SU1734192A1 - Controlled multivibrator - Google Patents

Abstract

The invention relates to a pulse technique. The aim of the invention is to reduce the recovery time. The multivibrator contains three transistors, two capacitors, four resistors. The goal is achieved by the introduction of an electronic key. The electronic key can be made on two transistors, two resistors and a zener diode, 1 hp. f-ly, 1 ill.

Description

The invention relates to a pulse technique and can be used in various automation devices, for example, in a number of pulse generators.

The purpose of the invention is to reduce the recovery time of a controlled multivibrator.

The drawing shows a schematic diagram of the proposed controlled multivibrator.

The controlled multivibrator contains tri-polar transistors 1–3 of the same conductivity, two bipolar transistors 4 and 5 with a conductivity opposite to transistors 1–3, six resistors 6–11, Zener diode 12, time setting capacitors 13 and 14, bus 15 of the power supply and the common bus 16, the base of the transistor 3 being the control input 17 of the controlled multivibrator, the emitters of the transistors 2 and 3 are connected to the bus 16, and the collector of the transistor 3 is connected to the emitter of the transistor 1 and

the output of the resistor 10, while the collectors and bases of the transistors 1 and 2 are connected through the corresponding resistors 6-9 to the bus 15, and the base of the transistor 1 is connected to the first plate of the capacitor 13, the second plate of which is connected to the collector of the transistor 2, the base of which is connected to the first plate the capacitor 14, the second plate of which is connected to the collector of the transistor 1, the second terminal of the resistor 10 is connected to the base of the transistor 4, the collector of which is connected through the resistor 11 to the bus 16 and through the Zener diode 12c to the base of the transistor 5, transit emitters The sources 4 and 5 are connected to the bus 15, and the collector of the transistor 5 is connected to the base of the transistor 1, the combination of elements 4, 5, 10, 11 and 12 and the connections between them form an electronic switch 18.

The operation of the controlled multivibrator in the established self-oscillatory mode (in which the transistor 3 is open and saturated) is no different from the operation

(L

WITH

v sob

with N:

controlled prototype multivibrator, since the electronic switch 18 is closed due to the fact that the transistor 4 is open and saturated and the voltage on Zener diode 12 is less than its stabilization voltage, the current through Zener diode 12, which is the base current of transistor 5, is absent and the transistor 5 is closed.

When the transistor 3 is closed, transistor 1 also closes, and transistor 2 opens and becomes saturated. At the same time, the electronic switch 18 opens, as the transistor 4 closes and the Zener diode 12 punches, allowing the base current of the transistor 5 to flow through the circuit: bus 16 - resistor 11 - zener diode 12 - base of transistor 5 - emitter of transistor 5 - bus 15. Transistor 5 opens and becomes saturated shunt the resistor 7 in the recharge circuit of the capacitor 13 and the resistor 6 in the charge circuit of the capacitor 14. In this case, the capacitor 13, unlike the prototype, is recharged as a circuit: bus 16 - emitter of transistor 2 - collector of transistor 2 - second capacitor plate and 13 - the first capacitor plate 13 - resistor 7 - bus 15 and the circuit: bus 16 - emitter of transistor 2 - collector of transistor 2 - second plate of capacitor 13 - first plate of capacitor 13 - collector of transistor 5 - emitter of transistor 5 - bus 15, which leads to an increase in current recharging capacitor 13 compared with the prototype. At the same time, the capacitor 14, unlike the prototype, is charged as a circuit: bus 16 — emitter of transistor 2 — base of transistor 2 — first plate of capacitor 14 — second plate of capacitor 14 — resistor 6 — bus 15, and along the circuit: bus 16 - emitter of transistor 2; base of transistor 2 - first plate of capacitor 14 - second plate of capacitor 14 - collector of transistor 1 - base of transistor 1 - collector of transistor 1 - collector of transistor 5 - emitter of transistor 5 - bus 15, which leads to an increase in charging current yes capacitor 14 compared to the prototype.

Consequently, in comparison with the prototype, the recharging time of the capacitor 13 and the charging time of the capacitor 14, which determine the recovery time of the controlled multivibrator, are reduced.

Thus, the proposed technical solution in comparison with the prototype has a reduced recovery time due to the automatic reduction of the constant time of the charging circuit of both the time of the driving capacitors when the third transistor is closed.

Claims (2)

1. A controlled multivibrator containing first, second and third transistors, first and second capacitors, first to fourth resistors, the collectors of the first and second transistors being connected via the first and second resistors to the power supply bus and the bases of the first and second transistors respectively the third and fourth resistors are connected to the power supply bus, the first capacitor is connected between the collector of the first and the base of the second transistors, the second capacitor is connected between the collector of the second and At the first transistor, the emitters of the second and third transistors are connected to a common bus, the collector of the third transistor is connected to the emitter of the first transistor, the base of the third transistor is a device control input, characterized in that an electronic key is inserted into it, and the signal inputs of the electronic switch are connected to the terminals of the third resistor, the control input of the switch is connected to the collector of the third transistor. 2. Multivibrator pop. 1, which differs from the fact that the electronic key contains fourth and fifth transistors, fifth and sixth resistors, a zener diode, the emitter of the fourth transistor is connected to the power supply bus, the collector is connected via the fifth resistor the common bus and the cathode of the zener, the anode of which is connected to the base of the fifth transistor, the collector and the emitter of which are the signal inputs of the electronic key, the control input of which is connected through the sixth resistor to the base of the fourth transistor.