JPS61149870A - Waveform analytic system - Google Patents

Abstract

PURPOSE:To minimize an error due to a drift by determining a reference level which is equal to a mean level obtained while current supply to a body to be measured is stopped and calibrating a signal level obtained by supplying a current thereafter. CONSTITUTION:It is confirmed that a power source 7 is off and then waveform data on the body 1 to be measured such as an electronic component is passed through a probe 2a and a signal detecting means 8 and A/D-converted by an A/D converting means 9, and then transmitted to a computer 3 by a transmitting means 10. Then, the mean value of data stored in memories 4 and 5 is calculated by a processor 6 and then the displacement S of a ground position set in waveform reading from the mean value is calculated and stored in a memory. Then, the power source 7 is turned on to fetch waveform data after the operation of the body 1 to be measured becomes stable and the displacement S is subtracted from those waveform data. Consequently, measurement data after an error due to the drift of a measurement system is removed is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field 1] The present invention relates to a waveform analysis system, and more particularly to a waveform analysis system that minimizes errors due to drift in a waveform measurement system.

[Prior Art] When waveform analysis is performed by a computer, a waveform storage device is used that can measure and store data regarding the waveform of an object to be measured and transmit the data to the computer.

However, the no-signal level of the measurement system including the probe fluctuates due to changes over time (drift).

In particular, with current probes, changes in the no-signal level occur quickly and are large.

Furthermore, even if the no-signal level is adjusted, current probes usually have the property of performing magnetoelectric conversion, so even if the current probe is placed at the actual measurement point, it will be slightly influenced by the environment.

On the other hand, to measure current, there are two methods: cutting off the connection to the device under test and connecting the current system to this part, or inserting a known low resistance in series with the device under test and measuring the voltage waveform at both ends. There is also a method of doing so, but adopting such a method has a large impact on the circuit system.

On the other hand, the method using a current probe involves cutting the wire,
It does not require any work such as inserting a resistor, and can be measured externally, so there is little impact on the circuit system.

For this reason, the method using a current probe is widely adopted, but it has the drawback that the no-signal level fluctuates due to drift as described above.

[Objective] The present invention has been made to eliminate the above-mentioned conventional drawbacks, and provides a waveform analysis system configured to minimize errors due to drift with an extremely simple configuration. The purpose is to

[Summary of the Invention] In order to achieve the above object, the present invention uses a waveform storage device that can transmit data to the outside, connects it to a computer, and records signals while the current supply to the object being measured is stopped. A configuration was adopted in which the average level of the signal was taken in as a reference, and then a current was supplied to calibrate the taken signal level.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

Figure 1 and the following diagrams explain one embodiment of the present invention.
The figure shows the schematic structure of the entire device.

In FIG. 1, the reference numeral l indicates an object to be measured such as an electronic component, which is a waveform storage device 2 that can transmit data to the outside.
The waveform data is captured.

This waveform storage device 2 also includes a probe.

The waveform storage device 3 is connected to the computer 3.

On the computer 3 side, there is a memory 4 for storing waveform data,
5 and a processor 6 which is an arithmetic processing unit.

Further, a power supply 7 that can be controlled by the computer is connected between the object to be measured 1 and the computer 3.

By the way, as shown in FIG. 2, the waveform storage device 2 includes a signal detection means 8, an A/D conversion means 9 for converting the analog signal detected thereby into a digital signal, and a means lO for transmitting data to the computer 3. It is equipped with

Furthermore, data receiving means 11 and correction means 12 are provided on the computer 3 side.

Next, the operation of this embodiment configured as above will be explained with reference to the flowchart shown in FIG.

That is, first, in step 51, it is confirmed that the power supply 7 is OFF, and then the waveform data of the object to be measured l detected and stored by the waveform control device 2 is imported into the computer (step S2).

At this time, the mode setting of the waveform storage device 2 may be such that, for example, the time resolution may be quite coarse without any problem, but the input signal sensitivity must be equal to that during actual measurement.

Then, in step S3, the average value A of the data acquired in this way is calculated, and then in step S4, the displacement S between the ground position set at the time of waveform acquisition and the average value A is calculated, and this is stored in the memory. I'll keep it.

Next, in step S5, the power supply 7 is turned on, and sufficient time is allowed until the object to be measured l stably operates, and after the operation becomes stable, waveform data is captured in step S6.

Subsequently, in step S7, the displacement S is subtracted from all of these waveform data.

Through such processing, measurement data from which errors due to drift in the measurement system are removed can be obtained.

Note that since the DC level of the measurement system is actually measured immediately before measurement, it can be assumed that the measurement data is at the same level as the DC ground level during actual measurement.

[Effects] As is clear from the above description, according to the present invention, data obtained when the power is OFF and when the power is supplied is acquired, and the data obtained when the power is supplied is corrected using the average value of the data when the power is OFF. Since this method is adopted, it is possible to eliminate errors due to drift in the DC level of the measurement system, and accurate waveform data can be measured.

[Brief explanation of the drawing]

The figures are for explaining one embodiment of the present invention. FIG. 1 is a block diagram explaining the overall structure, FIG. 2 is a block diagram explaining details of main parts, and FIG. 3 is a flow chart explaining processing operation. It is a diagram.

Claims (1)

[Claims] The waveform storage device includes a waveform storage device having a function of transmitting data to the outside, and an arithmetic processing device having a data receiving means and a storage means, and the waveform storage device has a signal detection means of the object to be measured and a signal waveform of the obtained signal. It has a time-series A/D conversion means and a time-series data transmission means, and calculates the average value of the data from the object under test when the power is OFF, and uses this average value when the power is turned off.
A waveform analysis system characterized by correcting data of an object to be measured in an N state.