronic circuit assembly to be tested usually has hundreds to thousands of signal pins as pins to be tested, so that the pin electronics channel of the tester also has several hundreds. Thousands are needed.

[0009]

When the mounting state of the external input / output pins of the device under test is multi-pin and high-density,
Regarding the connection between the external input / output pins of the device under test and the pin electronics of the test apparatus, there are the following two problems. One is that due to physical constraints, it is difficult to obtain an electrical connection between the external input / output pins of the device under test and the test device simultaneously for all pins to be tested and independently for each pin. That is what. Even if it could be implemented, it would be very expensive to implement the means because of its difficulty.

Therefore, it is a problem to easily establish the above-mentioned electrical connection. Another problem is that the pin electronics of the test equipment need to have many channels corresponding to the number of pins to be tested on the device under test, which makes the test equipment expensive. is there. As a result, the testing process may be one of the factors that increase the cost of the product.

Therefore, it is a problem to be able to configure the test apparatus at low cost. As described above, the present invention reduces the number of independent electrical connections between a device under test, which is an electronic circuit assembly, and a test device and the number of pin electronics channels of the corresponding test device, thereby reducing performance. It is intended to suppress an increase in the price of the test apparatus, that is, to provide a low-cost test apparatus.

[0012]

According to the first aspect of the present invention,
A plurality of external input / output pins including a test target pin to be tested and a test control input / output pin, and independently control the voltage of each test target pin via the test control input / output pin and independently control the voltage. An electronic circuit assembly test method for testing an electronic circuit assembly, comprising: a test means capable of observing an electronic circuit assembly, comprising: connecting the test means control using the test control input / output pin; The test target pin is made open only while maintaining the connection, the short-circuit fault of the test target pin is detected using the test means, and further, the test target pin is formed only of the conductor while maintaining the connection. A short-circuit structure is brought into contact with the structure to short-circuit each other, a test voltage is applied to the pins at a time, and an open failure of the pin to be tested is detected using the means.

According to a second aspect of the present invention, in the electronic circuit assembly testing method according to the first aspect, the test means is a boundary scan circuit built in the electronic circuit assembly. According to a third aspect of the present invention, a plurality of external input / output pins and a voltage of a pin to be tested among the external input / output pins are controlled so that the voltage can be observed, and a control pin among the external input / output pins is used. An electronic circuit assembly test apparatus for testing an electronic circuit assembly, the test means having an operation controlled through the control means, the connection means being connected to the control pin for controlling the test means, and An adapter that can be tested in an open state and that can be tested in a short-circuited state with each other is provided, and a short-circuit failure of the pin to be tested is detected in the test in the open state using the test means. An open failure of the test target pin is detected by a test by applying a test voltage in the short-circuit state.

According to a fourth aspect of the present invention, in the electronic circuit assembly test apparatus according to the third aspect, the test means for controlling the voltage of the pin to be tested and observing the voltage is a boundary scan built in the electronic circuit assembly. It is a circuit. According to a fifth aspect of the present invention, in the electronic circuit assembly test apparatus according to the third or fourth aspect, the adapter has at least one easily deformable and flexible structure for a short-circuiting conductive member. When,
A conductive connection probe for connecting to the control pin for controlling the test means, and a support having a lumen for supporting the conductive member and accommodating the probe, The probe penetrates the conductive member on the support and can be housed in the lumen in the support, and a portion in contact with the conductive member is provided with insulating means to provide a conductive member. A tip that is interrupted by a conductive elastic member in the lumen and protrudes from the lumen to a position higher than the conductive member on the support. The height of the portion is made variable according to pressing from above, and the connection is enabled by contact between the tip and the control pin from above the probe, and the pin to be tested is In the open state by maintaining the conductive member in a state of not contacting Test, and further, the position of the distal end of the probe is lowered by pressing the external input / output pin from above, and the test object is maintained while maintaining the connection by the contact between the distal end of the probe and the control pin. The pin is brought into contact with the short-circuiting conductive member to enable a test in the short-circuit state.

According to a sixth aspect of the present invention, in the electronic circuit assembly test apparatus according to the fifth aspect, when the pin to be tested contacts the conductive member for short-circuit due to the pressing from above, the external input / output is provided. An insulating device is provided in a position corresponding to the pin in the conductive member so that a pin other than the test target pin and the control pin in the pin cannot contact the conductive member.

According to a seventh aspect of the present invention, in the electronic circuit assembly testing apparatus according to the sixth aspect, an insulating device provided at a position corresponding to the pin in the conductive member is provided in the conductive member. It is characterized by being an insulating tube penetrated and provided. According to an eighth aspect of the present invention, in the electronic circuit assembly test apparatus according to any one of the fifth to seventh aspects, the conductive member for short-circuit is a conductive member formed by braiding a metal wire. It is a characteristic cloth.

According to a ninth aspect of the present invention, in the electronic circuit assembly test apparatus according to any one of the fifth to eighth aspects, an insulating means provided at a portion of the probe in contact with the conductive member. Is an insulating film for coating the probe, and the probe is a probe having a portion in contact with the conductive member, which is insulatingly coated.

According to a tenth aspect of the present invention, in the electronic circuit assembly test apparatus according to the third or fourth aspect, the adapter is a conductive member for connecting to the control pin for controlling the test means. A plurality of short-circuit probes that are short-circuited with each other to form the short-circuit state by connection with the test target pin, and a lumen capable of accommodating the connection probe and the short-circuit probe, respectively. The connection probe and the short-circuit probe are respectively held in the lumen, and the connection probe is supported by an elastic body having conductivity, and a tip protruding from the lumen. The part is made variable in height position according to pressing from above, and further,
The tip of the connection probe is set so as to be higher than the tip of the short-circuiting probe in a state where there is no pressing, and the contact between the tip and the control pin from above the connection probe is made. In addition to enabling the connection, the test target pin is maintained in a state of not contacting the short-circuiting probe to enable the test in the open state, and further, by pressing the external input / output pin from above, The position of the distal end of the connection probe is lowered, and the pin to be tested is brought into contact with the short-circuiting probe while the connection by the contact between the distal end of the connection probe and the control pin is maintained. It is characterized in that a test in a state is enabled.

According to the eleventh aspect of the present invention, the voltage of a plurality of external input / output pins and the pin to be tested among the external input / output pins can be controlled to observe the voltage, and the voltage of the external input / output pin can be controlled. A test means operation-controlled via a control pin;
A test adapter for connecting an electronic circuit assembly having an electronic circuit assembly, and an electronic circuit assembly test apparatus for controlling the operation of the test means and detecting a short fault and an open fault of the pin to be tested of the electronic assembly. The connection of the electronic circuit assembly for controlling the means, and the opening of the test target pins of the electronic circuit assembly while maintaining the connection, and the shorting of the pins to each other. Opening the test pin with detection of a short failure of the test pin in the open state using the test means by the test apparatus and collectively applying a test voltage to the test pin in the short state. It is characterized in that failure detection is enabled.

According to a twelfth aspect of the present invention, in the electronic circuit assembly test adapter according to the eleventh aspect, the test means for controlling the voltage of the pin to be tested and observing the voltage includes a boundary built in the electronic circuit assembly. It is a scan circuit. According to a thirteenth aspect of the present invention, in the electronic circuit assembly test adapter according to any one of the eleventh and twelfth aspects, the short-circuit conductive member having at least one easily deformable and flexible structure; A conductive connection probe for connecting to the control pin for controlling a test means, and a support having a lumen for supporting the conductive member and accommodating the probe, the probe comprising: Is penetrable through the conductive member on the support and can be housed in the lumen in the support, and an insulating means is provided at a portion in contact with the conductive member to provide the conductive member. A distal end that is disconnected from the member and is supported by an elastic body having conductivity in the lumen and protrudes from the lumen to a position higher than the conductive member on the support; Changes its height position according to pressure from above The connection is made possible by contact between the tip and the control pin from above the probe, and the test object pin is kept in contact with the short-circuiting conductive member so as to be opened. In this state, the position of the distal end of the probe is lowered by pressing the external input / output pin from above, and the connection by the contact between the distal end of the probe and the control pin is maintained. The test object pin is brought into contact with the short-circuiting conductive member to enable the test in the short-circuit state.

According to a fourteenth aspect of the present invention, in the electronic circuit assembly test adapter according to the thirteenth aspect, when the pin to be tested contacts the conductive member for short-circuit due to the pressing from above, the external input is performed. An insulating device is provided in a position corresponding to the pin in the conductive member so that pins other than the test pin and the control pin among the output pins cannot contact the conductive member.

