SU752174A1 - Voltage comparator - Google Patents

Description

one

The invention relates to measuring, engineering, and can be used to automatically monitor and measure the voltages being tested. and reference lines, as well as fixing the degree of their deviation.

A device for comparing the voltage, which contains a differential amplifier, a current generator and a measuring element in the form of a tunnel diode 1, is known.

This device has a low measurement accuracy due to the instability of the parameters of semiconductor elements and, in addition, it cannot fix the degree of voltage deviation.

Closest to the present invention is a voltage comparison device, which contains a pulse generator, a time selector, the output of which is connected to the input of an output amplifier, input terminals for connecting sources of comparable voltages, two pairs of keys and two RC circuits 2.

A disadvantage of this device is that it cannot control the compliance of measurements with voltages with an established one.

and fix the degree of their deviation by the lower and upper limits. The purpose of the invention is to improve the accuracy of measuring the deviation of the tested voltage from the reference and fixing the degree of their correspondence.

This goal is achieved by the fact that, in a voltage comparison device containing input terminals,

10 connected to the checked and reference line and to the first inputs of the voltage comparators, a time selector whose output is connected to the display unit, and a pulse generator,

15, an inequality determination unit and a single vibrator, the output of which is connected to the first inputs of the time selector, the inputs of the inequality determination unit are connected to the outputs of the voltage comparators, and the output to the input of the single vibrator and the second inputs of the time selector, the output of the pulse generator is connected to the second inputs of the voltage comparators and the pulse generator is designed as a sawtooth generator & .

Fig, 1 shows a functional diagram of the proposed device

30 stress comparisons; in fig. 2 -

timing diagrams on circuit elements 1l;

The device contains terminals 1 and 2 for connecting the test and reference lines. Terminals 1 and 2 are connected to the first inputs of the comparators 3 and 4 voltages. A generator 5 of sawtooth voltage is connected to the second inputs of comparators 3 and 4. The outputs of the comparators 3 and 4 of the voltage are connected to the inputs of the inequality determination unit.6, the output of which is connected to the input of the one-vibrator 7 with adjustable pulse duration and the inputs of the time selector 8. The outputs of the time selector 8 are connected to the display unit 9.

The time diagrams (figure 2) show the voltage U | the tested line 1, the voltage U of the reference line 2, the voltage U at the output of the generator 5 sawtooth voltage, the voltage 1 at the output of the first comparator 3, the voltage 2 at the output of the second comparator 4, the voltage 3 at the output of unit 6 determining the inequality, the voltage 4 at the output of the one-oscillator 7 pulse selector, the voltage 5 on the input of the Go-on line, the display unit 9 and the voltage 6 on the input line of the Marriage of the display unit 9 of the display.

The voltage comparison device operates as follows.

The output voltages of the tested 1 and reference 2 lines are gated with a sawtooth voltage generated by the saw voltage generator 5 using voltage comparators 3.4. The output voltages of the comparators 3,4 are compared in duration with the help of the inequality determination block 6, the output pulse duration of which is proportional to the difference between the measuring 1 and the control 2 lines. The output voltage pulse of the inequality determination unit triggers the one-shot of the pulse selector 7 and enters the selection circuit 8.

Pulse selection circuit 8 consists of two circuits I. A pulse from the output of the one-shot 7 with an adjustable pulse duration and an inverse pulse from the output of the circuit 6 of unequality are fed to the inputs of the first circuit. Therefore, if the pulse from the output of circuit b of unequalities in duration is less than the pulse duration of the one-vibrator 7, then a voltage pulse appears at the output of this circuit And, the duration of which is equal to the difference of the pulse durations of the vibrator 7 and circuit unequalities.

The inputs of the second circuit And the selector 8 pulses receive voltage pulses from the output of block 6 determining the unequalities and inverse

impulse from one-vibrator output 7. Therefore, at the output of the second circuit I, a voltage impulse appears only when the impulse duration from the output of the inequality block b is greater than the impulse duration of the odouvibrator 7 (Fig. 2b).

By varying the pulse duration of the one-shot 7, one can thus change the degree of correspondence between the voltages tested 1 and the reference 2

lines with a predetermined accuracy.

The use of the proposed device in comparison with the known ones makes it possible to measure the voltage amplitude with a predetermined accuracy and to fix the degree of deviation of the tested and reference voltage by the upper and lower limits. Improving the accuracy of measurements is carried out by introducing a single vibrator with adjustable pulse duration, i.e. By varying the duration of the pulses, it is possible to set the percentage of deviation in the upper and lower limits of the measured voltage from the reference voltage. In addition, the proposed device makes it possible to compare synphase and pulse duration.

Claims (2)

1. A voltage comparison device containing input terminals connected to a test and reference line and to the first inputs of voltage comparators, a time selector whose output is connected to a display unit and a pulse generator, characterized in that in order to improve the accuracy of measuring the deviation of the tested voltage of the reference voltage and fixing their degree of correspondence, an inequality determination block and a one-oscillator are introduced, the output of which is connected to the first inputs of the time selector, the inequality determination block inputs are connected to the outputs of the voltage comparator, and the output to the input of the one-shot and the second inputs of the time selector, the output of the pulse generator is connected to the second inputs of the voltage comparators. 2. The device according to claim 1, which is based on the fact that the pulse generator is made in the form of a saw-tooth voltage generator. Information sources, taken into account in the examination 1. USSR author's certificate number 336604, cl. G 01 R 17/00, 1969. 2. USSR author's certificate number 395782, cl. G 01 R 17/02, 1970. m Uj P ") d ; fuz.S