SU436446A1 - DEVICE FOR DIVIDING FREQUENCY WITH A FRIENDLY COEFFICIENT - Google Patents

Description

one

The invention relates to the field of automation and computer technology and can be used in the development of communication search equipment.

A device for dividing a frequency with a fractional coefficient is known, which contains a decade frequency divider with a notational dividing coefficient, performed on counting decades, coefficient selection matrices, a counter overload fixing circuit, and a presetting pulse generator, tenth tenth and hundredths of the division factor, coefficient shift schemes and match schemes.

In order to increase speed and evenly distribute non-time counting by dividing cycles, the input of the decade is one hundredth of the division factor connected to the ten-decade output of the tenth division factor, the input of which is connected to the output of the ten-day frequency divider with a constant division factor, the tenth output and hundredths of the division coefficient through additionally established logic circuits are connected to the coefficient shift circuits, a decade of divider units with constant th coefficient dividing circuit is connected through a shift coefficients per unit of yield shift circuit coefficients decade tenths coefficient lobes and between the units decade and subsequent decades frequency divider with constant division kveffitsieitom included donolnitelna logic nerenosa.

FIG. 1 shows the scheme of the proposed device; in fig. 2, a is a block diagram of a decade; in fig. 2,6 - its stress plots; on

FIG. 2, c — an embodiment of implementing coefficient shifts by one to obtain the necessary values in a fractional bit; in fig. 2, g - the table of the decade. The proposed device contains counting decades 1, 2 and 3, decades 4 and 5 tenths and hundredths of the division factor, coefficients matrixes 6, 7 and 8, coincidence schemes 9 and 10, coefficient shift scheme 11 by one, shift schemes 12 and 13 coefficients, a fixation circuit 14 for filling the counter, a presetter shaper 15, and a transfer logic 16.

The proposed device consists of two

parts: a decadal frequency divider with a constant division factor that implements integer coefficients, which include devices 1, 2, 3, 6, 7, 8, 14 and 15, and a scheme that allows a specific program in

during the work of the divider, change its coefficient

The unit per unit, where devices 4, 5, 9, 10, 11, 12, 13 and 16 are included.

In order to obtain a shift of the coefficients by one to the inputs of the matrix 6 for the selection of coefficients, the corresponding And outputs of the circuit 11 are connected (Fig. 3). Commands for setting integer coefficients from the control knobs are in this case supplied to the inputs of this circuit.

If, for example, a zero potential is applied to the input “3, b, then this command can appear at the output of“ 3, and or “4, and depending on which command is present at the input“ e - “O or“ 1. At the moment of submission, at the input "e command" O this command appears at the output "3, and, and when giving the command" 1 - at the output "4, and. The same thing happens when commands are sent to the inputs "g, and the inputs" 3 are not used.

The program for shifting the coefficients by one during operation of the divider is generated using the circuit 4, triggered by the output pulses of the integer DPCD, and the adjustable coincidence circuit 9.

To obtain the necessary programs shown in FIG. 2, c, an adjustable coincidence circuit is used (Fig. 2 d).

Depending on the number of tenths, the switch (Fig. 2, e) is set to the appropriate position, and the signal from its output is fed to the input of the "shift circuit" (Fig. 3).

Consider the implementation of coefficients with two fractional bits.

"

/ Zi

.

ten

100

To obtain L / sr it is necessary to calculate the coefficient N-i- 2 times, and the coefficient

N- 100- “2 times, i.e. in one hundred counting cycles

n + l

it is necessary to change the coefficient with

t

On L - | - (To change the program of tenths

from rti to П1 + 1). For the realization of hundredths, the corresponding decade 5 is introduced, which counts down the ten counting cycles of the integer DPCD, since it starts from the decade 4 decimal places. In order to obtain shifts in the program of tenths when obtaining a bit of hundredths, scheme 12 is introduced, which switches the program of tenths from ni to ni + 1 according to commands from scheme 13 or 10, depending on the number of subsequent fractional bits.

The schematic diagram for the shift of the program of the tenth is the same as for the shift of the program of unit coefficients (Fig. 3), but it is included in a slightly different way.

In this case, the instructions for setting tenths of the control knobs are given to the input, and the outputs of circuit 9 (Fig. 1) of forming the program of the tenth fractions are connected to the corresponding inputs of the W (Fig. 3) shifting circuit.

The input “e” receives a program of hundredths, 5, generated by circuits 5 and 10, which are identical to the corresponding circuits 4 and 9 tenths. The inputs "g of the shift circuit are combined through the" OR circuit, the output signal from it is fed to the input of the "shift circuit 11 of 0 coefficients per unit.

The operation of the circuit 12 in the shift mode of the program of tenths is as follows.

Suppose the command “About to input 5” 3 is given, which means setting the coefficient

3 L - {. However, depending on the level

input "e to outputs" and can connect

34

0 program or (output "3, g or

at the output of “4, d), i.e. the program of hundredths in the input“ e, it is possible to shift the coefficients by one into tenths, which makes it possible to obtain hundredths in the coefficient

.

The same is true when obtaining the discharge of thousand, etc. When obtaining coefficients with fractions,

0 when the unit is set to nine in the decade of units, in terms of division cycles, it is necessary to obtain division factors in the first decade equal to ten, which is impossible, since the unit decade can realize coefficients from O to 9 in this construction of the circuit, therefore instead of setting 10, installation is made 0. To avoid errors in this situation, an additional transfer logic 16 is introduced, which in the case where the number

0 units is set to 9 and in order to obtain fractionality it is necessary to increase the factor by one in certain counting cycles, i.e., to get 10, crosses out one output impulse of a decade of units, while its setting is made in "O, which ultimately corresponds to the count of ten these pulses. Circuit 16 may consist of a trigger with corresponding matching circuits.

Subject invention

A device for dividing the frequency with a fractional variable coefficient, containing a decade frequency divider with a constant division factor, performed on counting decades, coefficient selection matrices, counter filling fixation scheme and preinstallation pulse former, decade of tenths and hundredths of the division factor, coefficient shift schemes and joint schemes, characterized in that, in order to increase the speed of the device and to evenly distribute the variable count over the division cycles, the input is decad dividing coefficient hundredths lobes connected to the output decade tenths dividing ratio, whose input is connected to the output pulse shaper presetter decadic frequency divider with constant division ratio, outputs decades tenths and hundredths fraction dividing ratio set via the further logic circuit are connected to

the coefficient shift schemes, the decade of a divider unit with a constant division factor are connected through the coefficient shift circuit by one unit with the output of the tende factor coefficient shift scheme with the tenth fraction of the coefficient, and between the decade of units and the subsequent decade a frequency divider with a constant division factor is included.