SU1626339A1 - One-shot multivibrator - Google Patents

Abstract

The invention relates to a pulse technique. The goal is to increase the stability of the duration of the formed pulse. The goal is achieved by the introduction of a standby multivibrator of a generator of 7 rectangular pulses, element 8, inverter 9 and keys 10-12. The standby multivibrator also contains an RS flip-flop 1, the time specifying a capacitor 2, a dongle made on a transistor 3, a current source 4, reference resistor 5, comparator 6. 1 Il.

Description

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The invention relates to a pulse technique and can be used in automation and computer systems.

The purpose of the invention is to increase the stability of the duration of the formed pulses.

The drawing is a schematic diagram of the waiting multivibrator.

The multivibrator contains an RS-flip-flop 1, the S-input of which is connected to the input bus of the waiting multivibrator, the time specifying the capacitor 2. a discharge key made on transistor 3, the base of which is connected to the first output of the trigger 1, the emitter - to the common bus, the collector - with the first terminal, the time of the reference capacitor 2, the second terminal of which is connected to the common busbar source 4 of the charging current and the driver of the capacitor 2 and creating a reference voltage on the supporting carriage 5, a comparator G, the first input of which is connected to the first terminal of the reference cylinder - glor 5. The second input of the resistor 5 is connected to the common bus, the output of the comparator 6 is connected to the R-input of the trigger 1, the generator 7 of rectangular pulses, the element I / I 8 and

inverter

connected in series the first key 10, the information input of which is connected to the collector of transistor 3, the control input — to the output of the element AND 8; a second key 11, whose information input is connected to the current source 4 and the output of the first key 10, the control input — to the output of the inverter 9, and the output is with the first input of the comparator 6 and the first output of the reference resistor 5, the third key 12 whose information input is connected to the first time output — driver capacitor 2, the output to the second input of the comparator b, and the control input to the output of the invert ora 9, the second output of the trigger 1 is connected to the second input of the element And 8.

Multivibrator works as follows.

In the initial state of the device, trigger 1 occupies a position at which a high logic level signal acts on its first output, and a low level on the second output. In this case, the transistor 3 is saturated and the voltage on the plates of the time capacitor 2 becomes equal to the saturation voltage UH of the transistor 3. A high logic level signal is output at the output of the And 8 element, and a low level at the output of the inverter 9. When this key 10 is open and the current source 4 current flows through the open transistor 3. The keys 11 and 12 are closed. When a generated pulse is applied to the first input of a tripa 1, it moves to a new position, at which a low level signal acts on its first output and a high signal on the second output. Wherein

the transistor 3 goes to the closed state. At the output of element And 8, the CHI of high and low logic levels alternates with a frequency determined by the generator frequency 7 rectangular

0 pulses. Alternating signals of logic levels at the outputs of the element And 8 and inverter 9 lead to alternate opening of keys 10-12. Such alternation of logical levels leads to

5 switching the current of the current source 4, respectively, to the charge of the capacitor 2 and creating a reference voltage on the reference resistor 5 (voltage drop across the resistor 5) Key 12 connects the first terminal

0 of the capacitor 2 to the second descent of the comparator 6 when there is a reference voltage at its first input, formed on the resistor 5. At the same time, the voltage on the capacitor 2 increases in discrete steps. The duration of the increase is determined by the duration of the control pulse key 10, the capacitance of the capacitor 2 and the current of the current source 4 When the voltage Uj reaches the time of the incoming capacitor 2,

0 equal to the reference Do (U - U0 ISop Rs), the comparator 6 is triggered and a pulse is generated at its output, which returns trigger 1 to the initial state

Claims (1)

Thus, in the proposed device, the current of the same current source alternately ensures charging the capacitor and creating a reference voltage on the reference resistor. Switching on the keys does not affect the current source voltage. This ensures an increase in the stability of the pulse duration . Claims of the Invention Suspended multivibrator containing 5 RS-flip-flop, the S-input of which is connected to the input bus of the waiting multivibrator, the time setting the capacitor, in parallel with which the bit switch is connected, the base of which is connected to the first output 0 trigger and emitter - to the common bus of the current source reference resistor - one of the terminals of which is connected to the first input of the comparator, and the other - to the common bus, the output of the comparator is connected to the R input 5 flip-flops, characterized in that, in order to increase the stability of the duration of the pulse being formed, a square pulse generator, an AND element and an inverter connected in series are inserted into it, first, third, third keys, 5 16263396 the information input of the first key, the co-input of the third key is connected to the first terminal; the master capacitor, the control input, from the output, the output, to the second input of the comparator; the house of the element is And, the output is with the output of the source control inputs of the second and third current stallion and the information input5 whose are connected to the output of the inverter, the second the second key, the output of which is connected to the trigger output is connected to the second input the first input of the comparator, the information element I.