JP2000321322A - Method and apparatus for analyzing dc characteristic of integrated circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the working load for an operator. SOLUTION: This apparatus comprises: a sampling time control part 24 for determining the logarithm of an initial set value of a strobe value in the measurement of DC characteristic, the logarithm of a final set value of the strobe value, and the logarithm of the sampling resolution; a sampling time memory 26 for storing the result of the operation by the sampling time control part 24; and a strobe value calculating part 34 providing an initial value of the strobe value in the test of the DC characteristic, with the logarithm of the initial set value of the strobe value, and outputting the value to an IC test part 32 every test until the value of the logarithm of the final set value of the strobe value is obtained by increasing the initial value of the strobe value in accompany with the increase of the number of times of the test with a width of the logarithm of the sampling resolution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC characteristic of an integrated circuit which measures a DC characteristic of an integrated circuit which is a sample to be measured for each strobe value which is a measurement point on a time axis, and displays and analyzes the measurement result. More particularly, the present invention relates to a method and an apparatus for analyzing a DC characteristic of an integrated circuit which displays a measurement result while updating a strobe value.

[0002]

2. Description of the Related Art Conventionally, DC characteristics of an integrated circuit, which is a sample to be measured, are measured based on whether or not a measured value falls within an allowable range of a predetermined voltage value or current value with respect to an arbitrary strobe value. Then, pass / fail in the DC characteristic test of the integrated circuit is determined. Therefore, in order to calculate the optimal strobe value, a range of the strobe value is set, and the range is set according to the number of samplings.
A plurality of tests were performed to find an optimal strobe value.

[0003]

In this conventional DC characteristic analyzing apparatus for an integrated circuit, the range of the strobe value, which is a measurement point on the time axis for measuring the DC characteristic of the integrated circuit, is determined by equally dividing it by the number of samplings. Therefore, the strobe value can be decomposed only in millisecond (ms) or nanosecond (ns) time units, and to determine the optimal strobe value time unit, perform a DC characteristic test for each time unit However, the determination must be made based on each test result, which takes a long time for the analysis, and there is a problem that an operator has a large work load. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method and an apparatus for analyzing a DC characteristic of an integrated circuit, which reduce the work load on an operator.

[0004]

In order to achieve the above object, according to the present invention, a DC characteristic of an integrated circuit which is a sample to be measured is measured for each strobe value which is a measurement point on a time axis. A DC characteristic analysis method of an integrated circuit for displaying and analyzing the measurement result, wherein a logarithm of an initial set value of the strobe value in the DC characteristic measurement is obtained from the data indicating the range of the strobe value and the sampling number of the measurement value of the DC characteristic. Calculate the logarithm of the final set value of the strobe value, and the logarithm of the sampling resolution, and perform the DC characteristic test based on the logarithm of the initial set value of the strobe value, the logarithm of the final set value of the strobe value, and the logarithm of the sampling resolution. The initial value of the strobe value is given as a logarithm of the initial setting value of the strobe value, and the initial value of the strobe value is increased with an increase in the number of DC characteristic tests. Characterized in that the value is increased by the logarithm of the width of the sampling resolution per each test updates until the logarithmic value of the last set value of the strobe value.

According to the first aspect of the present invention, an integrated circuit which measures a DC characteristic of an integrated circuit which is a sample to be measured for each strobe value which is a measurement point on a time axis, and displays and analyzes the measurement result In the DC characteristic analysis method, from the data indicating the range of the strobe value and the sampling number of the measurement value of the DC characteristic, the logarithm of the initial setting value of the strobe value in the DC characteristic measurement, the logarithm of the final setting value of the strobe value, and The logarithm of the sampling resolution is obtained, and the logarithm of the initial setting value of the strobe value, the logarithm of the final setting value of the strobe value, and the logarithm of the sampling resolution are used to determine the initial value of the strobe value at the time of the DC characteristic test. Given as a logarithm of the set value, the initial value of the strobe value is set to the sampling resolution for each test as the number of DC characteristic tests increases. Since the logarithm is increased by the logarithm and updated until the logarithm of the final set value of the strobe value is reached, the DC characteristics of the integrated circuit strobe value can be measured in units of time, and the operator can collectively measure the strobe value. Work load is reduced.

