SU1598134A1 - Measurement converter - Google Patents

Abstract

The invention relates to a measuring technique and can be used in computing and measuring devices in control and automation systems. The purpose of the invention is to expand the operating frequency range of the device. The measuring amplifier contains an input pulse shaper 2, a frequency selector 5 and an OR element 8. To achieve the goal, an electronic switch 3, a peak detector 6, a pulse shaper 4 and an analog-to-digital converter 7 are entered. This allows measurement of the amplitude value of the input signal when changing the period of its following, regardless of the frequency of this signal. 4 il.

Description

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Fig, 1

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The invention relates to a measuring technique and can be used in computing and measuring devices in control and automation systems.

The aim of the invention is to expand the operating frequency range of the device.

FIG. 1 is a circuit diagram of a converter; in fig. 2 is a timing diagram explaining his work; in fig. 3 is one of the specific examples of the performance of the frequency selector; in fig. 4 - time diagram of his work.

The measuring transducer includes an input bus 1 connected. with the input driver 2 pulses and the analog input of the electronic key 3. The output of the input driver 2 pulses are connected to the inputs of the driver 4 impulse | Ca and the selector 5 frequencies. The control input of the electronic key 3 is connected to the output of the driver 4 of the pulse, and the output of the electronic key 3 is connected to the input of the peak detector 6.

Output peak detector 6 connect

with the analog input of the analog-digital converter 7; the first output of the analog-digital converter 7 is connected to the control input of the driver 4 pulses and the installed input of the peak detector 6.

The frequency selector 5 has n outputs in accordance with the expected number of different frequencies of the input signal. Each of these outputs is connected to one of the inputs of the element or 8.

The output of the element OR 8 is connected to the logical input of the analog-digital converter 7.

Digital outputs are analog-to-digital. The converter 7 is output device 9.

Frequency selector 5 (Fig. 3) is made in the form of p-channels, each of which, except the first and last, consists of a series-connected element 10, a threshold element 11, a second element 12 and a trigger 13, with the first input of the first element And 10 is connected to the input of the selector 5 frequencies, the output of the first element And 10 - with the second input of the second element And 12, the first trigger code - with the second input of the threshold element 11, the second output of the trigger 13 of this

0

five

0

0

five

0

five

0

five

the channel is connected to the second input of the first element And 10 of the subsequent channel, the output of the second element And 12 - with the output of the frequency selector 5, the second inputs of the trigger of all channels are combined and connected to the bus Reset, the first channel contains the threshold element; 11, the first input of which is connected with the input of the selector, element 12 and trigger 13 when the remaining connections are identical, the last channel contains the first element 10 and threshold element 11 and the second element 12 when the remaining connections are identical.

As can be seen from FIG. 3 schemes, the frequency selector consists of p of the same type links. The exception is the first link, in which there is no matching circuit at the input, and the last link, in which there is no trigger 13. Threshold element 11 (for example, a COOL relay) of each link is configured by setting the time of the RC chain for a specific output signal duration. .

As can be seen from the timing diagram shown in FIG. 4, the duration of the signal of the threshold element 11 of the first link must overlap the period of the frequency fJ of the sequence of frequencies inputted to the input of the frequency selector, but not exceed the period of the frequency f i. The duration of the signal of the second link UShP relay should cover the period of the frequency fj, but not exceed the period of the frequency fjv, etc.

With the appearance of the first impulse of higher frequency at the output of the AND 12 element, an impulse appears, which flips the trigger 13 into the opposite state, prohibiting the operation of the PPM relay 11 and opening the AND 10 element.

Thus, a single pulse appears at the output of each link at the time of the occurrence of the next frequency packet in the input signal. ; The measuring transducer works as follows.

A sinusoidal input signal (Fig. 2a) is converted by the input pulse shaper 2 into a series of square pulses (Fig. 2b).

As such a former

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When you change the frequency of the input

signal at the corresponding output

five,

frequency selector 5, a single impulse (Fig. 2c) appears at one of the inputs of the element OR 8. The output impulse of the element OR 8 fits with the starting impulse of the analog-digital converter 7 (Fig. 2d).

On this signal, the analog-to-digital converter 7 converts the analog signal of the peak detector 6 into a digital code. Upon completion of the conversion, the End of Conversion signal (Fig. 2e) returns to its initial state the peak detector 6 and prepares the pulse shaper 4 for the next operation cycle.

A shaper 4 shshulsa with the arrival of successive rectangular pulses at its input produces a single direct-impulse pulse, the duration of which is equal to the period of the input pulses (Fig. 2f). This pulse, which enters the logical input of the electronic key 3, opens it and passes the analog sinusoidal signal from the input bus 1 to the input of the peak detector 6 during one period (Fig. 2g).

Peak detector 6 rectifies and stores the amplitude value of the input signal. With the arrival of the signal. The end of the conversion from the analog-digital converter 7, the peak detector 6 returns to its original state, preparing for a new operating cycle.

Invention Formula

Claims (2)

1. A measuring transducer containing an input pulse shaper, whose input is the input of the device, a frequency selector and an OR element, characterized in that, in order to expand the range of operating frequencies, an electronic key, peak detector, driver pulse and analog-to-digital converter, the analog input of which is connected to the output of the peak detector, the logic input is connected to the output of the element OR the digital outputs are connected to the output buses of the measuring converter, and the first output is connected to the control input of the driver pulse and the installation input of the peak detector, the input of which is connected to the output of the electronic key, the control input of which is connected to the output of the pulse former, and the input is connected to the input of the input pulse former, the output of which is connected to the input of the pulse former and the selector of the frequency selector, the second input of which is connected with bus Reset, n outputs of which are connected respectively to the n inputs of the element OR. five 0 five 0 five 0 five 0 2. The converter according to claim 1, characterized in that the frequency selector is made in the form of n channels, each of which except the first and last, consists of a series-connected element AND, a threshold element, a second element And and a trigger, with the first input of the first element AND connected to the input of the frequency selector, the output of the first element I - with the second input of the second element I, the first output of the trigger - with the second input of the threshold element, the second output of the trigger of the first channel connected to the second input of the first element I of the subsequent channel, output g of the second element I - with the output of the frequency selector, the second inputs of the flip-flops of all channels are combined and connected to the bus Reset, the first channel contains a threshold element, the first input of which is connected to the input of the frequency selector, the element I and the trigger connected in series, the first input the threshold element is connected to the second input of the AND element, its second input is connected to the first output of the trigger, the second output of which is connected to the second input of the first AND element of the second channel, and the output of the AND element of the first channel to the output of the frequency selector, The first channel consists of the first AND element in series, the threshold element and the second element And, the output of which is connected to the output of the frequency selector, its second input - with the output of the first element And, the first input of which is connected to the input of the frequency selector, and its second input - the second exit trig "- p .-.". ..-. “. ch Hera n-1 channel. cdl / shne rn-jn-j- -jnjnjonjTJumrL npfo5fiojo & fff time e 1 well Phi $ .2 and C (f5.h) FIG. four IT