SU1425723A1 - Voltage divider - Google Patents

Abstract

The invention relates to electrical computing devices and can be used in analog computers. The aim of the invention is to increase accuracy. Voltage divider contains main 1 and additional 2 scaling units, voltage follower 3, voltage source 4, load element 5, first 6 and second 7 keys, control unit 8, common bus 9, voltage extraction module 10, differential smoothing filter 11, voltage error amplifier 12, optocoupler unit 13, resistance-controlled element 14, reference voltage source 15, operational amplifier 16, first 17 and second 18 power sources. The operation of a voltage divider is based on changing the additional mass scaling unit 2 so that the voltage between the common bus of the voltage follower 3 and its output decreases. 1 il. to (L s

Description

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The invention relates to electrical computing devices and can be used in analog computers.

The purpose of the invention is to improve accuracy.

The drawing shows a functional voltage divider circuit.

The voltage divider contains a. main 1 and additional 2 scaling blocks, repeater 3. voltage, voltage source 4, load element 5, first 6 and second 7 keys, control block 8, common bus

 out bh /

to

one

(2)

where and, is the voltage between the non-inverting input of op amp 16 and the common bus repeater voltage.

In turn, the input voltage of the follower voltage 3 can be represented as a result of the influence of the common voltage from the outputs of the first 6 and second 7 cl10, i.e.

UBX, U5.-Uex

.K, U6v (1-K). (3)

9 voltage divider, voltage impulse unit 10, differential smoothing filter 11, error voltage amplifier 12, optocoupler unit 13, resistance-controlled element 14, reference voltage source 15, operational 16. Amplifier, first 17 and second 18 sources yitani /

The voltage divider works the following way.

The output signal from the control unit 8 closes the first 6 and second 7 keys.

If the instantaneous value of the voltage at the output of the source 4 of the voltage is positive, then the input of the repeater 3 of the voltage and on the load element 5 is positive. If the instantaneous value of the voltage at the output of the source 4 of the voltage is negative, then it is also negative on the load element 5.

The voltage follower 3 compares the voltage levels at the outputs of the first 6 and second 7 keys, chooses the difference of these voltages and summarizes the targeted voltage difference with the output voltage of the second key 7.

 Thus, the voltage level at load element 5 is almost equal to the output voltage of the main scaling unit 1,

and ue,

TO

one

(one)

UBX where and, is the voltage at the output of the second key 7j

the voltage at the output of the first key 6 ;, K is the transmission coefficient of the repeater 3, the voltage relative to its busbar, to it. The output voltage of the repeater 3 voltage can be written as

After the substitution (3) in (2) have and, s ,, Ue, (1-K,) - Kj. (four)

The voltage on the element 5 of the load is equal to the sum of the voltages (1) and (4),

then .,,

Uftb ,, - К, + и.Лт-к,) - к ,. (five)

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From the analysis of (5) it follows that the voltage follower 3 transmits to the load element 5 only a difference signal from the outputs of the first 6 and second 7 keys, such that the total voltage on the load element 5 is equal to the output voltage of the first key 6. Since the voltage drop on the first key 6 is close to zero, the voltage on the load element 5 is equal to the output voltage of the main scaling unit 1. This follows from (5) if K 1.

It is also seen from expression (5) that as an voltage follower 3, an operational amplifier with a small dynamic range can be used, since. only voltage is applied to its input

Uex (1-K,) K

(6)

If the transmission ratios of the main 1 and additional 2 scaling blocks are approximately equal, then K 1. Consequently, the dynamic range of the voltage follower 3 may be small.

At the same time, by the non-inverting input the shunting effect exerted by the repeater 3 on the output impedance of the main scaling unit 1 is minimized, and therefore, the high accuracy of the transmission coefficient of the main scaling unit 1 is ensured.

As the load current increases, the linear distortions of the additional scaling unit 2 and the repeater 3 increase, the voltage increases between the output bus of the follower 3 voltage across the common connection point of the power supply sources 17 and 18. This voltage is triggered by a module 10 allocation module. The key is connected to a common power bus.

voltage and supplied through a smoothing filter 11 to the input of the amplifier "12 voltage mismatch, the smoothing filter 11 in the opposite phase of its output voltage is supplied from the voltage source 15 of the reference voltage, therefore, a difference voltage acts at the input of the error voltage 12 15

a voltage follower, to the output of which a load element is connected, the control inputs of the first and second keys are connected to the output of the control unit, characterized in that; In order to increase the accuracy, a voltage modularization module, a differential smoothing filter, a source of pressure, which is amplified by them, and a power supply, the voltage amplifier are dissipated into the input buses of the optocne unit 13, for example, serially connected LEDs. Under the action of the light fluxes of the LEDs, the light-sensitive 1e elements, for example 25 photodiodes, generate phot-emf, which, acting on the control input of the element 14 with controlled resistance, for example, a field-effect transistor, changes the resistance between the drain-source electrodes. At the same time, the output voltage of the additional scaling unit 2 varies in the direction of reducing the voltage between the common connection point of the power supply sources 17 and 18 and the output bus of the voltage follower 3, and consequently, the high accuracy of the divider is ensured.

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35

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Variations, an optocoupler unit and a resistive-controlled element, the OTiopHoro voltage source, the first input bus of the voltage module having a common section connected to the common power bus of the voltage follower, the output of which is connected to the second voltage input bus of the voltage module, the output of which is connected with the first input of the differential smoothing filter, to the second input of which the output voltage of the reference voltage source is connected, the output of the differential smoothing filter is connected to the input of the voltage amplifier The first and second outputs of which are connected to the input buses of the optocoupler unit; the first and second output buses of which are connected to the first and second control unit, the element's tires with controllable resistance, the first information bus of which is connected to the second input bus of the additional scaling unit The second information bus of the element with controlled resistance is connected to the common bus of the voltage divider.

Claims (1)

Formula iso The voltage divider containing the main and additional scaling units, to the first input buses of which the first voltage source bus is connected, the second input voltage The width of the main scaling unit is connected to the second bus of the voltage source and is the common bus of the voltage divider, the output of the main scaling unit is connected via the first switch to the input of the voltage follower, the output of the additional scaling unit through the second a voltage follower, to the output of which a load element is connected, the control inputs of the first and second keys are connected to the output of the control unit, characterized in that; In order to improve accuracy, an voltage modulus allocation unit, a differential smoothing filter, and a source of reference 5 are introduced into it. 0 five 0 five Variations, an optocoupler unit and a resistive-controlled element, the OTiopHoro voltage source, the first input bus of the voltage module having a common section connected to the common power bus of the voltage follower, the output of which is connected to the second voltage input bus of the voltage module, the output of which is connected with the first input of the differential smoothing filter, to the second input of which the output voltage of the reference voltage source is connected, the output of the differential smoothing filter is connected to the input of the voltage amplifier The first and second outputs of which are connected to the input buses of the optocoupler unit; the first and second output buses of which are connected to the first and second control unit, the element's tires with controllable resistance, the first information bus of which is connected to the second input bus of the additional scaling unit The second information bus of the element with controlled resistance is connected to the common bus of the voltage divider.