According to a second aspect of the present invention, there is provided an integrated circuit test section for measuring a DC characteristic of an integrated circuit as a sample to be measured for each strobe value as a measurement point on a time axis,
In the integrated circuit DC characteristic analyzer for displaying and analyzing the measurement result of the integrated circuit test unit on a display device, a strobe in the DC characteristic measurement is obtained based on the data indicating the range of the strobe value and the sampling number of the measured value of the DC characteristic. First calculating means for calculating the logarithm of the initial set value of the value, the logarithm of the final set value of the strobe value, and the logarithm of the sampling resolution; storage means for storing the calculation result of the first calculation means; The initial value of the strobe value at the time of the DC characteristic test based on the stored contents is given by the logarithm of the initial setting value of the strobe value, and the initial value of the strobe value increases with the logarithmic width of the sampling resolution as the number of tests increases. And a second calculating means for outputting to the integrated circuit test unit for each test until the logarithm value of the final set value of the strobe value is obtained. The features.

According to a third aspect of the present invention, there is provided the integrated circuit DC characteristic measuring and analyzing apparatus according to the second aspect, further comprising a DC characteristic test measurement value and whether the measurement value is within an allowable range. And a display means for displaying the determination data indicating

According to the second and third aspects of the present invention, the logarithm of the initial setting value of the strobe value and the strobe value in the DC characteristic measurement are obtained from the data indicating the range of the strobe value and the sampling number of the measured value of the DC characteristic. First calculating means for obtaining the logarithm of the final set value and the logarithm of the sampling resolution, a storing means for storing the calculation result of the first calculating means, and a DC characteristic test based on the storage contents of the storing means. The initial value of the strobe value is given by the logarithm of the initial set value of the strobe value, and the logarithm of the final set value of the strobe value is increased by increasing the initial value of the strobe value with the logarithmic width of the sampling resolution as the number of tests increases. And a second calculating means for outputting to the integrated circuit test section for each test until the value of the strobe value becomes the time unit of the strobe value of the integrated circuit. DC characteristic measuring the can be performed collectively, the operator of the working load is reduced.

[0009]

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a configuration of an integrated circuit DC characteristic analyzer according to an embodiment of the present invention. The integrated circuit DC characteristics analyzer according to the embodiment of the present invention measures the DC characteristics of the integrated circuit, which is the sample to be measured, for each strobe value, which is a measurement point on the time axis, and displays and analyzes the measurement results. In the method of analyzing DC characteristics of an integrated circuit, the logarithm of the initial setting value of the strobe value and the final setting value of the strobe value in the DC characteristic measurement are obtained from the data indicating the range of the strobe value and the sampling number of the measurement value of the DC characteristic. Logarithm, and the logarithm of the sampling resolution, the logarithm of the initial setting value of the strobe value, the logarithm of the final setting value of the strobe value, and the initial value of the strobe value at the time of the DC characteristic test based on the logarithm of the sampling resolution, strobe The initial value of the strobe value is sampled for each test as the number of DC characteristic tests increases. A device for carrying out the direct characterization method characterized by increasing a logarithm of the width of the ring-resolution update to a logarithm of the value of the last set value of the strobe value.

