SU995319A1 - Frequency-to-binary code converter - Google Patents

Description

The invention relates to the encoding, continuous non-electric quantities and can be used in measurement technology to create sensors of various physical quantities with the representation of the measurement result in binary code.

A known converter is a frequency ratio of a V. code containing pulse formers, counters, coincidence and absorption elements, keys, a delay element, and an output register of the SI rewriting.

This converter has low conversion accuracy.

The closest in technical terms to the present invention is a differential sensor signal converter, which contains two generator-controlled sensors connected to a pulse shaper, shapers of the first and second time intervals, consisting of RS flip-flops, two coincidence elements and C2D frequency dividers.

The formation of the measuring interval in this device occurs asynchronously with respect to the pulses of the reference frequency, which,

reduces accuracy, and the result of the conversion may contain a fairly large level of noise.

The purpose of the invention is to improve the accuracy and noise immunity in a wide frequency range. . . . This goal is achieved in that the frequency converter in. binary code containing the first and

Claims (3)

10 second pulse formers, a crystal, a generator, the first and second timed formers, the first input of the second of which is connected to the output of the second pulse generator, an output unit, a reversible counter, the outputs of which are connected to the information inputs of the overwriting register are entered a synchronization unit and a pulse distributor, the output of the crystal oscillator is connected to the first inputs of the control unit and the synchronization unit, the second input of which is connected to the output of the first generator pulses, A. output connected to the first input of the first time interval generator and C-input 7 of the distributor impulse &, the first and second inputs of which are co30 with the first outputs of the first and second time formers of the time interval, the second inputs of which are combined and connected to the first output pulse distributor and R-input of a reversible counter, the summing and subtracting inputs of which are connected respectively to the first and second inputs of the control unit, the second input of which is connected to the third century of the first Forming the time interval with its second output, the third input of the control unit is connected to the third input of the second time interval generator and its second output, the second output of the pulse distributor is connected to the control input of the rewriting register. The time interval former contains two trigger elements and a frequency divider, with the first input of the first element matching either connected to the first input of the driver, and the S input of the trigger, whose R input is connected to the second input of the driver and the R input of the frequency divider. the input of which is connected to the output of the first coincidence element, and the direct output is the first output of the driver, the inverse output of the frequency divider is connected to the first input of the second coincidence element, the second input of which is connected to the direct output the trigger, and the output is the second output of the imaging unit, the second input of the first matching element is connected to the third input of the imaging unit. In addition, the control unit contains two elements of a match and a prohibition element whose output is connected to the first inputs of the matching elements, the second inputs of which are combined and. Are connected to the first input of the block, the second input of which is connected to the third input of the first matching element and the first input of the element the prohibition, the second input of which is connected to the third input of the second match element and the third input of the block, the outputs of the first and second match elements are respectively the first and second outputs of the block. 1 shows a block diagram of a converter; 2, a timing diagram explaining the operation of the proposed device. The converter contains a crystal oscillator 1, drivers 2 and 3, a time interval driver 4, which includes elements 5 and 6 of coincidence, frequency divider 7 and trigger 8; a time interval generator 9 comprising coincidence elements 10 and 11, a frequency divider 12 and a trigger 13, a control unit 14 including a prohibition element 15 and coincidence elements 16 and 17, a synchronization unit 18, a reversible counter 19, an overwriting register 20 and a pulse distributor 21. The device works in the following manner. Let the output frequencies and Fx2 and their periods be equal to each other in the middle of the range of variation of the parameter being measured. The output frequency P of the first measuring channel and the periods Tx of the second are large in one half, and the output frequency Fj (2 of the second and periods Tjf of the first measuring Kangshov are large in the other half of the range of variation of the measured parameter (Fig. 2, i-th and j- cycles). In the initial state the triggers 8 and 13, the dividers 7 and 12 frequencies and the reversible counter 19 are in the zero state. Accordingly, at the outputs of the formers 4 and 9, the time interval, i.e. at the outputs of elements 6 and 11 coincidence, the presence of, 0., and the frequency pulses from the output form world exporter 3 (FIG. 2 e) and frequencies F from the output of synchronization unit 18 (FIG. 2B) to the inputs of dividers 12 and 7, and from the output of the crystal oscillator 1 to the inputs of the reversible counter 19 are not received. frequency Fx- (Fig.2) to the pulses (Fig.2 ") of the quartz oscillator 1. It can contain two triggers and a block of matching elements and is designed so that instead of each of the input pulses it produces a pulse (Fig.2 in) that coincides with one of the pulses of the crystal oscillator 1. The first of the input pulses of frequency F, (and Fx2 translate t ggery 8 and 13 in a single state, which results in the appearance on the outputs of elements 6. and 11 matches levels, forming a first start (2 t) and the second (x 2) timeslots. All subsequent frequency pulses F x1 (Fig.2 E and 3) are received at the information inputs of the dividers 7 and 12 frequency. Since the capacities of the dividers 7 and 12 are the same frequency, and the periods of the input frequencies FXI and Fx2 are different, the time t NQT, (and t, after which the logical levels change at their outputs, is not the same. In the iM cycle, and in jM cycle t. Changing logic levels At the outputs; frequency dividers 7 and 12 result in the output of the formers 4 and 9 of the time interval of levels and at the inputs of the distributor 21 level pulses 1. Let the first (smaller) time interval be in the 1st cycle t (FIG. 2 g will start forming earlier than the second (larger) tz (FIG. 2, h), and in the JM cycle, on the contrary, the first (longer) t (Fig. 2d) will begin to form in the same way as the second (smaller) t2 time interval (Fig. 