JP2005069970A - Ic tester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-speed IC tester while suppressing wiring between printed circuit boards. <P>SOLUTION: The present invention provides an improved IC tester for testing an object to be tested outputting a multistage voltages from a plurality of pins. This IC tester has a plurality of the first printed circuit boards provided in every plurality of the pin lines of the object to be tested, and for converting the multistage voltages of the object to be tested into digital data to conduct computation, and the second printed circuit board for inputting a computation result in the first printed circuit board to conduct computation for all the pins. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an IC tester for testing an object to be tested that outputs a multi-stage voltage from a plurality of pins, for example, a liquid crystal drive driver, etc., and relates to an IC tester that achieves high speed while suppressing wiring between printed circuit boards. .

  The liquid crystal drive driver outputs a multi-stage (multi-gradation) voltage from a plurality of pins to drive the liquid crystal display. An IC tester for testing such a liquid crystal drive driver is described in, for example, Japanese Patent Application Laid-Open No. H10-228707. This will be described below with reference to FIG.

JP 2002-98738 A

  In FIG. 3, an object to be tested (hereinafter abbreviated as DUT) 1 is, for example, a liquid crystal drive driver, which outputs a multistage voltage from a plurality of pins. The switch 2 selects the pin of DUT1. The A / D converter 3 receives the output from the switch 2 and converts it into digital data. The memory 4 stores the digital data from the A / D converter 3. A digital signal processing unit (hereinafter abbreviated as DSP) 5 performs pass / fail judgment of the DUT 1 based on the digital data in the memory 4.

  The operation of such an apparatus will be described below. The DUT 1 outputs a multistage voltage. Then, the switch 2 sequentially selects and outputs the pins of the DUT 1. The A / D converter 3 converts this output into digital data and stores it in the memory 4. Then, the DSP 5 performs arithmetic processing on the magnitude of the absolute value of the output voltage of each pin, the magnitude of variation in the output voltage between the pins, the maximum value, the minimum value, the sum, and the like based on the digital data in the memory 4, and the DUT 1 The quality of the product is judged.

  However, according to such a conventional configuration, when the output voltage of each pin of DUT 1 is measured, the output voltage of each pin of DUT 1 is switched by switch 2 and input to A / D converter 3. Measurement time is required.

  As a method for shortening the time required for such measurement, as shown in FIG. 1 of Patent Document 1, an A / D converter 3 is provided for each pin of the DUT 1, and the output voltage of each pin of the DUT 1 is taken in parallel. A method of calculating with two calculation units is also conceivable. However, the number of pins of a liquid crystal drive driver in recent years has increased to 800 pins, and it takes a long time to calculate if one arithmetic unit is used.

  In addition, the IC tester has a plurality of printed circuit boards mounted in the test head, and one printed circuit board corresponds to, for example, 48 pins of DUT 1 and performs a test, but the data of 800 pins is wired between the printed circuit boards, When calculation is performed by one calculation unit, there is a problem that wiring is difficult.

  SUMMARY OF THE INVENTION An object of the present invention is to realize an IC tester that increases the speed while suppressing wiring between printed circuit boards.

In order to achieve such a problem, the invention according to claim 1 of the present invention is:
In an IC tester that tests a device under test that outputs multi-stage voltages from multiple pins,
A plurality of first printed circuit boards that are provided for each of a plurality of pin systems to be tested, convert the multi-stage voltage of the test target into digital data, and perform calculations;
It has a second printed circuit board for inputting the calculation result of the first printed circuit board and performing operations for all pins.

The invention according to claim 2 is the invention according to claim 1,
The first printed circuit board is
An A / D converter which is provided for each pin system to be tested and converts to digital data;
A first arithmetic circuit that performs an operation on the digital data of the A / D converter,
The second printed circuit board is
The IC tester according to claim 1, further comprising: a second arithmetic circuit that performs an operation on all pins based on a calculation result from the first arithmetic circuit.

