SU1659972A1 - Pulse generator - Google Patents

Abstract

The invention relates to devices for increasing the average accuracy of the period of the output signal of a pulse generator and can be used in stand-alone automation devices for generating time stamps. The purpose of the invention is achieved by introducing 2 pulse trains, a first frequency divider 3, a pulse subtraction unit 4, a second frequency divider 5 into the generator device, and new functional connections. In addition, the device contains a reference generator 1, a temperature sensor 6 and a functional converter 7 temperature - code. The increase in the average accuracy of the output signal period is achieved by increasing the number of trimming increments and decreasing the average trimming increment, which is achieved by correcting the period of the device output signal only in every nth period, unlike the prototype device, where such adjustment is made for each period of the output signal. 3 il.

Description

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The invention relates to a pulse technique and can be used to form time stamps in automation devices.

The purpose of the invention is to increase the average accuracy of the period of the output signal of the pulse generator.

FIG. 1 shows a functional diagram of the pulse generator; in fig. 2 and 3 are embodiments of a pulse burst generator and a pulse subtraction unit, respectively.

The device comprises a reference generator 1, a generator of 2 bursts of pulses, a first frequency divider 3, a pulse subtraction unit 4, a second frequency divider 5, a thermal sensor 6, and a functional converter 7 a temperature code.

The output of the sensor 6 is connected to the input of the functional converter 7 temperature — a code whose output is connected to the control input of the generator 2 of a packet of pulses whose output is connected to the input of the first frequency divider 3, the output of which is connected to the control input of the pulse readout unit 4 connected to the input of the second frequency divider 5, the output of which is the output bus of the device. The output of the reference generator 1 is connected to the clock inputs of the generator 2 of a burst of pulses and the pulse subtraction unit 4.

The generator 2 packs of pulses (Fig. 2) contains a frequency divider 8, a controlled frequency divider 9, an RS flip-flop 10 and an And 11 element.

The clock input of the generator 2 packs of pulses is connected to the counting inputs of the frequency divider 8 and the controlled frequency divider 9, as well as to the first input of the And 11 element, the output of which is the generator output 2 packs of pulses, the control input of which is connected to the information input of the controlled divider 9 frequency, the recording input of which is connected to the output of the frequency divider 8 and to the S input of the RS trigger 10. The output of the controlled frequency divider 9 is connected to the R input of the RS flip-flop 10 whose output is connected to the second input of the And 11 element.

The pulse subtraction unit 4 (Fig. 3) contains the first and second D-flip-flops 12 and 13 and the element OR 14.

The clock and control inputs of the pulse subtraction unit 4 are connected respectively to the C-inputs of the first and second D-flip-flops 12 and 13. The D-input of the first D-flip-flop 12 and the R-input of the second D-flip-flop 13 are connected to buses with level signals 1 and Oh accordingly. The R input of the first D flip-flop 12 is connected to the output of the second D flip-flop 13 and to the first input of the OR 14 element, the output of which is the output of the pulse subtraction unit 4. Second entrance

element OR 14 is connected to the C-input of the second D-flip-flop 13, the D-input of which is connected to the output of the first D-flip-flop 12.

The device works as follows.

0 A reference generator 1 (for example, a quartz crystal) generates signals with a frequency f0, depending on temperature. The temperature of the reference generator 1 is measured by the thermal sensor of the biv functional converter 7 temperature — the code is converted into a binary code N, depending on temperature T. The functional converter 7 is temperature — the code can be executed, for example, in series

0 a digital signal meter parameter of the temperature sensor 6 (e.g., frequency) determining the temperature, and a ROM storing the desired N (T) dependence.

The binary code N (, T) is fed to the control input of the generator 2 packs of pulses, at the output of which for every M0 clock pulses of the reference generator 1 specified by frequency divider 8, a pack of pulses is formed, the number of pulses of which is M (T)

0 is determined by frequency divider 9. The output of the pulse burst generator 2 is divided by frequency in the first divider 3 frequencies by NI times.

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5 pulses of the first divider 3 frequencies in block 4 of the pulse subtraction blocks the passage of clock pulses to its output, one for each output pulse of the first divider 3 frequencies

0 Blocking is carried out by forming with the help of D-flip-flops 12, 13 on the first input of the element OR 14, fulfilling the role of a prohibition element, which prohibits (single) signal with a duration of

5 one clock interval, formed with the arrival of each input pulse to the control input of unit 4. As a result, the frequency of the thinned pulse sequence at the output of the pulse subtraction unit 4

0 is equal to the frequency difference between the signals of the reference oscillator 1 and the first divider 3 frequencies.

The output signal of the pulse subtraction unit 4 is fed to the input of the second frequency divider 5, where it is divided by frequency N2 times, forming

5 thus the output signal of the device with the frequency

f fo (1-N (T) / N0kNi) / N2 From the formula it can be seen that the number of adjustment increments is determined by the maximum value N (T), and the relative adjustment step is 1 / N0; Ni and with an appropriate choice of the work can be performed sufficiently small, bounded below in size by the stability characteristics of blocks 1, 6 and 7.

It also follows from the above formula that in the proposed device, not every period at the output of the device can be adjusted for duration, but only every n-th period, where n N0vNi / N2. In this case, in a thinning sequence, clock pulses are suppressed n times less often than is required to adjust the duration of each cycle of operation of the second frequency divider 5. As a result, an increase in the average accuracy of the output signal period is achieved as compared with the prototype device by reducing the average magnitude of the tuning discrete, increasing the number N of samples and reproducing the temperature converter in the functional converter 7 — the code of the corresponding dependence M (T) providing compensation in accordance with the the formula of temperature drift of the frequency of the reference generator 1.

Claims (1)

Claims Pulse Generator Containing reference generator and series-connected thermal sensor and functional temperature transducer — a code characterized in that, in order to increase the average accuracy of the output signal period, a controllable pulse generator, first and second frequency dividers, and a pulse subtraction unit are entered into it, the output of the functional temperature transducer is the code is connected to the control input of the pulse burst generator, the output of which is connected to the input of the first frequency divider, the output of which is connected to the control input of the block you read pulse, the output of which is connected to the input the second frequency divider, the output of which is the output bus of the device, the output of the reference oscillator is connected to the clock inputs of the pulse train generator and the pulse subtraction unit.