According to a fifteenth aspect of the present invention, in the electronic circuit assembly test adapter according to the fourteenth aspect, the insulating device provided at a position corresponding to the pin in the conductive member is provided in the conductive member. Characterized in that it is an insulating tube penetrated through. According to a sixteenth aspect of the present invention, in the electronic circuit assembly test adapter according to any one of the thirteenth to fifteenth aspects, the conductive member for short-circuiting is configured by braiding a metal wire. It is a conductive cloth.

According to a seventeenth aspect of the present invention, in the electronic circuit assembly test adapter according to any one of the thirteenth to sixteenth aspects, there is provided an insulating member provided at a portion of the probe in contact with the conductive member. The means is an insulating film for coating the probe, and the probe is a probe having a portion in contact with the conductive member, which is insulatingly coated.

According to an eighteenth aspect of the present invention, in the electronic circuit assembly test adapter according to any one of the eleventh and twelfth aspects, a conductive connection for connecting to the control pin for controlling the test means is provided. Block, a plurality of short-circuit probes that are short-circuited to each other to form the short-circuit state by connection with the test target pin, and a resin block having a lumen capable of accommodating the connection probe and the short-circuit probe, respectively. The connection probe and the short-circuit probe are respectively held in the lumen, and the connection probe is supported by an elastic body having conductivity, and the tip protruding from the lumen is upward. The height of the connection probe is made variable according to the pressure from the probe, and in the absence of the pressure, the distal end of the connection probe is closer than the distal end of the short-circuit probe. And the control pin is brought into contact with the control pin from above the connection probe, and the test pin is not in contact with the short-circuit probe. To allow the test in the open state, and further lowers the position of the distal end of the connection probe by pressing the external input / output pin from above, so that the distal end of the connection probe and the control pin The test object pin is brought into contact with the short-circuiting probe while the connection by the contact is maintained, thereby enabling the test in the short-circuit state.

Here, the principle of detecting a short-circuit failure of an electronic circuit assembly and an open failure of an external input / output pin in the electronic circuit assembly test method and test apparatus according to the present invention will be described. First, the principle of detecting a short-circuit failure of an electronic circuit assembly, particularly a short-circuit failure in a state where a pin to be tested among input / output pins of the electronic circuit assembly is open, will be described with reference to FIG.

The conditions for enabling detection of this short-circuit failure are the following three conditions. Condition 1. Some or all of the LSIs mounted on the electronic circuit assembly have built-in voltage observing means capable of distinguishing at least two different voltage values applied to input / output pins of some or all of the LSIs. And that the observed value can be read through the test circuit.

Condition 2. A part or all of the LSI mounted on the electronic circuit assembly has at least two different voltage values that can be distinguished by the voltage observation means built in the LSI itself, by making the voltage values of some or all of the input / output pins of the LSI. Voltage control means capable of controlling the voltage value through a test circuit. Condition 3. Each wiring (hereinafter referred to as "net" as appropriate) to be subjected to short-circuit failure detection is connected to a pin having at least one voltage observation means and to a pin having at least one voltage control means. Or connected to the pin electronics of the test equipment.

Under the above conditions, when the input / output pins of the electronic circuit assembly are connected to both the pins having the voltage control means and the pins having the voltage observation means of the LSI, the input / output pins to be tested of the assembly are provided. It is possible to detect a short-circuit failure in a state where is opened. (A) of FIG.
(E) shows an ideal case, in which each of the LSIs in the electronic circuit assemblies 200, 210, 220, 230, 240 shown in FIG.
The test pins 202, 212, 222, 232, and 242 of 201, 211, 221, 231, and 241 have both voltage control means and voltage observation means. In such a test object, the electronic circuit assemblies 200, 210, 2
As shown in FIG. 1, not only the internal wiring of 20, 230, 240 but also the wiring connected to the input / output pins 202, 212, 222, 232, 242 are tested.
Without connecting 2,222,232,242 to the test equipment,
The test can be performed while being left open.

Further, as shown in FIGS. 1D and 1E, LS
If the I231, 241 incorporates a resistor (usually referred to as "pull-up", hereinafter referred to as "pull-up") 233, 243 for fixing the open-circuit voltage, the voltage control means Conflicts can be avoided and safer tests can be performed without stressing the device. Accordingly, different voltages (“High” in FIG. 1)
And "Low") between the two wirings shown in FIG.
As shown in the figure, when there is no short-circuit failure, as applied, High is applied when High is applied, and Lo is applied when Low is applied.
w can be read.

However, when a short-circuit fault occurs, for example, when a short-circuit fault 213 occurs between the test target pins 212a and 212b as shown in FIG.
Also, as shown in FIG. 1C, when the short-circuit fault 223 occurs on the wiring connecting the test target pins 222a and 222b and the LSI 221, the read voltage of these wirings becomes the same value, or The voltage difference becomes smaller.

At this time, since a voltage different from the voltage applied to one or both is read, it can be seen that a short failure 223 has occurred between the two wirings. FIG.
In (B) and (C), a high voltage is applied because a low voltage (Low) side acts more strongly than a high voltage (High) side when a voltage control means (eg, driver) competition occurs. Abnormality (Low reading) is detected by the voltage observing means (receiver or comparator) on the side of the side.

As shown in FIGS. 1D and 1E, the LSIs 231 and 241 have a pull-up 23 inside.
3,243, and when the driver is set to a high impedance state (indicated by HiZ in the figure) to form a high voltage state as shown in FIG. Is expected to be read,
In the case where the short failure 234 occurs between the test target pins 232a and 232b as shown in FIG.
As shown in (E), the short-circuit fault 244 is
In the case where it occurs on the wiring connecting the LSIs 241 and 242b and the LSI 241, an abnormality (Low reading) is detected in each case as in FIGS. 1B and 1C.

Thus, the existence of a short-circuit fault is known.
In this test, competition between the voltage control means can be avoided as described above, and a safer test can be executed without applying stress to the device. Next, the principle of detecting an open failure of a test target pin of an electronic circuit assembly will be described with reference to FIG.

The conditions for enabling the detection of the open fault are the following four conditions. Condition 1. Some or all of the LSIs mounted on the electronic circuit assembly have built-in voltage observing means capable of distinguishing at least two different voltage values applied to input / output pins of some or all of the LSIs. And that the observed value can be read through the test circuit.

Condition 2. A part or all of the LSI mounted on the electronic circuit assembly has at least two different voltage values that can be distinguished by the voltage observation means built in the LSI itself, by making the voltage values of some or all of the input / output pins of the LSI. Voltage control means capable of controlling the voltage value through a test circuit. Condition 3. Each wiring (hereinafter, appropriately referred to as "net") to be subjected to the open fault detection is connected to a pin having at least one voltage observation means and connected to a pin having at least one voltage control means. Or be connected to the pin electronics of the test equipment. Then, the signal pins of all the LSIs to be subjected to the open fault detection have voltage observation means and / or voltage control means.

Condition 4. The voltage value of each pin when the input / output pins of the assembly are open must not be undefined. Since this detection test is performed by applying a voltage from outside to the input / output pins of the electronic circuit assembly, which is the device under test, the condition 3 relating to the voltage control means is naturally satisfied. Since the voltage is applied from the outside, the driver connected to the external input / output pin is not necessary as a test condition, but it is desirable that the driver be controlled to a high impedance state if possible (at this time, The element may be damaged depending on the case). However, when the voltage value in the open state is undefined, the driver needs to execute the test in the enabled state.

In the ideal case shown in FIGS. 2A and 2B, the input / output pins 302, 3 of the LSIs 301, 311
Pull-ups 303 and 313 are built in 12a and 312b, and the input / output pins 302 and 31 are provided when the driver is in a high impedance state (indicated by Hiz in the figure).
When the 2a and 312b are in the open state, a high voltage state (indicated by High in the figure) is established.

In this state, as shown in FIG.
When the terminals 2, 312a and 312b are collectively short-circuited to the ground (GND), as shown in FIG. 2A, if there is no open failure, the low voltage (Low) is detected in all the wirings. However, as shown in FIG.
When 14 occurs, a high voltage (High) is read at the input / output pin 312b connected to the net, which indicates the presence of an open fault.

As described above, as long as the principle of detecting a short circuit and an open circuit of the external input / output pin of the electronic circuit assembly in the electronic circuit assembly test method and test apparatus according to the present invention is followed, the external input / output pin to be tested has a short circuit. In any of the detections of the open fault, it is not necessary to individually connect to the pin electronics of the test apparatus, and it can be seen that each pin can be tested by forming the open state and the short state collectively.

