SU658487A1 - Meter of threshold element hysteresis - Google Patents

Description

one

The invention relates to measuring equipment and can be used to create various automation devices, computing equipment and digital measuring devices for experimental research and monitoring of digital devices.

A hysteresis meter for horn elements is known, which contains a pulse generator connected to the input of the logic circuit I connected to the input of a reversible counter with its output connected to the input of the display circuit and to the input of the code-voltage converter whose output is connected to the input of the controlled comparator The second input of the latter is connected to the output of the voltage source, and the output is connected to the input of the meter. The output of the counter is connected to the control input of the indication circuit and to the reset input of the trigger. The reset input of the counter is connected to the output of the pulse generator, the other output of the trigger is connected to the second input of the logic circuit AND and to the input of the additional circuit AND, the output of which is connected to the control input of the controlled comparator, and the second input

additional circuit And connected to the output of the modulating signal generator 1.

However, this gauge is pretty

it is complex both in schematic and constructive execution, and also has insufficient measurement accuracy. Also known meter hister. POS element containing

an integrator, a source of alternating voltage, connected through an integrator to the input of a controlled threshold element, and two AND 2 logic circuits.

The purpose of the invention is to improve the measurement accuracy.

Claims (2)

This is achieved by the fact that the hysteresis meter of threshold elements, which contains an integrator, an alternating voltage source connected through an integrator to the input of a monitored threshold element, and two AND logic, is equipped with an inverter and a differential average voltmeter, while the output of the alternating voltage source is connected to the input of the circuit And through an inverter with the input of the second circuit And, and the output of the monitored threshold element is connected to the second inputs of the circuit, the outputs of which are connected to the direct and inverse To the inputs of a differential voltmeter of average value. The drawing shows the functional scheme of the proposed measure of the hysteresis of the threshold elements. This meter contains an integrator 1, a source of variable voltage-: NIN 2, connected via integrator 1 to the input of a monitored threshold element 3, and two logical circuits 4 and 5, as well as an inverter b and a differential average voltmeter 7. The output of the voltage source is connected to the input of the circuit AND 4 and through the inverter b to the input of the second circuit AND 5, and the output of the controlled threshold element 3 is connected to the second inputs of the circuits 4 and 5 whose outputs are connected to the direct and inverse inputs differential voltmeter 7 average. This meter works as follows. Due to the need to use integral estimates of the hysteresis of the threshold elements, the hysteresis value should be found as the difference between the average values of the thresholds of the slave where and is the threshold value at the bottom approach for the i-th trigger and its threshold value at the top of the i-th trigger R is the total number of operations. The alternating voltage source 2 generates a sequence of rectangular pulses with a duty cycle of two. These pulses enter the input of integrator 1, during which triangular pulses form. The parameters of the integrator 1 are selected so that the maximum voltage at its output exceeds the threshold value of the monitored threshold element 3. Therefore, the output of the monitored threshold element 3 will generate pulses whose duration will be equal to the time when the voltage of the integrator 1 exceeds the threshold values triggers when approaching from below and above. These pulses are fed to the inputs of logic circuits AND 4 and 5. The other input of logic circuit 4 receives impulses from an alternating voltage source 2, and the second input of logic circuit 5 receives impulses from an alternating voltage source 2 transmitted through the inverter b . Thus, at the output of logic circuit 4, pulses will form, the leading edges of which are determined by the leading edges of pulses 874 from the output of the monitored threshold element 3, and the rear edges - by the falling edges of pulses of the alternating voltage source 2. At the output of logic circuit 5, pulses will form , the leading edges {fronts of which are determined by the front edges of pulses from the inverter b, and the rear edges - by the falling edges of the pulses of the controlled threshold element 3. Therefore, the duration of the pulses at the output is one Logic circuit is proportional to the difference between the amplitude (apex) of the signal from inverter 1 and the voltage at which the controlled threshold element 3 triggered from the bottom, and the output of another logic circuit AND the difference of the same amplitude and tripping voltage of the controlled threshold element 3 at the approach from above. The difference between the pulse durations at the outputs of logic circuits 4 and 5 will determine the instantaneous value of the hysteresis. A differential voltmeter 7 connected to the outputs of logic circuits 4 and 5 measures the difference between the average value of the signal that came to one of its inputs and the average value of the signal that came to its second input. At a fixed amplitude of the pulses of the AND 4 and 5 logic circuits, these values are determined by the pulse durations. The hysteresis value, shown by a differential voltmeter 7, is buzet by its integral evaluation. Claims The hysteresis meter of threshold elements, comprising an integrator, a variable voltage source connected through an integrator to the input of a monitored threshold element, and two AND logic circuits, which is indicated by the fact that it is equipped with an inverter and a differential voltmeter to improve the measurement accuracy. mean value, while the output of the alternating voltage source is connected to the input of the AND circuit and through the inverter to the input of the second AND circuit, and the output of the monitored threshold element is connected to the second And circuit outputs, the outputs of which are connected to the direct and inverse inputs of a differential voltmeter of medium value. Sources of information taken into account in the examination 1. Interuniversity thematic scientific collection Analog-digital and digital-analog converters, Vol. 1, Taganrog, 1974, M.E. Beard, automatic digital, etc., a measuring instrument for studying some characteristics of comparing devices. 2. USSR author's certificate 420940, G 01 R 13/02, 1972.