SU1045381A1 - Voltage/frequency converter - Google Patents

Abstract

VOLTAGE EQUIPMENT E. FREQUENCY, containing the first integrator, the first input of which is connected to the first input bus, the second input to the output of the reference voltage source through the first resistor and the first switch connected in series, and the output connected to the input of the first threshold element, and the reference frequency generator J- the output of which is connected to the first input of the pulse distributor, characterized in that, in order to expand its functionality, the third keys, the second and third threshold elements are entered into it by the agora , the first, second and third R9-triggers / voltage divider, the first, second and third elements And the second and third resistors and the second integrator, the output of which is connected to the inputs of the second and third threshold elements, the first input through the second resistor is connected to the second input bus, the second input through a series-connected third resistor k.: gh. ;.}. l is connected to the output of the voltage source, and the third input is connected to the midpoint of the voltage divider, the outputs of which are connected respectively to the outputs of the second integrator and the voltage source, and the S input of the first H5 flip-flop is connected to the output of the first And element, inputs which is connected respectively to the outputs of the first threshold element and the reference frequency generator, and the R input is connected to the direct output of the second trigger and the first input of the second And element, the second input of which is connected to the output of the third its threshold element and to the first input of the third element I, the second input of which is connected to the inverse output of the second R-trigger, and the output to, S-input of the third H5 trigger, input of which is connected to R, -the input of the second RS trigger and with the second element gouging out, and the output with the control input of the first key, the control input of the second key being connected to the output of the pulse distributor, the output bus and S to the input of the second Ri-flip-flop, and the control input of the third key is to the inverse output of the first, R5-flip-flop.