Therefore, according to the first, second, third, and fourth aspects of the present invention, there is provided a device under test having means for controlling and observing the voltage of a pin to be tested, such as a boundary scan circuit. In a test of an electronic circuit assembly such as a certain MCM, a step of detecting a short-circuit failure performed by opening a pin to be tested and a step of detecting an open failure performed by short-circuiting a plurality of signal pins are separately performed. It is possible to do.

Accordingly, it is possible to reduce the number of independent electrical connections required between the device for testing the electronic circuit assembly and the device under test. Therefore, the number of pin electronics channels of the test apparatus used for the test can be reduced, and a simple test can be performed. Then, it is possible to suppress an increase in price without lowering the performance of the test device used for the test, that is, to provide a low-cost test device.

According to the fifth, eighth and ninth aspects of the present invention, a short-circuit state of a signal pin to be tested in an electronic circuit assembly such as an MCM to be tested is
The signal pin is deformed and responds to the pressing of the signal pin from the conductive member of the adapter, in particular, because of its own flexibility and ease of deformation, while securing the electrical connection of the pin to be tested. By inserting into a cloth made of a metal wire that can be inserted into itself, it is possible to create evenly and reliably each of the plurality of signal pins.

The probe provided so as to penetrate the cloth made of the metal wire is conductive and its height position is variable. Therefore, it is possible to change the height position corresponding to the vertical movement for inserting the test object pin into the cloth and pulling it out of the cloth, and the movement of the control pin which moves up and down together with the test object pin is possible. It is possible to maintain that contact at all times.

Insulation is ensured by the insulating coating and the like at the side of the probe that does not come into contact with the control pins, and the electrical connection between the probe and the metal wire cloth is completely cut off. ing. Therefore, it is possible to separately execute the step of detecting a short-circuit failure performed by leaving the test target pin of the electronic circuit assembly open and the step of detecting the open failure performed by short-circuiting a plurality of signal pins. Thus, it is possible to reduce the number of independent electrical connections between the test device for testing the electronic circuit assembly and the device under test.

Therefore, it is possible to reduce the number of pin electronics channels of the test apparatus used for the test, to enable a simple test, and to suppress an increase in the price of the test apparatus without lowering the performance. We can provide the test equipment of the price. According to the inventions of claim 6 and claim 7, it is desired to form a signal pin or a short-circuit state in which there is no need to perform a test among signal pins to be tested in an electronic circuit assembly such as an MCM to be tested. For a missing signal pin, it is possible to keep it open during testing, without shorting it alone.

Then, only the other signal pins are short-circuited under a certain condition, and the open fault can be detected in the short-circuit state. Therefore, it is possible to perform a test under detailed conditions according to the characteristics of the test object, and it is possible to perform an accurate test. According to the invention of claim 10, two types of conductive probes having different heights are provided in the adapter, and the higher one is connected to the pin electronics of the test apparatus for connection,
The lower one was short-circuited for short-circuiting, and the height position of at least the higher probe was made variable.

Therefore, when the control pin of the external input / output pins in the electronic circuit assembly such as the MCM to be tested comes into contact with the higher probe, the control pin test apparatus is kept open while the test pin is open. When the external I / O pin is pushed down against the adapter and the position of the higher connection probe is lowered to the lower short-circuit probe, the pin under test contacts the short-circuit probe. It became possible to make it.

At this time, it is possible to independently short-circuit a plurality of pins to be tested while maintaining the connection of the control pins to the test apparatus. Accordingly, a step of detecting a short-circuit failure that is performed by opening the pin to be tested of the electronic circuit assembly, and
It is possible to separately execute the steps of detecting an open fault performed by short-circuiting a plurality of the signal pins,
It is possible to reduce the number of independent electrical connections between the test device for testing the electronic circuit assembly and the device under test.

Accordingly, the number of pin electronics channels of the test apparatus used for the test can be reduced, and a simple test can be performed. In addition, an increase in the price of the test apparatus can be suppressed without lowering the performance. We can provide the test equipment of the price. According to the eleventh and twelfth aspects of the present invention, in a test of an electronic circuit assembly such as an MCM which is a device under test having a means for controlling and observing a voltage of a pin to be tested such as a boundary scan circuit, It is possible to separately execute the step of detecting a short-circuit failure performed by opening the pin to be tested using the apparatus for testing the assembly and the step of detecting the open-circuit failure performed by shorting the signal pins. It becomes possible.

Therefore, it is possible to reduce the number of independent electrical connections required between the device for testing the electronic circuit assembly and the device under test. Therefore, it is possible to reduce the number of channels of the pin electronics of the test apparatus used for the test, enabling a simple electronic circuit assembly test,
An increase in price can be suppressed without lowering the performance of the test apparatus used for the test.

Claims 13, 16 and 17
According to the described invention, a short-circuit state of a signal pin to be tested in an electronic circuit assembly such as an MCM, which is a device under test, is changed to a conductive member having the signal pin, in particular, the flexibility and deformation of its own. It is deformed to respond to the pressing of the pin from ease, and by inserting the pin to be tested into a cloth made of a metal wire that can be inserted inside itself while securing the electrical connection. , For each of the plurality of signal pins.

The probe provided so as to penetrate the cloth made of the metal wire is conductive and its height position is variable. Therefore, it is possible to change the height position corresponding to the vertical movement for inserting the test object pin into the cloth and pulling it out of the cloth, and the movement of the control pin which moves up and down together with the test object pin is possible. It is possible to maintain that contact at all times.

Insulation is ensured by an insulating coating or the like at the side of the probe that does not come in contact with the control pin, and the electrical connection with the metal wire cloth is completely cut off. ing. Therefore, the detection of a short-circuit failure, which is performed by an apparatus for testing an electronic circuit assembly by executing a test pin of the electronic circuit assembly in an open state, and the detection of an open failure, which is performed by short-circuiting a plurality of signal pins, are separately performed. And the number of independent electrical connections between the device that tests the electronic circuit assembly and the device under test can be reduced.

Accordingly, the number of pin electronics channels of the device used for the test can be reduced, a simple test can be performed, and an increase in the price of the test device for the electronic circuit assembly can be suppressed without lowering the performance. According to the invention of claims 14 and 15, among signal pins to be tested in an electronic circuit assembly such as an MCM which is an apparatus under test for testing the electronic circuit assembly,
Signal pins that do not need to be tested or signal pins that do not want to be short-circuited can be left open without being short-circuited during testing by the equipment that tests the electronic circuit assembly. It is.

Then, only the other signal pins are short-circuited under certain conditions, and the device can detect an open fault in the short-circuit state. Therefore, it is possible to perform a test using the test device of the electronic circuit assembly under fine conditions according to the characteristics of the device under test, and to perform an accurate test. According to the invention described in claim 18, two types of conductive probes having different heights are provided, the higher one is connected to the pin electronics of the test apparatus for connection, and the lower one is short-circuited to each other for short-circuit, and further at least. The height of the higher probe was made variable.

Therefore, when the control pin of the external input / output pins in the electronic circuit assembly such as the MCM to be tested comes into contact with the higher probe, the test of the control pin is performed while the test pin is kept open. When the external I / O pin is pushed down against the adapter and the position of the higher connection probe is lowered to the lower short-circuit probe, the pin to be tested is connected to the short-circuit probe. It is now possible to make contact.

At this time, a plurality of pins to be tested can be short-circuited independently while the connection of the control pins to the test apparatus is maintained. Therefore, the detection of a short-circuit failure performed by setting the test target pin of the electronic circuit assembly to the open state and the detection of the open failure performed by short-circuiting a plurality of the signal pins performed by the test apparatus are separately performed. It is possible to reduce the number of independent electrical connections between the device for testing the electronic circuit assembly and the device under test.

Accordingly, the number of pin electronics channels of the test device of the electronic circuit assembly used for the test can be reduced, a simple test can be performed, and an increase in the price of the test device can be suppressed without lowering the performance. .

[0059]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A test method and a test apparatus for an electronic circuit assembly according to the present invention, and a test target performed by the test adapter are an MCM, an LSI on which only one chip is mounted, and a printed circuit board on which a boundary scan is mounted. PC
It is to ensure that all wirings in the electronic circuit assembly such as B) are free from short-circuit faults and open faults.

Therefore, it is very important to detect the short-circuit fault and the open fault of the external input / output pin of the electronic circuit assembly, as well as to detect the short-circuit fault and the open fault in the interconnection inside the electronic circuit assembly. The test of the interconnection inside the electronic circuit assembly can be performed in both the process of detecting the short-circuit fault or the open fault of the external input / output pin,
It is desirable to take in either form during either test.

