JPH0795087B2 - Semiconductor integrated circuit measuring device - Google Patents

Description

The present invention relates to a semiconductor integrated circuit measuring device, and more particularly to a general-purpose semiconductor integrated circuit measuring device for logically testing a digital LSI.

[Conventional technology]

Conventionally, this type of semiconductor integrated circuit measuring device has a multi-pin general-purpose VL.
There are SI function testers etc., but this multi-pin general-purpose
The VLSI function tester has functions to test the logic operation of digital LSIs, and to measure the power supply current of the LSI under test and the input threshold voltage of each terminal, input leakage, output voltage, output current, etc. However, when testing an analog / digital mixed LSI that has an analog circuit, it has sufficient performance for testing the digital section, but the analog section is tested with an AC signal for measuring the frequency response. It is inferior in terms of functions such as generation and measurement, or in the resolution of voltage / current measurement.

Conventionally, in order to measure such an analog / digital mixed LSI, there is no choice but to measure the digital part and the analog part in two times by using different testers or by using the analog / digital combined tester. It was

As shown in FIG. 4, a conventional semiconductor integrated circuit measuring device is provided with a load board 42 between a board (hereinafter referred to as a DUT board) 43 on which an LSI to be measured is mounted and a test head 41 of the measuring device. However, this load board 42 only has a role of bridging the signal line between the test head 41 and the DUT board 43, and it is an N-pin compatible tester with m-pins under test.
Was measured, Nm test pins were left unused.

[Problems to be solved by the invention]

Among the above-mentioned conventional measuring methods, the method of separately measuring the analog part and the digital part by two separate testers requires a long measurement time and a large measurement cost.
On the other hand, although the analog / digital dual-purpose tester has a short measuring time and measuring cost, it is not always easy to introduce it because the price per unit is high. Moreover, the number of pins that can be supported is smaller than that of a general-purpose VLSI function tester, and there were still many problems in terms of versatility.

A multi-pin general-purpose VLSI function tester is equipped with a device called a pin electronics card for all the test pins that can support it.Each test pin has a driver for input terminals, a comparator for output terminals, and a driver for input / output terminals. It has versatility so that both comparators can be set. Therefore, if the number of test pins required by the LSI to be measured is smaller than the number of pins that can be supported, the remaining test pins are left unused.

[Means for solving problems]

The semiconductor integrated circuit measuring device of the present invention comprises a second board for connecting the first board and the test pin on the test head between the first board on which the device under test is mounted and the test head of the measuring device. In the LSI measuring apparatus having the board, the board connecting connector is provided on the second board.

Further, in the semiconductor integrated circuit measuring device of the present invention, the test pins on the test head which are not connected to the first board and the first board are connected to each terminal of the board connecting connector. The test pin is connected to a signal line branched from each test pin.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. Referring to FIG. 1, an embodiment of the present invention is a multi-pin general purpose VLSI function tester which utilizes unused test pins to efficiently and accurately test the analog portion of an analog / digital mixed LSI. Area 1 is a test head part in the VLSI function tester, area 2 is a board to which the board connecting connector 6 is attached, which is usually called a load board, and area 3 is a board on which the LSI to be measured is mounted, that is, a DUT board. Part of. The signal line 4 is a line connecting the test head 1 and the DUT board 3 and is provided on the load board 2, and the LSI to be measured 5 is mounted on the DUT board.

The load board 2 selects test pins that are rarely used in consideration of their versatility and uses them for the connector 6 for connecting the board.
Wire to. In addition, the connector 6 has a test head portion 2
The signal lines branched from all the signal lines connected to the DUT board 3 are also routed. Using the load board thus manufactured, various external circuits can be measured by manufacturing an external circuit according to the function of the analog section to be measured and inserting it into the connector 6.

FIG. 2 shows an application example in one embodiment of the present invention. Second
In the figure, the device to be measured is an analog / digital mixed LSI with a built-in 8-bit D / A converter, and for the test of the 8-bit D / A that is the analog part, a circuit surrounded by each number 7 is made on an external board. , Connector 6 on load board 2
Insert it (not shown in the figure). D / A for this circuit
This is well known as a converter testing method, and the linearity error is measured by taking the difference between the outputs of the D / A converter 8 to be measured and the reference D / A converter 9. In this case, the unused test pin can be used as a driver to perform ZERO adjustment and FULL adjustment during measurement. In addition, in the case of this measurement method, if the test pin to which the output of the subtraction circuit is connected is used as a comparator and the high-side and low-side limits are appropriately determined, the linearity error can be checked while running the test pattern. It is possible.

FIG. 3 shows another application example of the embodiment of the present invention. In FIG. 3, the device under test is an analog / digital mixed LSI with a built-in comparator, and the circuit enclosed by the dotted line 71 is used to test the analog part of the comparator.
Is manufactured on an external substrate and fitted into the connector 6 (not shown in the figure). In the case of this circuit, a simple voltage dividing circuit can detect an offset voltage higher than the resolution of the driver.

Thus, the embodiment of the present invention is a mixed analog / digital system.
The LSI can be measured efficiently and accurately without compromising its versatility by using a multi-pin general-purpose VLSI function tester.

〔The invention's effect〕

As described above, according to the present invention, in a multi-pin general-purpose VLSI function tester, the unused test pins and the external board are connected by partially changing the signal line path from the test head to the DUT board, and the analog board -The analog part of the digital mixed LSI can be tested efficiently and accurately, and various types of analog and digital mixed LSI can be tested by changing only the external board. Further, since the present invention uses the existing general-purpose VLSI function tester, the assets can be used as they are and the inspection and selection of the analog built-in digital LSI can be performed with the minimum capital investment.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, FIGS. 2 and 3 are diagrams showing an application example in the embodiment of the present invention, and FIG.
The figure is a diagram showing each board portion used in the conventional measuring apparatus. 1 ... Test head part, 2 ... Road board part, 3 ...
DUT board, 4 ... Signal line, 5 ... LSI to be measured, 6 ...
Board connector, 7,71 ... External board, 8 ... 8bit
D / A converter, 9 …… Standard D / A converter, 10 …… OP
Amplifier, 11 …… resistor, 12 …… comparator, 13 …… 8bit
LSI with built-in D / A converter, 14 ... LSI with built-in comparator.

Claims (1)

[Claims] 1. A first board on which a device to be measured is mounted and a test head of a measuring apparatus, the first board and a second board for connecting a test pin on the test head. In the LSI measuring apparatus, a board connection connector is provided on the second board, and the board connection connector has test pins on the test head that are not connected to the first board. The semiconductor integrated circuit measuring device is characterized in that a test pin connected to the first board is connected to a signal line which is branched by one pin.