The DC characteristic analyzer includes an input device 10 such as a keyboard, and an integrated circuit test device 30 for performing an integrated circuit test.
An integrated circuit test control device 20 for controlling the operation of the integrated circuit test device 30, and a display device 40 such as a display device
It is composed of The input device 10 includes a DC characteristic measurement condition input unit (hereinafter, referred to as a DC characteristic measurement condition input unit) for inputting measurement conditions for DC characteristic measurement.
Recorded as DC measurement condition input section. ) 12 and a DC characteristic measurement start input unit (hereinafter, referred to as a DC measurement start input unit) 14. In addition, the integrated circuit test control device 20 has a DC
A DC characteristic measurement condition memory (referred to as a DC measurement condition memory) 22 for storing DC characteristic measurement measurement condition data input from the measurement condition input unit 12; a sampling time control unit 24; a sampling time memory 26; A characteristic measurement display control unit (DC measurement display control unit) 27 and a DC characteristic measurement result memory (D
C measurement result memory) 28. Here, the sampling time control unit 24 corresponds to the first calculating means of the present invention, and the sampling time memory 26 corresponds to the storing means of the present invention.
Each corresponds.

The integrated circuit test apparatus 30 includes an integrated circuit test section 32 for checking the DC characteristics of the integrated circuit, a strobe value calculation section 34, and a DC characteristic measurement limit memory (hereinafter referred to as a DC measurement limit memory). 36. The display device 40 includes a DC characteristic measurement result display section (hereinafter, referred to as a DC measurement result display section) 42 for displaying a measurement result of the DC characteristic measurement, and a DC characteristic measurement determination limit display section (hereinafter, DC measurement determination limit). (Referred to as a display unit) 44. The strobe value calculation unit 3
Reference numeral 4 corresponds to a second calculating means of the present invention.

FIG. 2 shows the contents stored in the DC measurement condition memory 22. In FIG. 2, the DC measurement condition memory 22
Are a memory area 22A storing a minimum strobe value which is a minimum value of a strobe value, and a memory area 22A storing a maximum strobe value which is a maximum value of a strobe value.
B and a memory area 22C in which the number of samples is stored.
Consists of

FIG. 3 shows the contents stored in the sampling time memory 26. In FIG. 3, a sampling time memory 26 has a memory area 26A in which the logarithm of an initial set value of a strobe value (referred to as a sampling start time) in DC characteristic measurement is stored, and a final set value of a strobe value (referred to as a sampling end time). ) Is stored, and a memory area 26C is stored which stores the logarithm of the sampling resolution.

Next, the operation of the DC characteristic analyzing apparatus according to the embodiment of the present invention shown in FIG. 1 will be described with reference to the flowcharts of FIGS. First, in FIG.
When the operator operates the DC measurement condition input unit 12 to input the minimum strobe value and the maximum strobe value in the measurement of the DC characteristics of the integrated circuit as the sample to be measured, the memory areas 22A and 22B of the DC measurement condition memory 22 are respectively stored. , The minimum strobe value and the maximum strobe value are recorded. Next, the operator operates the DC measurement condition input unit 12 to input the number of measurement points in the range from the minimum strobe value to the maximum strobe value, that is, the number of samplings, into the DC measurement condition memory 22. The sampling number is recorded in the memory area 22C (step 100).

Further, when the DC measurement start input unit 14 is operated to output a start command to the sampling time control unit 24 (step 102), the sampling time control unit 24 reads the DC measurement condition memory 22 from the DC measurement condition memory 22 as shown in the flowchart of FIG. The minimum value of the strobe, the maximum value of the strobe, and the number of samples are read out, and the logarithm of the sampling start time, the logarithm of the sampling end time, and the logarithm of the sampling resolution using these data are calculated and recorded in the sampling time memory 26 (step 104). ). Here, referring to the flowchart of FIG.
The calculation of the logarithm of the sampling start time, the logarithm of the sampling end time, and the logarithm of the sampling resolution will be described.

In FIG. 5, whether the minimum strobe value read from the DC measurement condition memory 22 is smaller than the strobe value of an integrated circuit test device (hereinafter, referred to as an IC test device), that is, whether or not it is smaller than the minimum resolution of the IC test device. Is determined (step 200). If the determination in step 200 is affirmative, the logarithm of the sampling start time is set to lo.
g (the minimum strobe value of the IC test apparatus) is calculated (step 202).