The detection of a short-circuit fault and an open fault of an external input / output pin of the electronic circuit assembly is performed as follows. The device under test, which is an electronic circuit assembly, does not require any special conditions for the device under test used in this test, but the LSI must satisfy the above three conditions for short fault detection and four conditions for open fault detection. A means for controlling and observing the voltage of a signal pin to be tested such as a boundary scan cell is mounted in an electronic component such as the above. Specifically, an MCM or 1 equipped with such means
An LSI on which only a chip is mounted can be a device under test, and a printed circuit board (PC
B) is also a test object.

A test for detecting a short fault and an open fault is performed on the device under test in the following two test processes. The first test process is a process of detecting a short circuit between LSIs in a device under test, a short circuit between external input / output pins, and a short circuit between a signal terminal of the LSI and an external input / output pin of a package under test. is there.

In this process, the test is performed with all the signal pins of the device under test open. Only necessary test control pins and power supply pins of the device under test are connected to the test equipment. The voltage or logic value of the net under test is controlled by the driver of the LSI itself, and a pattern devised so as to have different values at least once for any two nets is given. In this state, the voltage or logical value of the net under test is read.

If a short-circuit fault occurs between nets that are voltage-controlled to different voltages or logical values, the voltages or logical values of those nets are the same. Alternatively, a voltage or a logical value different from the logical value is read. The read voltage or logical value of the net is compared with the voltage or logical value of the driver of each net.

When a voltage or a logical value different from the voltage or logical value applied to each net is read from the driver, it is diagnosed that a short-circuit fault has occurred in the net. In this process, since no open fault of the external input / output is detected, if the short fault and the open fault occur simultaneously, the short fault may not be found. This fault will be detected as an open fault in the second test process.

The second test process is a process for detecting an open failure of the external input / output pin of the device under test. In this process, the test is performed by shorting all the external input / output pins of the device under test or partially shorting them. The device under test used in the second test process was determined to have no single short-circuit fault by the first test process. If a DUT with a failure found in the first test process is used in the second test process, it may not be possible to correctly detect an open failure or identify the location of the failure, or the device may be damaged. Because there is.

However, continuing the test without repairing the short-circuit fault is certainly dangerous. However, if the fault can be specified by other means and it can be determined that there is no danger, an open fault detection test should be performed. It is possible. A voltage value of a test target net is applied to a group of short-circuited pins through a means for applying a certain test voltage collectively from a test apparatus side and controlling and observing a voltage of a test target signal pin such as a boundary scan circuit on an LSI side. Or observe a logical value. From the test apparatus side, whether to drive the external input / output pin of the device under test to a voltage or a logical value different from when the external input / output pin is opened, or to drive both a high level and a low level voltage or a logical value Is one of

That is, when the test apparatus is driven to a pin group formed by short-circuiting a plurality of pins to be tested to a voltage or a logical value different from that when the external input / output pins of the device under test are opened, If the same voltage or logic value as when the external I / O pin of the DUT is opened among the voltages or logic values of all the nets connected to the group of pins can be read, the DUT connected to the net It is diagnosed that an open failure has occurred in the external I / O pin of

Alternatively, when a group of pins in which a plurality of pins are short-circuited are sequentially driven by a voltage or a logical value of both a high level and a low level from the test apparatus, the voltage or the logical value of all nets connected to the group of the pins is driven. Among them, the voltage or logical value given from the test device is High
If the same voltage or logical value can be read both at the time of and at the time of Low, it is diagnosed that an open fault has occurred in the external input / output pin of the device under test connected to the net.

It should be noted that the detection of the open fault in the connection between the input / output pins of the LSI may belong to either the first test process or the second test process.

[0071]

【Example】

(Embodiment 1) A first embodiment according to the present invention, which relates to an electronic circuit assembly test apparatus for testing a device under test incorporating a boundary scan circuit as a means for controlling and observing the voltage of a signal pin provided therein. This will be described with reference to the drawings.

FIG. 3 is a diagram for explaining a configuration of a main part of an electronic circuit assembly test apparatus according to a first embodiment of the present invention, together with a device under test. An electronic circuit assembly test apparatus 1 according to a first embodiment of the present invention includes an electronic circuit assembly (LSI in FIG. 1) 22 having a boundary scan circuit, and an electronic circuit assembly having a plurality of external input / output pins 24. In the figure, the test of MCM) 21 is performed.

A conductive member 52 having at least one easily deformable and flexible structure is provided to connect with the electronic circuit assembly 21 for controlling the boundary scan circuit, and to control the external input / output of the test object. An adapter 51 is provided which can be tested by leaving the pins 24 in an open state, and by inserting the external input / output pins 24 to be tested into a conductive member 52 to make them short-circuited with each other. I do.

The external input / output pins 2 to be tested of the electronic circuit assembly (MCM) 21 in the test in the open state
4 is characterized by detecting a short-circuit fault and detecting an open fault of the external input / output pin 24 to be tested of the electronic circuit assembly (MCM) 21 in the test in the short-circuit state. Further details below, details of the DUT, details of the adapter,
And a specific test method using them will be described.

First, the test object used in this example will be described. FIG. 4 is a front view of an MCM which is a device under test of the electronic circuit assembly test apparatus of the present embodiment. As shown in FIGS. 3 and 4, the test object used for the test of the electronic circuit assembly test apparatus 1 according to the embodiment of the present invention is as follows.
LSI 22 as an electronic component having a boundary scan circuit
Are mounted on the substrate 23, and a plurality of external input / output pins 2
4 is an MCM (multi-chip module) 21 which is an electronic circuit assembly including

The MCM 21 used at this time is the solder ball 2
5 is mounted between the substrate 23 and the LSI 22 by flip-chip mounting, so that it is not possible to inspect unattached solder or solder bridges by appearance inspection. And this MC
All signal pins of the three LSIs mounted on the M21 have a built-in bidirectional boundary scan cell. All signal nets on the MCM 21 are pulled up (pull-up). When the signal pins 24 are opened in the power-on state and all the drivers of the LSI 21 are set to high impedance (HiZ), all signal nets are High. Designed to be level.

In FIG. 3, TDI, TMS, TCK, T
DO, GND, VDD: TDI: test data input pin; TMS: L by electronic circuit assembly test equipment
Pins for SI mode setting, TCK for TMS and TDI
TDO transfer synchronization (clock) signal pin
Represents a pin for outputting test data, GND represents a ground pin, and VDD represents a power supply pin, and these are control pins 24a which must be connected to control a test circuit by boundary scan.

In FIG. 3, 6 is sandwiched between these six pins.
The unconnected pins of the book become the pins 24b to be tested. Next, the adapters 51 and 71 provided in the electronic circuit assembly test apparatus of the present embodiment will be described. FIG. 5 is a sectional view showing a configuration of a main part of an adapter used in the electronic circuit assembly test apparatus of this embodiment. FIG. 5A shows an example of an adapter used in the electronic circuit assembly test apparatus of this embodiment. Show. FIG. 5B shows another example of the adapter used in the electronic circuit assembly test apparatus of the present embodiment.

The adapters 51 and 71 of the electronic circuit assembly test apparatus of the present embodiment include conductive members 52 and 72
And resin blocks 54 and 74 supporting the conductive members 52 and 72, and insulating plates 55 and 75 provided to cover the conductive members 52 and 72 with the resin blocks 54 and 74 interposed therebetween. Wiring patterns 64 and 84 are formed on a part of the front surface, and these wiring patterns 64 and 84 are sandwiched between the back surfaces of the resin blocks 54 and 74 that support the conductive members 52 and 72, respectively. 7
4, printed boards 65 and 85, resin blocks 54 and 74, insulating plates 55 and 75, and conductive members 5
2, 72 and the printed board 65, 85 are insulated probe sockets 56, 76 whose tips are fixed to the printed boards 65, 85 with solders 66, 86, and are housed inside the probe sockets 56, 76. Conductive probe 6
2,82.

The conductive members 52 and 72 are the same, and a metal wire is looped on conductor plates 53 and 73 that are grounded and connected to ground (GND) via the electronic circuit assembly test apparatus 1. It is a cloth-like member configured to be knitted into a shape. Therefore, it has a very flexible structural characteristic and can change its own shape in response to an external pressure. Specifically, during the test of the MCM 21 by the boundary scan, the external input / output pins 24 of the MCM 21 are allowed to be inserted and can be inserted.