The invention according to claim 3 is the invention according to claim 2,
The first printed circuit board is
A differential voltage generator that outputs a differential voltage between the multi-stage voltage of the test object and the expected value voltage;
And a voltage amplifier that amplifies the difference voltage of the difference voltage generator and outputs the amplified voltage to the A / D converter.

The invention according to claim 4 is the invention according to claim 1,
The first printed circuit board is
A switching section for switching a multi-pin system to be tested;
An A / D converter for converting the output of the switching unit into digital data;
A first arithmetic circuit that performs an operation on the digital data of the A / D converter,
The second printed circuit board is
And a second arithmetic circuit that performs an operation on all pins from the arithmetic result of the first arithmetic circuit.

The invention according to claim 5 is the invention according to any one of claims 1 to 4,
The test head includes a first printed board and a second printed board.

  According to the present invention, the plurality of first printed circuit boards convert the output into digital data for each of the plurality of pin groups to be tested, perform an operation, and the operation result results in the second printed circuit board for all pins. Since the calculation is performed, it is possible to increase the speed while suppressing wiring between printed circuit boards.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. Here, the same components as those in FIG.

  In FIG. 1, the test head TH is electrically connected to the DUT 1. The test head TH has a plurality of, for example, 28 pin electronics cards 6 and a printed circuit board 7 mounted thereon. The pin electronics card 6 is a first printed circuit board and is provided for each of a plurality of pin systems of the DUT 1, and converts the multistage voltage of the DUT 1 into digital data and performs an operation. The pin electronics card 6 includes a plurality of, for example, 48 A / D converters 61, an arithmetic circuit 62, a memory 63, and the like. The A / D converter 61 is provided for each pin system of the DUT 1 and converts it into digital data. The arithmetic circuit 62 calculates the maximum value, minimum value, sum, etc. from the digital data of the A / D converter 61 and stores the calculation results (measurement data (digital data), maximum value, minimum value, sum, etc.) in the memory 63. To do. The printed circuit board 7 includes an arithmetic circuit 71 and a memory 72, and inputs the calculation results of the 28 pin electronics cards 6, and performs calculations such as maximum values, minimum values, and sums for all pins. The arithmetic circuit 71 receives the calculation results such as the maximum value, the minimum value, and the total sum from the pin electronics card 6, calculates the overall maximum value, minimum value, the total sum, and the like, and also measures the measurement data (digital data) from the pin electronics card 6. Is stored in the memory 72.

  The operation of such an apparatus will be described below. The DUT 1 outputs a multistage voltage to the pin electronics card 6. Then, the A / D converter 61 of the pin electronics card 6 converts the output of each pin of the DUT 1 into digital data and outputs it to the arithmetic circuit 62. The arithmetic circuit 62 performs arithmetic processing on the correction of the measurement error of the digital data, the maximum value, the minimum value, the sum, and the like and stores them in the memory 63. Then, the arithmetic circuit 62 sends the calculation results such as the measurement data (digital data), the maximum value, the minimum value, and the total sum of the memory 63 to the printed circuit board 7. The arithmetic circuit 71 of the printed circuit board 7 stores the measurement data in the memory 72, calculates the maximum value, the minimum value, the sum, and the like for all the pins from the calculation result and stores them in the memory 72. Whether the DUT 1 is good or bad is determined by a calculation circuit of the main body (not shown) based on the calculation results such as the maximum value, minimum value, and sum stored in the memory 72. Such an operation is repeated for each test item.

  As described above, the plurality of piene electronics cards 6 convert the output into digital data for each of the plurality of pin series of the DUT 1 and perform an operation, and the printed circuit board 7 performs the operation for all the pins according to the operation result. The speed can be increased while suppressing the wiring between them.

  Next, another configuration of the pin electronics card 6 will be described with reference to FIG. Here, the same components as those shown in FIG.