If the determination in step 200 is negative, the logarithm of the sampling start time is calculated as log (minimum strobe value) (step 204). Next, logarithm of sampling end time is log (strobe maximum value)
(Step 206), and the logarithm of the sampling resolution is calculated as (logarithm of sampling end time−logarithm of sampling start time) / (number of samplings−1) (step 208).

Thus, step 10 in FIG.
When the recording of the logarithm of the sampling start time, the logarithm of the sampling end time, and the logarithm of the sampling resolution in the sampling time memory 26 is completed at step 4,
In step 6, the strobe value calculation unit 34 calculates a strobe value using the data recorded in the sampling time memory 26, performs DC characteristic measurement in the IC test unit 32, and records the measurement result in the DC measurement result memory 28. .

Here, the IC test performed in step 106 of FIG. 4 will be described with reference to the flowchart of FIG. In FIG. 6, the number of tests N is set to N in step 300.
= 0 and initialized. Next, the logarithm of the strobe value is calculated as the logarithm of the sampling start time + (the number of tests N × the logarithm of the sampling resolution) (step 302). In step 304, the logarithm of the strobe value obtained in step 302 is compared with the logarithm of the sampling end time, and if the logarithm of the strobe value exceeds the logarithm of the sampling end time, the process is terminated. Step 302
If it is determined that the logarithm of the strobe value does not exceed the logarithm of the sampling end time, the strobe value is calculated as 10 (the logarithm of the strobe value) in step 306, and an IC test is performed in step 308.

Next, at step 310, the strobe value and the measurement result of the IC test are recorded in the DC measurement result memory 28 by the integrated circuit test section (hereinafter, referred to as IC test section) 32. Further, in step 312, the number of tests N is incremented, and the process returns to step 302. The IC test is repeated until the condition is satisfied in step 304, and the results for the number of tests performed are recorded in the DC measurement result memory 28. When the IC test is completed in step 314, the process proceeds to step 108 in FIG.

In step 108, the IC test section 32 outputs an IC test end command to the DC measurement display control section 27. Next, at step 110, the DC measurement display control section 27 displays the DC measurement result on the DC measurement result display section 42. When an IC test is performed, a limit area for judging a pass / fail in a measured value is recorded in the DC measurement judgment limit memory 36 in advance, and information indicating the limit area is displayed in step 112 as a DC measurement judgment limit display. It is displayed on the section 44.

Next, the processing of the sampling time control unit 24 shown in FIG. 5 and the strobe value calculation unit 34 shown in FIG.
A specific example of the processing will be described. First, the DC measurement condition input unit 12 is operated to set the minimum value of the strobe value to 1 m.
s, the maximum value of the strobe value is 10 s, the sampling number is 5, and these data are stored in the DC measurement condition memory 2.
Record in 2. When a start command is output to the sampling time control unit 24 by operating the DC measurement start input unit 14, the sampling time control unit 24
In order to set the reference unit of the minimum strobe value and the maximum strobe value recorded in the measurement condition memory 22 to seconds (s),
The minimum strobe value is 0.001 s.

In FIG. 5, since the minimum strobe value is larger than the minimum strobe value of the IC test apparatus 30 in step 200, the logarithm of the sampling start time is log (0.001), that is, "-3" in step 202. Next, in step 206, the logarithm of the sampling end time is:
Since the maximum value of the strobe is 10 s, log (10),
That is, it becomes "1". Further, in step 208, the logarithm of the sampling resolution is calculated as (1-(−)
3)) / (5-1) is calculated, and the calculation result is “1”.
Becomes

Next, the strobe value calculation unit 34 initializes the number of tests N to 0 in step 300 of FIG. 6, and in the next step 302, the logarithm of the strobe value is -3+ (0 × 1).
And the result is “−3”. Step 3
In step 04, determination is made by comparing the logarithm of the strobe value with the logarithm of the sampling end time. In this example, the logarithm of the strobe value “−3” is smaller than the logarithm of the sampling end time “1”. When the strobe value is calculated, it becomes "0.001 s", that is, 1 ms, as 10-3.