The resin blocks 54 and 74 have M
When the CM 21 is inserted into the adapters 51 and 71 during the test, the resin block 5 is placed at a position corresponding to the position of the test control pin 24 a among the external input / output pins 24 of the MCM 21.
Lumens 57, 77 penetrating through 4, 74 are provided.
Further, at the positions corresponding to the positions of the external input / output pins 24 where the test is not performed, the inner cavities 58 and 78 that penetrate the similar resin blocks 54 and 74 are provided.

Further, at the position facing the upper opening of the bores 57, 58, 77, 78 penetrating the resin blocks 54, 74, the bores 59, 75 also penetrating the insulating plates 55, 75.
60, 79, and 80 are provided. Further, the insulating plate 5
In addition to the lumens 57, 58, 77, and 78, the external input / output pins 24b for testing when the MCM 21 is inserted into the adapters 51 and 71 at the time of the test are provided in the conductive member. It has lumens 61 and 81 for insertion.

The adapters 51 and 71 connect the conductive probes 62 and 82 housed in the insulating probe sockets 56 and 76 to the inner surfaces 59 of the insulating plates 55 and 75 via the probe sockets 56 and 76. , 79 and the lumens 57 and 77 of the resin blocks 54 and 74, and penetrate the conductive members 52 and 72. Therefore, the connection for controlling the boundary scan circuit by the adapters 51 and 71 is made by contact between the control pins 24a of the external input / output pins corresponding to the boundary scan circuit of the MCM 21 and the probes 62 and 82.

At this time, the probes 62 and 82 change the shape of the surface of the distal end that comes into contact with the distal end of the external input / output pin 24a.
In order to prevent the external input / output pin 24a from being displaced or dislodged, the external input / output pin 24a has a shape depressed inward, specifically, a shape whose vertical cross section forms a V-shape.
The probes 62 and 82 are accommodated in probe sockets 56 and 76 while being supported by a conductive elastic body. Therefore, the tips of the probes 62 and 82 partially project from the openings of the tips of the probe sockets 56 and 76 due to the support.

This elastic body is a metal spring.
It is desirable in view of its strength and reliability. In this embodiment, the metal springs 63 and 83 are used. Spring 6
The probes 62, 82 are supported by the probes 3 and 83, and the positions of the tips thereof are moved to the probe socket 5 according to the externally applied pressure.
Probe socket 5
6, 76 can be moved up and down.

Therefore, at this time, the pressure is applied to the external input / output pin 2
4a, the force of the springs 63, 83 repelling the pressure applied to the tips of the probes 62, 82,
The connection by contact between the tips of the probes 62 and 82 and the tips of the external input / output pins 24a is strong. Also, printed boards 65 of springs 63 and 83 supporting the probes 62 and 82,
The tip on the 85 side protrudes outside the probe sockets 56 and 76 from the lower tip that penetrates the printed boards 65 and 85 of the probe sockets 56 and 76,
The penetrating tip of 76 is in contact with the solders 66, 86 fixing to the printed boards 65, 85.

The solders 66 and 86 are printed boards 65 and 8
5 are also in contact with the wiring patterns 64 and 84 connected to the pin electronics 2 of the electronic circuit assembly test device 1 on the electronic circuit assembly test device 5. As a result, the springs 63 and 83 and the pin electronics 2 are electrically connected. Therefore, probe 6
The MCMs 21 and 82 are electrically connected to the pin electronics 2 via the metal springs 63 and 83, and are connected to the probes 62 and 82 by contact.
Input / output pin 2 corresponding to the boundary scan circuit
4a and the electronic circuit assembly test apparatus 1 are electrically connected.

At this time, the insulating probe socket 5
6 and 76, the independence of the electrical connection to the conductive members 52 and 72 through which the probes 62 and 82 pass is reliably ensured. In addition, the adapter 51 is inserted through the conductive member 52 by passing the insulating insulating tube 67 through the lumen 60 of the insulating plate 55 and the lumen 58 of the resin block 54. Unnecessary portions of the external input / output pins are inserted into the insulating tube 67, and the unnecessary external input / output pins and the conductive member 5 are tested.
2 can be electrically disconnected.

In the adapter 71, instead of the insulating insulating tube 67, a probe socket 76 that does not house the probe 82 is used, and the lumen 80 of the insulating plate 75 and the lumen of the resin block 74 are used. It penetrates the conductive member 72 through 78 and is inserted. At this time, the probe socket 76 is not fixed to the printed board 85 by soldering, but has its tip penetrated similarly to the case where the probe 82 is housed inside.

Therefore, in the short-circuit state, a part of the external input / output pins that do not need to be tested are inserted into the insulated probe socket 76 and the electrical connection between the external input / output pins that do not need to be tested and the conductive member 72 is made. Connection can be interrupted. 5A and 5B show the adapters 51 and 71, respectively.
In both cases, two probes 62 and 82 housed in the probe sockets 56 and 76 and the
7 or one probe socket 76 that does not house a probe
Book and one of the insulating plates 5
5,75 lumens 61,81 are depicted and shown.

However, each of the adapters 51 and 71 is an example of the adapter in the embodiment according to the present invention, and the probes 62 and 82 and the bores 61 and 8 for inserting pins are used.
The number and arrangement of 1 and the like can be arbitrarily selected according to the structure of the device under test such as the MCM to be tested, and the adapter can be configured. Next, a specific test method using the test object and the adapter will be described.

FIG. 6 is a diagram for explaining the state of the DUT MCM and the adapter before the start of the test by the boundary scan and during the test. FIG. 6A shows the state before the test.
FIG. 6B shows a state during the test in the first test process, and FIG. 6C shows a state during the test in the second test process. FIG. 7 is a diagram illustrating the principle of the test in the first test process on the device under test MCM of the test apparatus of the present embodiment performed by the boundary scan.

FIG. 8 is a view for explaining the principle of the test in the second test process on the device under test MCM of the test apparatus of the present embodiment performed by the boundary scan. FIG. 6A is a view showing a state in which the MCM 21 is placed on the probe 62 and is not pressurized before the start of the test. MCM21
The tip of the external input / output pin 24a is not in contact with the probe 62. Before the start of the test, the MCM 21 is set on the adapter 51 in this state.

FIG. 6B shows a state of the adapter 51 including the MCM 21 and the probe 62 in the first test process. In the first test process, the MCM 21 is pressurized and lowered to an intermediate position determined by a stopper (not shown) having a mechanism for applying the MCM 21 from above. This intermediate position is
The connection between the external input / output pins 24a and the probe 62 is sufficiently performed by the action of the spring 63 inside the probe socket 56, but none of the external input / output pins 24b is in a position where the external input / output pins 24b are not in contact with the conductive member 52. It is arbitrarily determined according to the condition of the test object.

At this time, as shown in FIG. 7, only the necessary minimum power supply pins and ground pins 24a are connected to the test apparatus 1, and the external input / output pins 24b to be tested are all conductive members 52. Are all open without being connected. In this state, a power supply pin required to drive the electronic circuit assembly test circuit of the LSI 22 and a JTAG (Joint)
Test Action Group pin (TDI,
TMS, TCK, TDO) 24a are electrically connected to the test apparatus 1 and provide a pattern devised so that at least one of two arbitrary nets has a mutually different value. .

When the logical value of the net of interest is read, if there is a short portion 31 as shown in FIG. 7, a strong logical value is read instead of a weak logical value at the corresponding pin,
A short fault is recognized. If there is no short-circuit portion and a weak logical value is read, it is diagnosed that there is no short-circuit failure.

In this first test, a test for an open failure between the pins of the LSI is performed at the same time. FIG. 6C shows a state of the adapter 51 including the MCM 21 and the probe 62 in the second test process. Next, in the second test process, as shown in the figure, the MCM 21 is further pressurized to be lowered with respect to the adapter 51, and the probe 62 is set at a position determined by a stopper (not shown) having a contact mechanism. Is done.

The connection of the power supply pin and the JTAG pin 24a to the test apparatus 1 is maintained by the action of the probe 62, and the insertion into the conductive member 52 causes all the signal pins 24b to be tested to be connected as shown in FIG. To ground (GND). Then, the signal pin 24b 'to be tested, which is not subjected to the test, is inserted into the insulating tube 67 as shown in FIG.