Description

The invention relates to information technology and instrumentation technology and is intended for use in automation devices, tel1: mechanics, in power engineering for determining power and energy consumption, and in other sectors when it is necessary to convert the product of two voltages into frequency A converter is known in which obtaining an output frequency proportional to the product of two input voltages is achieved by using a functional voltage transformer in the time interval Ij in the pulsed feedback circuit. The disadvantage of the device is low accuracy. A converter is known, directly or not to the frequency, containing the first integrator, the first input of which is connected to the first input bus, the second input is connected to the output of the reference voltage source via serially connected first resistor and First key, and the output is connected to the input of the first threshold element, and the reference frequency generator, the output of which is connected to the first input of the pulse distributor C 2, Its disadvantage is the limited functionality as it is is meant for the converter to the frequency of only one output voltage. The purpose of the invention is to expand the functionality of a voltage to frequency converter. The goal is achieved in that the voltage to frequency converter contains the first integrator, the first input of which is connected to the first input bus, the second input is connected to the output of the voltage source through the first resistor and the first key connected in series, and the output is connected to the input the first threshold element, and the reference frequency generator, the output of which is connected to the first reversible input is connected to the first input of the pulse distributor, the second and third keys, the second and third threshold elements, the first , second and third RB trigger lL, voltage divider, first, second and third elements AND; the second and third E) resistors and the second integrator, the output of which is connected to the inputs of the second and third threshold elements, the first input through the second resistor is connected to the second input bus, the second input is connected through the third resistor connected in series and the second switch is connected to the output of the source -1nik reference voltage the third input is connected to the midpoint of the divider; april, the outputs of which are connected respectively to the outputs of the second integrator 1 and the source of the reference voltage, moreover, S is the input of the first Rc, and the grigger is connected to the output the first- AND gate whose inputs are respectively connected to the outputs of the first threshold element and the reference oscillator, and I-INPUT is connected to the direct output of the second flip-flop and nepsBv; FJXO house of the second element And, the second input of which is connected to the output of the third threshold element and to the first input of the third element And, the second input of which is connected to the inverse output of the second RS flip-flop, and the output to the S-input of the third and -trigger whose R input is connected to R is the input of the second p.) - trigger and with the output of the second element I, and the output with the control input of the first key, while the control input of the second key is connected to the output of the distributor: pulses, output bus and S - input of the second RS- trigger, and the control input of the third key - to inverse output of the first R.S trigger. 1, the converter circuit is presented; Fig. 2 shows voltage diagrams for operation of the device. The converter contains the first input bus 1, connected to the first input voltage source, the first threshold element 2, the input of which is connected to the output of the integrator 3, the oscillator 4 of the reference frequency, the output of which is connected to the first input of the distributor 5 pulses ;, - key 6, the outputs of which are connected to the input of the first integrator .3, respectively, and through the first resistor 7 to the source 8 of the reference voltage. The converter also contains the second integrator 9, the second; 0 and third 11 keys, the second 12 and ii 13 threshold elements, the first, second and third RS-triggers 4 15, the output bus 17, the HI key; u s:; the output of the distributor 5, ne; rB:;: y, the second and third clementa And 13 - 2C,. the input of the integrator 3 is connected via a resistor 21 and i iepes input bus 22 to the second input voltage source, and through a switch 10 connected in series with power 23 to a source 8 of the reference voltage, and via switch 11 to a medium; ;;: the point of the voltage divider 24 ;;; which is connected: to the source 8 of the reference voltage and to the output of the integrator E, connected to the input voltage ;; threshold elements 12 and 13 The output of the threshold element 2 is connected to the first; at the input of the element I-18, Ztors; G whose input is connected to Bykho ;: C1-l of the driving frequency 4 of the reference frequency,; -. Schedule with S-input R5-flip-flop 14, the icer-icer Top connection is connected to the control input of the key 11, and the R-input to the forward output of the RS flip-flop 15. The output of the threshold element 13 is connected to the inputs of the And 19 and 20, the other inputs of which are connected respectively to the inverse and direct outputs of the R-trigger 15, the G-input of which is connected to the output of the distributor 5 pulses and to the control; entry -key 10. B-input K, 9-flip-flop 16 is connected to the output of the element I 19 and B-IKHOD - to the output of the element I 20 and to 1, - BHOD RS RS of the trigger 15, and direct output to the control input of the first key 6. The converter works the following in a way. The voltage of the first input source (Fig. 2a) is supplied through the first input bus 1 to the input of the integrator 3, while, when the key is 6 times the whip, the voltage at the integrator's output increases (Fig. 2c). When the voltage at the output of the integrator 3 reaches the threshold of the threshold element 2, a pulse is formed that opens the switch 6 to reset the capacitor of the integrator 3 with the voltage of the source 8 of the reference voltage through the resistor 7. Before the specified pulse is generated, the RS-triggers 14-16 are in the state of logical logic, keys b to 10 are open, and key 11 is closed. In this case, the integrator 9 operates in the mode of a mastable amplifier, its output voltage (initial voltage of the integrator) is determined; the ratio of the resistances of the resistors of the divider 24 is formed. The restart pulse of the integrator 3 is formed as follows. The signal from the output of the threshold element 2 opens the first input element And 18, the next impulse, from the pulse generator 4, arriving at the second input of the element And 18, passing Dlig to the output of the last and to the Pz-flip-flop 14 In this case, the inverted legs The output of the R.5-flip-flop 14 is set to a logical zero voltage (FIG. 2G), so the third key 11 is broken, the integrator 9 is switched to the integrated mode of the second output voltage. When the voltage n of the output of the integrator 9 reaches the level n of the operation of the threshold element 13 (Fig. 2d, level 25), the voltage at the output of the latter abruptly goes from one state to another. Ele: —ent I 19 at this time is open at the first input with a voltage from the injector; R9j-trigger 15, and the element And 20 is closed with a voltage from the direct output. Therefore, the pulse front of the threshold element 13 enters. through element 19 on the 5th input of the Trigger R5 16, putting it into a single state (FIG. 2e). This opens the key 6 and begins recharging the integrator 3 with the reference current (Fig. 2c). As the voltage increases at the output of the integrator 9, the instant of triggering of the threshold element 12 occurs (Fig. 2g, level 26). The voltage from its output goes to the second input of the pulse distributor 5, the output of which produces a pulse of the reference duration (Figure 2e). For the duration of this pulse, the key 10 opens, producing a reference recharge of the integrator 9 (Figure 2d). The pulse of the reference duration is also supplied to s, the input of the R trigger 15, as a result of which the RS ends the trigger 15 is turned into a single state (Fig. 2i). After the reference reset, the voltage at the output of the integrator 9 rises again until it reaches the trigger level of the threshold element 13 (Fig. 2d, level 25). The voltage at the output of the latter increases again in a jump-like manner (Fig. 2k), H5-flip-flop 16 goes to the state of logical zero (Fig. 2e), the key 6 closes. The impulse from the output of the element And 20 also enters the P-input of the RS-flip-flop 15, transferring it to the state of logical zero, while the--trigger 14, controlled by the R-input voltage from the output of the S-flip-flop 15, also goes to logical zero state. The key 11 closes the voltage at the output of the integrator 9 is reset (Fig. 2d). Then the process repeats, dpn the time interval between the moments of passing the Incremental Escress at the output of integrator 9 through orog trigger threshold element 13 (fig. 2d, level. 25) equal to the duration and; .- pulse compensation of the first integrator S (fig.2d) , the ratio is valid (for the steady state mode) -H, Uv, -TgUoRx ,, Cl) where 1 is the pulse duration at the output of the distributor 5; resistance of resistors 21 and 23, respectively; CBO - input and reference voltage. The pulse frequency of the second integrator's compensation pulses is defined by the expression 1 / tUo where Ux is the input voltage; n C are the resistances of the first input of integrator 3 and resistor 7, respectively.