Next, in step 308, a DC characteristic test is performed by the IC test section 32, and in step 310, step 30 is executed.
6 and the measured value of the DC characteristics test performed in step 308 are recorded in the DC measurement result memory 28. Next, at step 312, the number of tests N is incremented, and the process returns to step 302. Step 302
When the processing of steps 312 to 312 is repeated until the determination in step 304 is affirmed, the logarithm of the strobe value becomes −2, −.
1, 0, 1 and the strobe values are 10 ms, 100 m
s, 1s, 10s, and the logarithm of the strobe value is "
2 ". In this way, the results for the number of tests performed are recorded in the DC measurement result memory 28,
The DC measurement display control unit 27 displays the measurement result on the DC measurement result display unit 42.

According to the method of analyzing DC characteristics of an integrated circuit according to the embodiment of the present invention, the DC characteristics of an integrated circuit as a sample to be measured are measured for each strobe value, which is a measurement point on the time axis, and the measurement is performed. In the method of analyzing DC characteristics of an integrated circuit for displaying and analyzing a result, a logarithm of an initial set value of a strobe value in a DC characteristic measurement, a strobe value, based on data indicating the range of the strobe value and a sampling number of a measurement value of the DC characteristic. The logarithm of the final set value of the strobe value and the logarithm of the sampling resolution are determined, and the logarithm of the initial set value of the strobe value, the logarithm of the final set value of the strobe value, and the logarithm of the strobe value at the time of the DC characteristic test based on the logarithm of the sampling resolution. The initial value is given as a logarithm of the initial setting value of the strobe value, and the initial value of the strobe value is increased with an increase in the number of DC characteristic tests. Each test is increased by the logarithmic width of the sampling resolution and updated until the logarithm of the final set value of the strobe value is reached. The work load on the operator can be reduced.

According to the DC characteristic analyzing apparatus for an integrated circuit according to the embodiment of the present invention, the initial setting of the strobe value in the DC characteristic measurement is performed based on the data indicating the range of the strobe value and the sampling number of the measured value of the DC characteristic. Log of the value,
A sampling time control unit 24 for obtaining the logarithm of the final set value of the strobe value and the logarithm of the sampling resolution; a sampling time memory 26 for storing the operation result of the sampling time control unit 24;
The initial value of the strobe value at the time of the DC characteristic test based on the stored contents is given by the logarithm of the initial setting value of the strobe value, and the initial value of the strobe value increases with the logarithmic width of the sampling resolution as the number of tests increases. And a strobe value calculation unit 34 for outputting to the IC test unit 32 for each test until the logarithm of the final set value of the strobe value is obtained. It can be performed collectively, and the work load of the operator is reduced.

[0028]

As described above, according to the first aspect of the present invention, the DC characteristics of the integrated circuit which is the sample to be measured are measured for each strobe value which is a measurement point on the time axis. In the method of analyzing DC characteristics of an integrated circuit for displaying and analyzing a result, a logarithm of an initial set value of a strobe value in a DC characteristic measurement, a strobe value, based on data indicating the range of the strobe value and a sampling number of a measurement value of the DC characteristic. The logarithm of the final set value of the strobe value and the logarithm of the sampling resolution are determined, and the logarithm of the initial set value of the strobe value, the logarithm of the final set value of the strobe value, and the logarithm of the strobe value at the time of the DC characteristic test based on the logarithm of the sampling resolution. The initial value is given as the logarithm of the initial setting value of the strobe value, and the initial value of the strobe value is set for each test with an increase in the number of tests of the DC characteristics. Because the sampling resolution is increased by the logarithmic width of the sampling resolution and updated until the logarithmic value of the final set value of the strobe value is reached, the DC characteristics of the integrated circuit strobe value per time unit must be measured at once. And the burden on the operator is reduced.