At this time, scan-in is performed so that all drivers connected to the signal pin 24b to be tested have high impedance (HiZ), and the logical values of all the signal pins 24b to be tested are read. External input / output pin 24b
All the nets leading to G
Because there is no open failure because it is connected to ND,
The logics of these nets are all at the low level. Since the signal pin 24 of the LSI 22 of the device under test 21 has a built-in pull-up resistor, the external input / output pin 24b ″
If there is an open fault 32 shown in FIG. 8 between the LSI and the LSI 22, the net connected to the pin 24b ″ is High.
Level is observed.

A high level is set at the pins of the LSI 22 belonging to the net connected to the external input / output pins 24b of the MCM 21.
If the level is read, it is diagnosed that the net has an open fault. Next, a description will be given of performing a test using another example of the adapter using the probe socket 76 instead of the insulating tube 67 shown in FIG. 5B used in the electronic circuit assembly test apparatus according to the present invention. I do.

FIG. 9 is a diagram for explaining the state of another example of the test object MCM and the adapter before the start of the test using the boundary scan and during the test. FIG. 9A shows the state before the test. FIG. 9B shows a state during the test in the first test process, and FIG. 9C shows a state during the test in the second test process. FIG. 9A is a diagram showing a state in which the MCM 21 is placed on the probe 82 and is not pressurized before the test is started. The tip of the external input / output pin 24a of the MCM 21 is not in contact with the probe 82. Before starting the test, the MCM 21 is set on the adapter 71 in this state.

FIG. 9B shows the state of the adapter 71 including the MCM 21 and the probe 82 in the first test process. As in the test using the adapter shown in FIG. 6, the presence or absence of a short-circuit fault is diagnosed in the MCM in the first test process. In this first test, LSI
The test for the open failure between the pins is also performed at the same time.

FIG. 9C shows a state of the adapter 71 including the MCM 21 and the probe 82 in the second test process. As in the test using the adapter shown in FIG. 6, the presence or absence of the open fault in the MCM is diagnosed in the second test process. As described above, the short circuit and open circuit failure occurring in the external input / output pins of the electronic circuit assembly having the means for controlling / observing the voltage of the external input / output pins provided in the boundary scan circuit and the like are extremely small in the electronic circuit assembly test apparatus. It can be implemented using a pin electronics channel.

(Embodiment 2) An electronic circuit assembly according to a second embodiment of the present invention, in which a device under test incorporating a boundary scan circuit as a means for controlling and observing the voltage of a signal pin is provided. The test apparatus will be described with reference to the drawings. FIG. 10 is a diagram illustrating a configuration of a main part of an electronic circuit assembly test apparatus according to a second embodiment of the present invention, together with a device under test.

An electronic circuit assembly test apparatus 101 according to a second embodiment of the present invention comprises a plurality of external input / output pins 1.
24 and the pin 124 to be tested among the external input / output pins 124
an electronic component (LSI in the figure) 122 having a boundary scan circuit as a test means capable of controlling the voltage of b and observing the voltage and having its operation controlled via a control pin 124a in the external input / output pin 124; Are tested with an electronic circuit assembly (MCM in the figure) 121 having the above.

The test pins 124b are connected to the control pins 124a for controlling the boundary scan circuit, and the test pins 124b are opened and tested. A possible adapter 151 is provided. The test target pins 12 of the electronic circuit assembly (MCM in the figure) 121 are used in the test in the open state by using the boundary scan circuit.
4b is detected, and an open failure of the test target pin 124b is detected in a test by applying a test voltage in the short state.

With respect to the device under test used in this embodiment, the electronic circuit assembly (MCM) 21 (FIG. 4) which is the device under test in the electronic circuit assembly test apparatus 1 of the first embodiment.
The same one was used. Hereinafter, the details of the adapter 151 and a specific test method using the adapter 151 will be described.

First, the adapter 151 provided in the electronic circuit assembly test apparatus 101 of this embodiment will be described. FIG. 11 is a sectional view showing a configuration of a main part of an adapter used in the electronic circuit assembly test apparatus of the present embodiment.
The adapter 151 of the electronic circuit assembly test apparatus 101 of this embodiment includes a resin block 154 and the test apparatus 1.
A printed circuit board 165 having a wiring pattern 164 connected to the pin electronics 102 of No. 01 formed partially on the surface and provided with the wiring pattern 164 sandwiched between the wiring block 164 and the back surface of the resin block 154; 165 penetrates from the upper surface of the resin block 154 and is fixed to the printed board 165 by solder 166, and the insulating probe socket 156 which is an inner cavity of the resin block 154 is housed in the probe socket 156. And a conductive connection probe 152 for connecting to a control pin 124a for controlling the boundary scan circuit, and a pin 1 to be tested.
A plurality of short-circuit probes 1 short-circuited with each other by the net 155 forming the short-circuit state by connection with the short-circuit probes 24b.
53.

The probe 152 for connection and the control pin 1
The method and configuration of the connection with 24a and the short circuit of the plurality of shorting probes 153 by the net will be described in more detail later. Then, the connection probe 152
The shorting probe 153 is supported by conductive elastic members 163 and 171 in the probe socket 156, respectively, and the tips 152a and 153 project from the opening of the probe socket 156 on the surface of the resin block 154.
The height position of “a” can be changed up and down in accordance with pressing from above.

The elastic body is preferably a metal spring.
It is desirable in view of its strength and reliability. In this embodiment, metal springs 163 and 171 are used. Further, the tip 152a of the connection probe is set to be higher than the tip 153a of the short-circuiting probe in a state where there is no pressing. Therefore, the connection probe 152
The contact between the tip 152a and the control pin 124a from above allows the connection and enables the pin 124 to be tested.
b is kept out of contact with the short-circuiting probe 153 to enable the test in the open state.

At this time, the contact between the tip 152a and the control pin 124a can be made strong by pressing the control pin 124b from above the connection probe 152, and the contact position is provided on the connection probe 152. It is determined by the action of a stopper (not shown) of the assigned contact mechanism. Further, the distal end 15 of the connection probe 152 is pressed by pressing the external input / output pin 124 from above.
2a is lowered, and the tip 152 of the connection probe is lowered.
The test target pin 124b is connected to the short-circuit probe 153 while maintaining the connection by contact between the control pin 124a and the control pin 124a.
The test in the short-circuit state is enabled by contacting the tip portion 153a of the short-circuit.

At this time, when the pin 124b to be tested is pressed from above the short-circuiting probe 153, the tip 15
Strong contact between the control pin 2a and the control pin 124a is possible, and the contact position is determined by the action of a stopper (not shown) having a contact mechanism provided on the connection probe 152 and the short-circuit probe 153. You. The probes 152 and 153 are connected to the external input / output pins 124.
The shape of the surface of the tip portions 152a and 153a that are in contact with the tip portions of the inside is formed so as to be depressed inward so as to prevent the external input / output pin 124 from being displaced and coming off. The shape is as follows.

The tip on the printed board 165 side below the spring 163 for supporting the connection probe 152 comes out of the probe socket 156 from the lower tip of the probe socket 156 penetrating the printed board 165, and the probe The penetrating tip of the socket 156 is connected to the printed board 165.
Is in contact with the solder 166 that is fixed to the solder. This solder 16
Reference numeral 6 also contacts a wiring pattern 164 connected to the pin electronics of the electronic circuit assembly test apparatus 101 on the printed board 165, and as a result, the spring 163 and the pin electronics 102 are electrically connected.

Therefore, the probe 152 is a metal spring 1
The pin electronics 102 is electrically connected to the electronic circuit assembly test apparatus 101 through the 63 by connecting the control pin 124 a of the boundary scan circuit of the MCM 121 to be in contact with the probe 152. become. The tip of the printed board 165 below the spring 171 supporting the short-circuiting probe 153 is connected to the printed board 16 of the probe socket 156.
5 penetrates through the lower end of the probe socket 156 and comes into contact with the solder 172 fixing the penetrating end of the probe socket 156 to the printed board 165.

This solder 172 is also in contact with the net 155 provided in the printed board 165, and as a result, the spring 1
71 and the net 155 are electrically connected.
Therefore, all of the plurality of short-circuit probes 153 are electrically connected to the net 155 via the metal spring 171, and the MCM test pin 124 b is brought into contact with the short-circuit probe 153. As a result, the short-circuit state described above is formed.

In FIG. 11, the adapter 151
Two short-circuit probes 153 housed in the probe socket 156 and two connection probes 152 are drawn on both sides thereof. However, the adapter 151 is an example of an adapter provided in the test apparatus according to the second embodiment of the present invention. The number and arrangement of the probes 152 and 153 are different from those of the test object such as the MCM to be tested. The adapter can be arbitrarily selected according to the structure, and can be configured together with the other components.

