SU748290A1 - Device for measuring statistical characteristics of switching-over elements - Google Patents

Description

(54) DEVICE FOR MEASUREMENT OF STATISTICAL CHARACTERISTICS OF SWITCHING ELEMENTS

one

This invention relates to a measurement technique. The device can be used to measure and study the statistical characteristics of switching elements in the 5 pulse mode in the nanosecond range.

A device for investigating statistical regularities of switching elements based on glassy semiconductors containing a microsecond pulse generator, a trigger generator, a logic circuit, and a multichannel analyzer is known. Its disadvantage is that it cannot work in the nanosecond range.

It is also known a device for investigating the statistical characteristics of switching elements under the influence of nanosecond pulses, which contains a generator of nanosecond pulses, a transmission line and an oscilloscope with a real time scale of 25 time 2. its disadvantage is a considerable time for obtaining the results of statistical analysis with a limited number of test pulses.

The aim of the invention is to increase the measurement performance by obtaining a large volume of realizations in a short time.

The goal is achieved by introducing a pulse counter, level selector, gating unit, and strobe generator and pulses into the device containing the nanorecond pulse generator, the output of which is connected to the synchronization input of the oscilloscope directly and through the transmission line to the input of the device and the signal input of the oscilloscope. connected to the output of the generator of nanosecond pulses, and the output of the generator of gating pulses through a serially connected gating unit and level selector connect It is connected to the input of the pulse counter, while the analog input of the gating unit is connected to the output of the specified oscilloscope, completed with a strobe.

FIG. 1 shows the block diagram of the writeable device; Fig. 2 shows a timing diagram — the dependence of the measured pulse voltage on time.

The device contains a generator of 1 nanosecond pulses, a transmission line 2, a stroboscopic oscilloscope 3, a generator of 4 gating pulses, a gating unit 5, a level selector 6, a counter 7 of pulses, and a switching element 6 under study.

The principle of operation of the device is as follows.

 Switching the pulse generator 1 pulse, passing through transmission line 2 in 60 ns, goes to switching element 8. After switching, the reflected pulse goes to oscilloscope oscilloscope 3 (pulse oscillogram is shown in fig.2c |), it is tuned by means of manual sweep its analog output was recorded by the r1-amplitude of the reflected pulse at a certain time point to (Fig. 2a). In such a case, its value depends on the delay time of the switching process tr. From FIG. 2о | it can be seen that switching with the delay time -c on the analog output of the oscilloscope 3 gives a pulse with amplitude Ug. , and with -ed and t g - with amplitude J. Since each switching pulse gives a different holding time, the analog output has the following: step voltage, which is proportional to the delay time, and the duration of the steps is determined by the repetition frequency of the switching pulses (in the case of a frequency of 200 Nt. For 4 ms, Fig. 2 (J).

The step voltage is applied to the gating unit 5. The gating pulses (Fig. 2c) generated by generator 4, synchronously triggered from the nanosecond generator 1, also flow to the gating unit. As a result, a series of pulses appears (Fig. 2d), the amplitude of which is modulated by the dypening voltage (fig.) and, therefore, proportional to the delay time.

The Level B selector only passes those pulses whose amplitude lies in a certain pre-selected voltage range dC O (Fig. 2d. Therefore, the impulse counter 7 receives impulses which are equivalent to switching between 40 and W). The pulse counter It is necessary to count the number of switchings for a certain time span (for example, 1 minute) with a predetermined delay time. This number is proportional to the probability

occurrence of switching with a given delay time, which azn jfcg.2Q). If the value is to, it is possible to determine the probability for different tr. i.e. build a histogram.

In order to study the statistical characteristics, for example, the resistance of the conductive Pn, to is chosen so that it is greater than the maximum delay time. Then change

position of the recording interval

About whether O with respect to the pulse, you can build a histogram for ylr.

The advantage of the proposed device is that the histogram of the distribution of the voltage of the pulses can be built in a relatively short time (within 1020 min). In this case, the implementation contains 10 pulses. In the known device, the preparation of histogram takes 5 hours and contains only 500 pulses. The device can be used for on-line measurements of the statistical parameters of the delay time and the resistance of the on state of the semiconductor element. When you connect the device to a punch computer, the speed of information processing can be increased.

Claims (2)

1.Journal NeMrC Jstal Solids, vol. 17, 2, 1975, p. 189. 2. Technical Physics, vol. 37, 1967 (prototype), ff f Tg R 6 i, nc