Excluding V from expressions (1) and (2) we get

,

.- UviUs

(g)

As can be seen from expression (3), Ebikofl the frequency of the converter is proportional to the product of two input voltages. The conversion factor includes resistors, a reference interval, a reference voltage, and no integrator time constant. Since the accuracy of the realization of the value of the reference voltage, the reference frequency and the resistance can be high, the above-proposed device provides a high accuracy of converting the product of two voltages to the pulse frequency.

If it is necessary to obtain an output frequency proportional to the square of the input voltage, it is enough to connect the first and second input buses with a jumper.

Thus, thanks to the proposed differences, the functionality of the transform is expanded,

U-j-oa .and

eight

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TO

- y: n

-

Jul

(pi / c-.f

Claims (1)

(5 4) A FREQUENCY VOLTAGE CONVERTER, comprising a first integrator, the first input of which is connected to the first input bus, the second input to the output of the reference voltage source through the first resistor and the first switch connected in series, and the output is connected to the input of the first threshold element, and the reference generator frequency, the output of which is connected to the first input of the pulse distributor, characterized in that, in order to expand the functionality, the second and third keys, the second and third threshold elements, the second, second and third R5 triggers, voltage divider, the first, second and third elements And, the second and third resistors and the second integrator, the output of which is connected to the inputs of the second and third threshold elements, the first input through the second resistor is connected to the second input bus, the second input through a series-connected third resistor and ./pro; connected to the output of the reference voltage source, and the third input is connected to the midpoint of the voltage divider, the outputs of which are connected respectively to the outputs of the second integrator and the reference voltage source, and the 6-input of the first short-circuit trigger is connected to the output of the first AND element, the inputs of which are connected respectively to the outputs of the first threshold element and the reference frequency generator, a R-input connected to the direct output of the second trigger and the first input of the second element And, the second input of which is connected to the output of the third threshold of the second element and to the first input of the third element AND, the second input of which is connected to the inverse output of the second RS-trigger, and the output to the S-input of the third RS-trigger, R-input. which is connected to the R-input of the second R $ -trigger and with the output of the second element And, and the output with the control input of the first key, while the control input of the second key is connected to the output of the pulse distributor, the output bus and the S-input of the second RS-trigger, and the control input of the third key is inverted the output of the first, R5-trigger.