Next, a specific test method using the MCM 121 to be tested and the adapter 151 will be described. FIG. 12 is a diagram for explaining the state of the DUT MCM and the adapter before the start of the test by the boundary scan and during the test. FIG. 12A shows the state before the test.
FIG. 12B shows a state during the test in the first test process, and FIG. 12C shows a state during the test in the second test process.

FIG. 12A shows the MCM12 before the start of the test.
FIG. 2 is a view showing a state in which the device No. 1 is placed on a connection probe 152 and is not pressed. Before the start of the test, the MCM 121 is set on the adapter 151 in this state. FIG. 12B shows the MCM 121 and the connection probe 15 in the first test process.
2 shows the state of the adapter 51 including the number 2.

In the first test step, the MCM 121 is pressurized and lowered to an intermediate position determined by a stopper (not shown) having a mechanism for applying the MCM 121 from above. In this intermediate position, the connection between the control pin 124a and the connection probe 152 is sufficiently made, but none of the test target pins 124b is in contact with the short-circuit probe 153. Therefore, only the control pin 124a is connected to the pin electronics 102 of the test apparatus 101, and all the external input / output pins 124b to be tested are in an open state.

In this open state, the above-described test can be performed in the same manner as in the first embodiment, and the short-circuit failure of the interconnection inside the MCM 121 and the input / output pin 124b can be detected. Next, in the second test process, as shown in FIG.
The probe 152 is set at a position determined by a stopper (not shown) having a mechanism for lowering and contacting the probe 152.

The connection of the control pin 124a to the test apparatus 101 is maintained by the action of the probe 152. When the control pin 124a comes into contact with the short-circuiting probe 153, all the signal pins 124b to be tested are connected to the ground (GND) as shown in FIG. ). In this short-circuit state, the above-described test is performed in the same manner as in the first embodiment, and the interconnection inside the MCM 121, the wiring between the input / output pins 124b and the substrate of the MCM 121, the wiring on the substrate, the wiring on the substrate and the LSI 12
2 can be detected for each open fault.

As described above, a short circuit fault and an open fault occurring at an external input / output pin of an electronic circuit assembly having a means for controlling / observing a voltage of an external input / output pin provided in a boundary scan circuit or the like can be measured by an electronic circuit assembly test apparatus. It can be implemented with very few pin electronics channels.

[0123]

According to the first, second, third, and fourth aspects of the present invention, the number of pin electronics channels of the test apparatus used for the test can be reduced, and a simple test can be performed. And Then, it is possible to suppress an increase in price without lowering the performance of the test device used for the test, that is, to provide a low-cost test device.

According to the fifth, eighth and ninth aspects of the present invention, it is possible to reduce the number of independent electrical connections between a test apparatus for testing an electronic circuit assembly and a device under test. Becomes Therefore, it is possible to reduce the number of pin electronics channels of the test apparatus used for the test, to enable a simple test, and to suppress an increase in the price of the test apparatus without deteriorating the performance, that is, a low-cost test. Equipment can be provided.

According to the sixth and seventh aspects of the present invention, it is possible to perform a test under detailed conditions according to the characteristics of the device under test, and to perform an accurate test. According to the tenth aspect of the present invention, it is possible to reduce the number of independent electrical connections between the test device for testing the electronic circuit assembly and the device under test. Therefore, it is possible to reduce the number of pin electronics channels of the test apparatus used for the test, to enable a simple test, and to suppress an increase in the price of the test apparatus without deteriorating the performance, that is, a low-cost test. Equipment can be provided.

According to the eleventh and twelfth aspects of the present invention, it is possible to reduce the number of independent electrical connections required between a device for testing an electronic circuit assembly and a device under test. Therefore, it is possible to reduce the number of pin electronics channels of the test apparatus used for the test, to enable a simple electronic circuit assembly test, and to suppress a rise in price without lowering the performance of the test apparatus used for the test. Can be.

(13), (16) and (17)
According to the described invention, it is possible to reduce the number of independent electrical connections between a device for testing an electronic circuit assembly and a device under test. Therefore, the number of pin electronics channels of the device used for the test can be reduced, a simple test can be performed, and an increase in the price of the test device for the electronic circuit assembly can be suppressed without lowering the performance.

According to the fourteenth and fifteenth aspects of the present invention, an electronic circuit assembly can be tested by a test apparatus under fine conditions according to the characteristics of a device under test, and an accurate test can be performed. . According to the eighteenth aspect, it is possible to reduce the number of independent electrical connections between the device for testing the electronic circuit assembly and the device under test.

Accordingly, the number of pin electronics channels of the test device of the electronic circuit assembly used for the test can be reduced, a simple test can be performed, and an increase in the price of the test device can be suppressed without lowering the performance. .

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the principle of detecting a short-circuit failure when a test target pin of an electronic circuit assembly is open.

FIG. 2 is a diagram illustrating the principle of detecting an open failure of a pin to be tested in an electronic circuit assembly.

FIG. 3 is a diagram illustrating a configuration of a main part of an electronic circuit assembly test apparatus according to a first embodiment of the present invention, together with a device under test.

FIG. 4 is a front view of an MCM which is a device under test of the electronic circuit assembly test apparatus of the present embodiment.

FIG. 5 is a cross-sectional view showing a main configuration of an adapter used in the electronic circuit assembly test apparatus according to the first embodiment of the present invention.

FIG. 6 is a diagram illustrating states of the MCM and the adapter before and during a test by a boundary scan using the electronic circuit assembly test apparatus of the first embodiment and during the test.

FIG. 7 is a diagram illustrating the principle of a test performed in a first test process on the MCM of the test apparatus according to the first embodiment performed by the boundary scan.

FIG. 8 is a diagram illustrating a principle of a test in a second test process on the device under test MCM of the test apparatus according to the first embodiment performed by the boundary scan.

FIG. 9 is a diagram illustrating another example of the state of the MCM and the adapter before and during the test by the boundary scan using the electronic circuit assembly test apparatus of the first embodiment.

FIG. 10 is a diagram illustrating a configuration of a main part of an electronic circuit assembly test apparatus according to a second embodiment of the present invention, together with a device under test.

FIG. 11 is a cross-sectional view showing a main configuration of an adapter used in an electronic circuit assembly test apparatus according to a second embodiment of the present invention.

FIG. 12 is a diagram for explaining states of an MCM and an adapter before and during a test by a boundary scan using the electronic circuit assembly test apparatus of the second embodiment.

FIG. 13 is a diagram illustrating a conventional boundary scan test method and test apparatus.

[Explanation of symbols]

1,101 Electronic circuit assembly test apparatus 2,102 Pin electronics 21,121 MCM 22,122,201, 211,221,231,24
1,301,311 LSI 23 board 24,124 external input / output pin 24a, 124a control pin 24b, 124b signal pin 24b ′ signal pin not tested 25 solder ball 51,71,151 adapter 52,72 Conductive members 53, 73 Conductor plates 54, 74, 154 Resin blocks 55, 75 Insulating plates 56, 76, 156 Probe sockets 57, 58, 59, 60, 61, 77, 78, 79, 8
0, 81 Lumen 62, 82 Probe 63, 83, 163, 171 Spring 64, 84, 164 Wiring pattern 65, 85, 165 Printed circuit board 66, 86, 166, 172 Solder 67 Insulation tube 152 Connection probe 153 Short-circuit probe 155 net 200, 210, 220, 230, 240, 300, 3
10 Electronic circuit assembly 202, 212a, 212b, 222a, 222b, 2
32a, 232b, 242a, 242b Open pin 302, 312a, 312b Input / output pin 213, 223, 234, 244 Short fault 233, 243 pull-up 314 Open fault

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Koji Uesaka 4-1-1, Kamidadanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Hidenori Imazato 4-1-1 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture No. 1 Fujitsu Co., Ltd. (72) Inventor Shuichi Kameyama 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture 1-1 Inside Fujitsu Co., Ltd. No. 1 Inside Fujitsu Limited (72) Inventor Takeshi Yanase 4-1-1 Kamikadanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited

Claims (18)