According to the second and third aspects of the present invention, the logarithm of the initial setting value of the strobe value in the DC characteristic measurement and the strobe value are obtained from the data indicating the range of the strobe value and the sampling number of the measured value of the DC characteristic. First calculating means for obtaining the logarithm of the final set value and the logarithm of the sampling resolution, a storing means for storing the calculation result of the first calculating means, and a DC characteristic test based on the storage contents of the storing means. The initial value of the strobe value is given by the logarithm of the initial set value of the strobe value, and the logarithm of the final set value of the strobe value is increased by increasing the initial value of the strobe value with the logarithmic width of the sampling resolution as the number of tests increases. And a second calculating means for outputting to the integrated circuit test section for each test until the value of the strobe value becomes It can be done collectively sex measurement,
The work load of the operator is reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a DC characteristic analyzing apparatus for an integrated circuit according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing storage contents of a DC measurement condition memory in FIG. 1;

FIG. 3 is an explanatory diagram showing storage contents of a sampling time memory in FIG. 1;

FIG. 4 is a flowchart showing the overall operation of the DC characteristics analyzer shown in FIG.

FIG. 5 is a flowchart showing processing contents of a sampling time control unit in FIG. 1;

FIG. 6 is a flowchart showing processing contents of a strobe value calculation unit in FIG. 1;

[Explanation of symbols]

 Reference Signs List 10 Input device 12 DC measurement condition input unit 14 DC measurement start input unit 20 Integrated circuit test control device 22 DC measurement condition memory 24 Sampling time control unit 26 Sampling time memory 27 DC measurement display control unit 28 DC measurement result memory 30 IC test device 32 IC test part 34 Strobe value calculation part 36 DC measurement judgment limit memory 40 Display device 42 DC measurement result display part 44 DC measurement judgment limit display part

Claims (3)

[Claims] 1. A method for analyzing DC characteristics of an integrated circuit which measures a DC characteristic of an integrated circuit as a sample to be measured for each strobe value which is a measurement point on a time axis, and displays and analyzes the measurement result. From the data indicating the value range and the sampling number of the measured value of the DC characteristic, the logarithm of the initial setting value of the strobe value, the logarithm of the final setting value of the strobe value, and the logarithm of the sampling resolution in the DC characteristic measurement,
The logarithm of the initial setting value of the strobe value, the logarithm of the final setting value of the strobe value, and the initial value of the strobe value at the time of the DC characteristic test based on the logarithm of the sampling resolution, given by the logarithm of the initial setting value of the strobe value, With the increase in the number of DC characteristics tests, the initial value of the strobe value is increased by the logarithmic width of the sampling resolution for each test and updated until the logarithmic value of the final set value of the strobe value is reached. DC characteristics analysis method for integrated circuits. 2. An integrated circuit test section for measuring a DC characteristic of an integrated circuit which is a sample under test for each strobe value which is a measurement point on a time axis, and a measurement result of the integrated circuit test section is displayed on a display device. In the DC characteristic analyzing apparatus for an integrated circuit to display and analyze, the logarithm of the initial setting value of the strobe value in the DC characteristic measurement and the final First calculating means for calculating a logarithm of a set value and a logarithm of a sampling resolution; a storing means for storing a calculation result of the first calculating means;
The initial value of the strobe value at the time of the DC characteristic test is given by the logarithm of the initial setting value of the strobe value based on the storage content of the storage means, and the initial value of the strobe value is increased by the number of tests to obtain the logarithm of the sampling resolution. A second calculating means for outputting to the integrated circuit test section for each test until the value becomes a logarithm of the final set value of the strobe value by increasing the width, and a DC characteristic measurement analysis of the integrated circuit. apparatus. 3. The integrated circuit according to claim 2, further comprising display means for displaying a measured value of the DC characteristic test and judgment data indicating whether or not the measured value is within an allowable range. DC characteristics measurement analyzer.