  In FIG. 2, the D / A converter 64 outputs an expected value voltage corresponding to the multi-stage voltage of the DUT 1. The difference voltage generator 65 is provided for each pin of the DUT 1 and outputs a difference voltage between the multi-stage voltage of the DUT 1 and the expected value voltage of the D / A converter 64. A voltage amplifier (hereinafter abbreviated as “PGA”) 66 amplifies the difference voltage of the difference voltage generator 64 with a variable gain, and outputs the amplified voltage to the A / D converter 61.

  The operation of such an apparatus will be described. The DUT 1 outputs a multistage voltage to the pin electronics card 6, and the D / A converter 64 of the pin electronics card 6 outputs an expected value voltage. The difference voltage generator 65 outputs a difference voltage between the output of the DUT 1 and the output of the D / A converter 64. This difference voltage is input via the PGA 66, and the A / D converter 61 converts it into digital data and outputs it to the arithmetic circuit 62. In the same manner as in the apparatus shown in FIG. 1, the arithmetic circuit 62 performs arithmetic processing on the correction of the measurement error of the digital data, the maximum value, the minimum value, the sum, and the like and stores them in the memory 63. Then, the arithmetic circuit 62 sends the calculation results such as the measurement data (digital data), the maximum value, the minimum value, and the total sum of the memory 63 to the printed circuit board 7. The arithmetic circuit 71 of the printed circuit board 7 stores the measurement data in the memory 72, calculates the maximum value, the minimum value, the sum, and the like for all the pins from the calculation result and stores them in the memory 72. Whether the DUT 1 is good or bad is determined by a calculation circuit of the main body (not shown) based on the calculation results such as the maximum value, minimum value, and sum stored in the memory 72. Such an operation is repeated for each test item.

  The present invention is not limited to this, and a configuration in which one A / D converter 61 is provided in the pin electronics card 6 and a switching unit for switching the 48 pins of the DUT 1 is provided and given to one A / D converter 61 is provided. It may be.

  In addition, although the configuration in which the memory 63 is provided and the arithmetic circuit 62 sends the data to the printed circuit board 7 after temporary storage is shown, the memory 63 may be eliminated and the arithmetic circuit 62 may output the result directly to the printed circuit board 7 after the calculation.

It is the block diagram which showed one Example of this invention. It is the figure which showed the other structure of the pin electronics card. It is the figure which showed the structure of the conventional IC tester.

Explanation of symbols

1 DUT
6-pin electronics card 61 A / D converter 62 arithmetic circuit 65 differential voltage generator 66 voltage amplifier 7 printed circuit board 71 arithmetic circuit TH test head

Claims (5)

In an IC tester that tests a device under test that outputs multi-stage voltages from multiple pins,
A plurality of first printed circuit boards that are provided for each of a plurality of pin systems to be tested, convert the multi-stage voltage of the test target into digital data, and perform calculations;
An IC tester comprising: a second printed circuit board for inputting the operation result of the first printed circuit board and performing operations for all pins. The first printed circuit board is
An A / D converter which is provided for each pin system to be tested and converts to digital data;
A first arithmetic circuit that performs an operation on the digital data of the A / D converter,
The second printed circuit board is
2. The IC tester according to claim 1, further comprising: a second arithmetic circuit that performs an operation on all pins based on an arithmetic result of the first arithmetic circuit. The first printed circuit board is
A differential voltage generator that outputs a differential voltage between the multi-stage voltage of the test object and the expected value voltage;
3. The IC tester according to claim 2, further comprising a voltage amplifier that amplifies the difference voltage of the difference voltage generator and outputs the amplified voltage to the A / D converter. The first printed circuit board is
A switching section for switching a multi-pin system to be tested;
An A / D converter for converting the output of the switching unit into digital data;
A first arithmetic circuit that performs an operation on the digital data of the A / D converter,
The second printed circuit board is
2. The IC tester according to claim 1, further comprising: a second arithmetic circuit that performs an operation on all pins based on an arithmetic result of the first arithmetic circuit. The IC tester according to claim 1, wherein the test head includes a first printed board and a second printed board.

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