[Claims] A plurality of external input / output pins each comprising a test target pin to be tested and a test control input / output pin, and independently controlling the voltage of each test target pin via the test control input / output pin. An electronic circuit assembly test method for testing an electronic circuit assembly, comprising: a test means capable of independently observing the voltage, wherein the test means control connection is performed using the test control input / output pin. Opening the pin under test while maintaining the connection, detecting a short-circuit failure of the pin under test using the test means, and further connecting the pin under test while maintaining the connection. A short-circuited structure composed of only the short-circuited structure and a short-circuited state, applying a test voltage to the pins collectively, and detecting an open failure of the test target pin using the means. Electronic circuit assembly testing method. 2. The electronic circuit assembly test method according to claim 1, wherein said test means is a boundary scan circuit built in said electronic circuit assembly. 3. A plurality of external input / output pins and a voltage of a pin to be tested among the external input / output pins are controlled so that the voltages can be observed and operated via control pins among the external input / output pins. An electronic circuit assembly test apparatus for testing an electronic circuit assembly, comprising: a test means to be controlled, the electronic circuit assembly test apparatus having a control pin for controlling the test means, and each of the test target pins being in an open state. An adapter capable of performing a test in a short-circuited state with each other, and using the test means, detecting a short-circuit failure of the pin to be tested in the test in the open state, An electronic circuit assembly test apparatus, wherein an open failure of a test target pin is detected by a test by applying a test voltage in a short-circuit state. 4. The electronic circuit assembly test apparatus according to claim 3, wherein the test means for controlling the voltage of the pin to be tested and observing the voltage is a boundary scan circuit built in the electronic circuit assembly. Electronic circuit assembly test equipment. 5. The electronic circuit assembly test apparatus according to claim 3, wherein the adapter includes at least one short-circuit conductive member having an easily deformable and flexible structure; A probe for conductive connection for connection with the control pin for controlling a test means, and a support having a lumen for supporting the conductive member and accommodating the probe, the probe comprising: Is penetrable through the conductive member on the support and can be housed in the lumen in the support, and an insulating means is provided at a portion in contact with the conductive member to provide the conductive member. A distal end that is disconnected from the member and is supported by an elastic body having conductivity in the lumen and protrudes from the lumen to a position higher than the conductive member on the support; Can change its height position in response to pressure from above. The connection is made possible by contacting the tip and the control pin from above the probe, and the test object pin is maintained in a state in which it does not contact the short-circuiting conductive member, and the open state is maintained. In addition, the position of the distal end of the probe is lowered by pressing the external input / output pin from above, and the connection is maintained while maintaining the contact between the distal end of the probe and the control pin. An electronic circuit assembly test device, wherein a test pin is brought into contact with the short-circuiting conductive member to enable a test in the short-circuit state. 6. The electronic circuit assembly test apparatus according to claim 5, wherein the pin to be tested in the external input / output pins is contacted when the pin to be tested and the conductive member for short-circuit contact with each other by the pressing from above. An electronic circuit assembly test apparatus, wherein an insulating device is provided in a position corresponding to the pin in the conductive member so that a pin other than the control pin cannot contact the conductive member. 7. The electronic circuit assembly test apparatus according to claim 6, wherein the insulating device provided at a position corresponding to the pin in the conductive member is provided so as to penetrate into the conductive member. An electronic circuit assembly test device, which is an insulating tube. 8. The electronic circuit assembly test apparatus according to claim 5, wherein the short-circuiting conductive member is formed by knitting a metal wire. An electronic circuit assembly test apparatus, characterized in that: 9. The electronic circuit assembly test apparatus according to claim 5, wherein an insulating means provided on a portion of the probe in contact with the conductive member coats the probe. An electronic circuit assembly test apparatus, comprising: an insulating film, wherein the probe is a probe having a portion in contact with the conductive member and coated with an insulating material. 10. The electronic circuit assembly test apparatus according to claim 3, wherein the adapter is a conductive connection probe for connecting to the control pin for controlling the test means. A plurality of short-circuiting probes that are short-circuited with each other to form the short-circuit state by connection with the test target pin, and a resin block having a lumen capable of accommodating the connection probe and the short-circuiting probe, respectively. The connection probe and the short-circuiting probe are respectively held in the lumen, and the connection probe is supported by a conductive elastic body, and a tip protruding from the lumen is pressed from above. The height position is made variable according to
Further, in the absence of the pressing, the distal end of the connection probe is set to be higher than the distal end of the short-circuiting probe, and the distal end and the control pin from above the connection probe are connected to each other. In addition, the connection is enabled by the contact of the pin, and the test target pin is kept in a state of not contacting the short-circuiting probe to enable the test in the open state. The position of the tip of the connection probe is lowered by pressing, and the test pin is brought into contact with the short-circuiting probe while maintaining the connection by the contact between the tip of the connection probe and the control pin. An electronic circuit assembly test apparatus, wherein a test in the short-circuit state is enabled. 11. A method of controlling voltages of a plurality of external input / output pins and a pin to be tested among the external input / output pins so as to observe the voltages and operate via control pins among the external input / output pins. An electronic circuit assembly having a controlled test means, and an electronic circuit assembly test apparatus for controlling the operation of the test means and detecting a short-circuit failure and an open failure of the test target pin of the electronic assembly. The test adapter to connect the electronic circuit assembly for controlling the means, and to open the test target pins of the electronic circuit assembly while maintaining the connection; and Short-circuit detection of the pin to be tested in the open state using the test means by the test apparatus and the short-circuit state. The tested pins electronic circuit assembly test adapter, characterized in that to allow the open failure detection with collective application of the test voltage to the test subject pin in. 12. The electronic circuit assembly test adapter according to claim 11, wherein the test means for controlling the voltage of the test target pin and observing the voltage is a boundary scan circuit built in the electronic circuit assembly. Characteristic electronic circuit assembly test adapter. 13. The electronic circuit assembly test adapter according to claim 11, wherein at least one conductive member for short-circuiting having a flexible structure that is easily deformable and flexible; A conductive connection probe for connection with the control pin for control, and a support having a lumen for supporting the conductive member and accommodating the probe, wherein the probe is The conductive member on the body can be penetrated and housed in the lumen in the support, and a portion in contact with the conductive member is provided with insulating means to allow the conductive member to communicate with the conductive member. The connection is cut off, and furthermore, the distal end is supported by an elastic body having conductivity in the lumen, and projects from the lumen to a position higher than the conductive member on the support from above. The height position can be changed according to the pressing of The connection between the probe and the control pin is enabled by contacting the control pin with the tip from above the probe, and the pin to be tested is maintained in a state in which the pin does not contact the short-circuiting conductive member. In addition, the position of the tip of the probe is lowered by pressing the external input / output pin from above, and the test is performed while maintaining the connection by the contact between the tip of the probe and the control pin. An electronic circuit assembly test adapter, wherein a target pin is brought into contact with the short-circuiting conductive member to enable a test in the short-circuit state. 14. The electronic circuit assembly test adapter according to claim 13, wherein at the time of contact between the test target pin and the short-circuit conductive member due to the pressing from above, the test target in the external input / output pin is provided. An electronic circuit assembly test adapter, wherein an insulating device is provided in a position corresponding to the pin in the conductive member so that a pin other than the pin and the control pin cannot contact the conductive member. 15. The electronic circuit assembly test adapter according to claim 14, wherein the insulating device provided at a position corresponding to the pin in the conductive member is provided so as to penetrate through the conductive member. An adapter for testing an electronic circuit assembly, wherein the adapter is an insulating tube. 16. The electronic circuit assembly test adapter according to claim 13, wherein the short-circuiting conductive member is formed by braiding a metal wire. An adapter for testing an electronic circuit assembly, which is a cloth. 17. The electronic circuit assembly test adapter according to claim 13, wherein an insulating means provided at a portion of the probe in contact with the conductive member coats the probe. An electronic circuit assembly test adapter, wherein the probe is a probe having a portion in contact with the conductive member coated with an insulating material. 18. The electronic circuit assembly test adapter according to claim 11, wherein a conductive connection probe for connecting to the control pin for controlling the test means; and A plurality of short-circuit probes that are short-circuited with each other to form the short-circuit state by connection with the test target pin, and a resin block having a lumen capable of accommodating the connection probe and the short-circuit probe, respectively. The probe and the short-circuiting probe are each held in the lumen, and the connection probe is supported by a conductive elastic body, and the tip protruding from the lumen has its height increased by pressing from above. The position is variable,
Further, in the absence of the pressing, the distal end of the connection probe is set to be higher than the distal end of the short-circuiting probe, and the distal end and the control pin from above the connection probe are connected to each other. In addition, the connection is enabled by the contact of the pin, and the test target pin is kept in a state of not contacting the short-circuiting probe to enable the test in the open state. Pressing lowers the position of the distal end of the connection probe, and contacts the test pin with the short-circuiting probe while maintaining the connection by the contact between the distal end of the connection probe and the control pin. An electronic circuit assembly test adapter characterized in that a test can be performed in a short state.