SU764127A1 - Analog value-to-code converter - Google Patents

Description

one

The invention relates to devices converting electrical quantities into digital form, and may be used, in particular, to measure the duration of an impulse; 1, a period, and a pulse frequency.

In addition, the transducer can be used to create measuring instruments and sensors operating on the background of noise and interference. ten

A device is known that contains an exemplary frequency generator, a control unit made on the control triggers, keys made on the AND elements, a driver 15 pulses, summing and reversing, counters jl. The disadvantage of this device is a small coefficient of averaging, which determines the noise immunity and accuracy of the device 20, since in the final result, only the first and last results of single measurements are practically taken into account. In addition, the known device has a complex circuit and 25 has a low speed.

The closest in technical essence to the present invention is a device comprising a forming device, an oscillator thereof.

pulses, electronic keys, summing and reversing counters, control device and pulse distributor 2. The disadvantage of the known device is the low speed, due to the fact that the information B1 is given only in certain time points determined by the number of averaged EH periods. In addition, since the weight of the quantization result is variable, the weight of the error due to the noise of I.PI noise is also variable, which leads to the appearance of large measurements.

The aim of the invention is to improve the accuracy, noise immunity, speed of the converter.

The goal is achieved by the fact that the device containing the generator of exemplary frequencies, the outputs of which are connected to the inputs of the control unit, the first and second outputs of which are connected respectively to the inputs of the driver and the first input of the first key, the third output of the control unit 11 is connected to the first input of the second key and the second input of the first key, the counter-register, the counting input of which is connected to the output of the Bloporo key and the reversible counter, are entered the elements of coincidence of the inverter and the frequency divider, to the inputs of which About the outputs are connected, the keys, the outputs of the frequency divider are connected to the inputs of the reversible counter, the outputs of the bits of which are connected to the inputs of the corresponding bits of the counter register, the outputs of the counter register are connected to the inputs of the match element whose output is connected directly to the second input of the second key and through the inverter to the third input of the first key, the output of the pulse generator is connected to the control input of the counter-register. The drawing shows a structural circuit converter. The converter contains a generator of reference frequencies 1 connected to the control unit 2, which consists of switches 3 and 4, setting the required operation mode; pulse generator 5, counter-register b, coincidence element 7, inverter 8, two keys 9 and 10 regulating the frequency divider of impulses 11, reversible counter 12 and output register 13. Conversion sources are connected to the inputs of the control unit, Switches 3 and 4 in the drawing are shown in the position of the pulse width to code converter (pulses can follow periodically or in any other way). From the output bits of the reversible counter, the output code of the converter is removed, which can be stored, for example, in the output register, or directly transmitted to display systems, printing systems, and the like. The converter works as follows; shimm way. The input impulse with the leading edge through the pulse shaper 5 is implemented in the counter-register b of the halved result of the previous conversion, which is stored in the reversing counter 12. At the same time, the result of the previous conversion is recorded in the OUTPUT register 13. If present in all output bits a high-potential counter-register region at the output of the coincidence element 7 appears a zero signal; otherwise, the output of the coincidence element 7 appears a single signal. ; Pulses of exemplary frequency f, from the generator of exemplary frequencies 1 through the closed contacts of the switch 4 of the control unit 2 and the key 9 is opened to the counting input of the counter-register 6 c reduced by the K frequency divider 11 to the subtracting input of the reversible counter 12. After the passage of the number of pulses of the reference frequency, equal to half of the previous measurement result, the counter-register b counts to zero, the Coincidence element 7 is triggered, the key 9 is closed and the key 10 is opened, which remains open until the input risutstvuet input pulse. In this case, the pulses of the exemplary frequency from the generator of the exemplary frequencies 1 through the key 10 and the frequency divider 11 are fed to the input of the reversing counter 12 for summation. Thus, if there is a change in the duration of the input pulse, then by the end of the pulse to the reversible counter 12 the difference between the value of the previous measurement and the value of the newly received input pulse, reduced by K times, which is added to its sign with the result of the previous measurement. If this input pulse duration is preserved, then after a certain number of periods a new measurement result is established, since the difference between the value of the previous measurement and the new value of the input pulse will be of the same sign and will decrease with each peri-V period until it becomes zero. In the event that the duration of the input pulse changes as a result of toyMa, the difference between the value of the previous measurement and the new value of the input pulse will have an alternating character. Noise will be imposed on the measurement result, but will be reduced by a factor of K. The conversion of the pulse following period into a code is performed when the switch 3 is switched in the control unit 2. In this case, the first input of the switch 10 all the time passes to pass. pulses, which ensures the continuity of the transformation, which is carried out as in the previous case. The code is written in the output register 13 by the leading edge of the incoming pulses. The pulse frequency is converted into a code when the switches 3 and 4 of the control unit 2 are switched. In this case, the generator of the reference frequencies 1 receives the pulses 5, for example, the frequency F 1 Hz, and the third key input 10 and the first key input 9 the impulses of the converted frequency f,. Otherwise, the operation of the converter is similar to the previous cases. Thus, in this device, the error of the converter, caused by noise or interference, is included in the count reduced K times; The final sample contains information about all previous samples with decreasing weighting coefficients, and the earlier the pulses, the less their contribution J the output code. The information is updated after the arrival of each pulse.

This makes it possible to increase the accuracy of converting input measured values against noise and noise, and also allows creating a universal device for converting duration, frequency, period, and the ratio of two frequencies to a code. In addition, in this device it is possible to adjust the frequency division factor, which allows changing the degree of averaging of the conversion result, and updating the information after each new value of the measured value allows to judge the process dynamics.

Claims (2)

Invention Formula Converter analog values in the code containing the generator of exemplary frequencies, the outputs of which are connected to the inputs of the control unit, the first and second outputs of which are connected respectively with the input of the pulse generator and the first input of the first key, the third output of the block control is connected to the first input of the second key and the BTopoviy input of the first key, the counter-register, the counting input of which is connected to the output of the second key, and a reversible counter, characterized by the fact that, in order to improve accuracy, noise immunity and performance, the element coincidence, inverter and divider; frequencies, to the inputs of which are connected the outputs of the keys, the output of the divider 0 frequencies are connected to the inputs of the reversible counter, the outputs of the bits of which are connected to the inputs of the corresponding bits of the counter-register, the outputs of the counter-register are connected to the inputs of the matching element whose output is connected directly to the second input of the second key and through the inverter to the third input of the first key , the output of the pulse former is connected to the control input of the counter-register. Sources of information that are considered in the examination 5 1, USSR Author's Certificate I 507933, MKI 03 K 13/20, 1976. 2. USSR author's certificate In 513343, MKM Q04 F 1 & 04, 1976.