SU1109893A1 - One-shot multivibrator - Google Patents

Abstract

MULTI-VIBRATOR, containing the first trigger, second trigger, counter, synchronizer, control bus, characterized in that, in order to increase the stability of the output pulse duration, the multivibrator control bus is connected to the counting input of the first trigger, the installation input in O which is connected to the inverse output of the second trigger, the setup input in 1 of which is connected to the inverse output of the first trigger, and the setup input in O of the second trigger is connected to the inverse output of the last digit of the counter, direct output to orogo trigger input is connected to the installation in the ON counter and the control input of the synchronizer, the output of which is connected to the counting input of the counter. (L

Description

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This invention relates to automation and computing, and can be used in time slices by time selectors.

A known multivibrator is known, containing an RS flip-flop on two NAND elements, a delay element whose output is connected to the RS flip-flop S input, and an inverter input to the RS flip-flop 0 output, the RS flip-flop input is control input of the multivibrator 1.

The disadvantages of this standby multivibrator are low stability, a strong dependence of the duration of the output pulses on temperature, the semi-angle of small pulse durations, the dependence of the output signal on the duration of the input signal.

The closest in technical essence to the present invention is a standby multivibrator comprising a first trigger, a second trigger, a counter, a synchronizer, a control bus, two AND-NES elements, the synchronizer output being connected to the first input of the first II-NEA element, the output of which is connected with a counting meter input, a direct output of the second digit of the meter is connected to the first input of the second NAND element. and a direct output of the third digit of the meter is connected to the counting input of the first trigger, the inverse output of which is connected to the counting input v of the first trigger, the inverse output of the latter is connected to the second input of the second NAND element, the output of the second NAND element is connected to the second input of the first NAND element, the installation inputs in O of the counter and both triggers are connected to the control bus of the device 2.

A disadvantage of the known device is the low stability of the pulse duration.

The aim of the invention is to increase the stability of the duration of the output pulses.

The goal is achieved by the fact that in the waiting multivibrator containing the first trigger, the second trigger, the counter, the synchronizer, the control bus, the multivibrator control bus is connected to the counting input of the first trigger, the input

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with the inverse output of the second trigger, the installation input into 1 is connected to the inverse output of the first trigger, and the installation input to the second trigger O is connected to the inverse output of the last digit of the counter, the forward output of the second trigger connects to the installation input of the counter O and the control input sync .former, the output of which is connected to the counting input of the counter.

FIG. 1 shows a functional diagram of the proposed device; in fig. 2 - time diagrams.

The proposed device contains the first trigger 1, BTopoit trigger (RS trigger) 2, counter 3, synchronizer 4, the synchronizer control input 5 and the multivibrator control bus 6.

The output of the synchronizer 4 is connected to the counting input (T) of the counter 3. The output (Qn) of the counter 3 is connected to the installation input to O (R) of the second trigger 2 (RS-type), the output of which is connected to the control input 5 of the synchronizer 4 and the installation input in O (R) of the counter 3. The inverse output of the second trigger 2 is connected to the input of the installation in O (R) of the first trigger 1 with a counting output, the inverse output of which is connected to the input of the installation in O (S) of the second trigger 2, and the control 6 is connected with a counting input (T) of the first trigger 1.

Waiting multivibrator works as follows.

In the initial state, the inverse outputs of the first trigger 1 and the RS-trigger 2, QVI - the output of the counter 3 is in the unit state, and the direct output of the RS-trigger 2 is in the zero state, which in turn keeps it in the zero state counter 3 and the control input of the synchronizer 4, thereby prohibiting the excitation of oscillations in it.

Let a trigger pulse be sent to the control bus of the waiting multivibrator at time t (Fig. 2a). As a result of the impact of the front of this pulse on the counting input of the trigger 1, a state of logical zero is established at its inverse output (Fig. 26). The zero potential from the inverse output of the trigger 1paways on the S-input of the RS-griger 2i and persku.byyuet it in such a way that zero is established at its inverse output, and the unit potentials on the direct output (fig. 2c, d). The zero potential from the inverse output of RS-flip-flop 2 affects the R-input of flip-flop 1 and returns the latter to the initial state. A unit potential is established at its inverse output (Fig. 26). The instant of the occurrence of a single potential at the direct output of the RS-flip-flop 2 (instant t in Fig. 2) at the control input of the synchronizer 4 is set to the resolving unit potential and the synchronizer begins to generate a pulse Signal whose frequency stability is determined by the parameters of the quartz resonator (fig, 2d). From the synchronizer output, a pulse signal is sent to the counting input of the counter 3, which counts the pulses up to the time point t, when the output of the counter 3 has a zero potential (Fig. 2e), which affects the R input of the RS flip-flop 2, switches it. As a result, a zero potential is established at the forward output of the RS flip-flop 2, and a single potential is established at the inverse output. Thus, starting from the moment tg, the device is reset, if at the time t an interference impulse impinges on the device input, the device will not malfunction, since starting from time tjr determined by the switching time the trigger until time t / c trigger 1 on the inverse output will be held in a single state of influence on its R-input by a zero potential from the inverse output of the RS-flip-flop 2, When exposed in time to fe on a control multiple ibratora pulse of long duration (Figure 2a) 1 ustanovits trigger on the rising edge of the pulse in the zero state at the output of the inverse. As a result, the RS flip-flop 2 also becomes the inverse output to the zero state, and the direct one. The zero state of the inverse output of the RS flip-flop 2 is bu-. It will support trigger 1 on the inverse output in the unit state in which it is set at time t. determined by the switching time of this trigger when its pre-zero potential is applied to its R input. In this state, the standby multivibrator will be up to the time point tg, when the entire volume is filled in the counter 3 and on its F, - output, there is a zero potential setting the standby multi-. vibrator in its original state. If the duration of the generated output pulse of the multivibrator is less than the duration of the trigger pulse, i.e. setting the standby multivibrator to its initial state will occur before the end of the input triggering pulse, then the new multivibrator will not turn on until the next triggering pulse arrives, since the proposed standby multivibrator can only be started after the end of the cyclic formation of the output pulse at the moment of the leading edge of the triggering pulse . The output signal is taken from the direct and inverse outputs of the RS flip-flop.

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Claims (1)

A LOOKING MULTIVIBRATOR, comprising a first trigger, a second trigger, a counter, a synchronizer, a control bus, characterized in that, in order to increase the stability of the duration of the output pulses, the multivibrator control bus is connected to the counting input of the first trigger, the input of which is connected to 0 the inverse output of the second trigger, the input of which 1 is connected to the inverse output of the first trigger, and the input of 0 to the second trigger is connected to the inverse output of the last digit of the counter, direct output of the second iggera connected to the input of the counter to 0 and setting the control input of the synchronizer, the output of which is connected to the counting input of the counter. figure 1 1 -. 1109893 2