2;). Then, for a time LU equal to the interval between the beginning of the formation t (second t2 and second 12 (first C) time intervals (in the i-th cycle of FIG. 2 and, in JM - FIG. 2 k), to the summing input (in the iM cycle) and subtracting input (in the JM cycle a) reversible counter 19 will arrive respectively N and N; f pulses of the quartz oscillator 1 (FIG. 2 y in the 1st and. 2 m in jr-M cycles), where NlJ N is the number of pulses received, respectively, on the summing or subtracting input of the reversible counter at the beginning of the conversion cycles; Fpg - frequency of the crystal oscillator l. Starting from the moment when the outputs of the formers 4 and 9 time intervals appear H, and until the end of one of them, the pulses of the crystal oscillator 1 (figure 2 ct) do not arrive at the inputs of the reversible counter 19. From the moment of the end of one of the time intervals (in the ith cycle of the first in J-M - the second) and until the end of the other (in the i-M cycle of the second in J-M of the first), i.e. during dT2- () for i-ro cycle (Fig. 2 k) and / sC2 t - t2 + dTi) for j-ro cycle (Fig. 2 m), to the input of the subtraction (i-th cycle, Fig. 2m ) and the summing input (jth cycle, Fig. 2 l) of the reversible counter 19 will receive the number of pulses received, respectively, to the summing or subtracting input of the reversing counter at the end of the conversion cycles. The output code Ngbrx is equal to the number of pulses received during the time T-t, i- (ti-uT +) .- aT + to the subtracting input (for the i-ro cycle) and С ti- (t2 + ur;) + dt; ti-t2 to the summing input (dp j-rp cycle) of the reversible counter 19, i.e. to-t: bt o6P and Neb, xj (t -t2rFoyp (...), will determine the output 2- 1 2.j.:,.- „. flaccion as the modulus of the difference between longer and shorter time intervals; At the time of the end of the formation time intervals (Figures 2 and o). The levels of the distributor 21 appear at the same time. At the time of the occurrence of "1, an informational C input opens at both inputs (Fig. 2n), which receives the current frequency value of the first signal , synchronized pulses kzvartsev generator 1 (Fig. 2). The first output pulse of the distributor 21 (Fig. 2 p) rewrite (two of them are: a Supported rev.ersive counter and 19 into a register 20. The second output pulse (Fig. 2c) sets to zero the dividers 7 and 12, the reversing counter 19 and the triggers 8 and 13, which corresponds to the beginning of the next conversion cycle. Thus, in the proposed converter, to increase speed, measurement of the difference between the periods of the current values of the frequency of the differential sensor. In each conversion cycle, the result is equal to the number of pulses of the quartz oscillator 1 received at the inputs of the reversible counter 19 during the time defined as the difference module and between the larger and smaller of the time intervals, formed independently of each other. The ability to discretely change the numerical capacitances of the frequency dividers makes it possible to obtain the required conversion scale of a measurable quantity — a binary code. The use of the synchronization unit of one of the signals and its use for generating control pulses stabilizes the operation of the converter and significantly reduces the noise level at the output of the device; the formation of independent time intervals and the execution of both measuring channels of the differential frequency sensor identical., Pos. They will best compensate for the effects of destabilizing factors and improve the accuracy of the transformation. With this, the device performs full processing of frequency information, which is very convenient to use. Claim 1. Frequency converter in binary code, containing first and second pulse shapers, crystal oscillator, first and second time interval shapers, the first input of the second of which is connected to the output of the second pulse shaper, control unit, reversible counter, the bit outputs of which are connected with the information inputs of the register of rewriting, about tl and h a y i and so that, with In order to increase accuracy and noise immunity in a wide frequency range, a synchronization unit and a pulse distributor are entered into it, the output of the crystal oscillator is connected to the first inputs of the control unit and the synchronization unit, the second input of which is connected to the output of the first pulse former, and the output is connected to the first input of the first time generator, but, the first interval, and the C input of the distributor, impulse, the first and second inputs of which are connected to the first outputs, respectively, of the first and second firs vr.emennogo interval, the second inputs of which are combined and connected to the first output of the pulse distributor and R-input of down counter summiruyushy vElchitayuschy and whose inputs are connected respectively to -.pervomu and second inputs of the control unit; the second input of which is connected to the third input of the first temporalizer and its second output, the third input of the control unit is connected to the third input of the second time-former and the egp output, the second output of the pulse distributor is connected to the control input of the relay register records .. .--. ..... 2. The converter according to claim 1, 1 and 2 of t. .em that. the time interval generator contains two coincidence elements, a trigger and a frequency divider, the first input of the first element being the same, which is connected to the first input of the driver and the S input of the trigger. The R-input of which is connected to the second input of the rapper and the R-input of the frequency divider, the C-input of which is connected to the output of the first coincidence element, and the direct output is the first output of the Shaper, the inverse output of the frequency divider pod1) match element, the second input of which is connected to the forward trigger output, o and the output is with the second output of the driver, the second input of the first ale. The match point is connected to the third input of the driver. 3. The converter according to Claims, .1, O t 5, and so that the control unit, contains two elements of coincidence and the element of prohibition, output. . which is connected to the first inputs of a match, the second inputs 0 of which are combined and connected to the first input of the block, the second; the input of which is connected to the third in; one the first element of the coincidence element and the first input to the banning tape, the second 5 which INPUT, is connected to the third the input of the second match element and the third input of the block, the outputs of the first and BTOpoiO coincidence elements are respectively the first and third Q output of the block. . , Sources of information taken into account in the examination 1, GaEBo M., WinkEer I. Mikroproz zessoren im Waagenbeh, Fein.werkteqhnik und Messtechhik, 1978, No. .1, S. 30-35, 2.Novitsky P.V. And others. Digital devices with frequency sensors. L., 1970, p. 342-345. Energy (Pt / f.f but s e well 3 and to l n / g fl s