SU705652A1 - Square pulse generator - Google Patents

Description

(54) GENERATOR OF RECTANGULAR PULSES

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The invention relates to a pulse technique and can be used in automation and remote control devices.

Generators of rectangular pulses are known (1 and (2.

One of the known generators contains resistive amplifiers with a delay line in the feedback circuit 1.

The disadvantage of this generator lies in its low noise immunity.

The closest technical solution to the invention is a square-wave pulse generator comprising a trigger, a delay line, two NAND elements and inverters, with the delay line taps being connected to the inputs of the first 2J inverter.

However, this generator has a low noise immunity.

The purpose of the invention is to increase the noise immunity of the generator.

To do this, in the generator of rectangular pulses, containing a trigger, a delay line, two IS-NOT elements and inverters, with the delay line taps connected to the inputs of the first inverter, the inverters are connected between the inputs of the second element

and -NON and taps of the delay line connected to the trigger output, the input whose inputs are connected to the outputs of the NAND elements.

The drawing shows a functional electrical circuit of the generator.

It contains a trigger 1, the output of which is connected to the input of delay line 2. OgvoSh delay line 2 is connected to the inputs of the element AND-NOT 3 and the inputs of inverters 4, 5, 6, the outputs of which are connected to the inputs of the second element AND-NOT 7. The outputs of the elements AND - NO 3 and 7 are associated respectively with the zero and single inputs of trigger 1.

The square pulse generator operates as follows.

Consider the steady state oscillation mode. Let a zero level potential be set at the output of trigger I, after the delay time of the entire delay line 2 expires, the zero potential will be established at all of its branches.

If there is a zero potential at all taps of the delay line 2 at the outputs of inverters 4, 5, 6, the voltage in the medium voltage corresponds to the potential of a high level (unit level) that goes to the inputs of the AND-NE element 7, which (normalizes the pulse the duration of which is equal to the delay time of one 5 | vein of delay line 2. The output impulse of the element AND - NOT 7 flips trigger 1 into one state (high level). The potential of the high level from the output of trigger I is equal to the delay time of the entire line 2, set on everything its taps to the data inputs of AND-NO element 3, whose output pulse is generated, sets the flip-flop I to zero (low level), and the whole cycle is repeated.

If the input delay 2 delayed a series of serials, then at the taps of line 2 there is a potential of different level in the vehicle, and at the NAND 7 element (or the NAND element 3, depending on which element worked before the failure) will not happen. After a time equal to the delay time of the entire line 2, after the last pulse of the fault, the potentials of the same level are again established at the taps of line 2. These potentials are fed to the inputs of the element AND-HE 7 or the element AND-HE 3, which forms the output pulse 3ahycKa of the trigger 1.

In this way, the former frequency of the oscillator oscillator will be set. i

Claims (2)

1. Yakovlev V.N. Impulse generators on transistors. Kiev, “Technique, 1968, p. 353, fig. 178. 2. USSR author's certificate No. 436433, H 03 K 3/64, 07.07.71 (prototype).