SU728217A1 - Single-shot multivibrator - Google Patents

Description

The invention relates to a pulse technique and can be used for the formation of rectangular pulses and in device delay devices. A one-shot emitter coupling is known, which contains input and output transistors with a base-capacitor coupling ij. The known one-shot has insufficiently short recovery time. The purpose of the invention is to reduce the recovery time. To achieve this, a thyristor, a diode and a differentiation node are introduced into an emitter-coupled single vibrator with an emitter-coupled input-output transistor with a collector-base-capacitive coupling. The anode and the cathode of the thyristor are connected to the input transistor collector and the power supply bus a thyristor cathode in the opposite direction, and the anode and cathode of the diode are connected to the output terminals of the differentiation unit, one of the input terminals of which is connected to the bus through a resistor Ethan, and the other - with the output transistor collector. FIG. 1 shows the basic electrical circuit of the device; in fig. 2 is a diagram describing the duration of the stages of the recovery of the known 1 and the proposed P single vibrators. The mono-vibration includes transistors 1 and 2, capacitor 3, resistors 4-9, thyristor 10, diode 11, and differentiation unit 12. The one-shot works as follows. In the initial state, the voltage between the electrodes of the thyristor Yu is approximately zero, the resistance between its cathode and anode is large and does not affect the operation of the device. After supplying the trigger pulse and tipping the circuit, a negative pulse appearing at the output of the spreading node when the transistor 2 is closed,

It is shocked by diode 11; the control electrode – cathode of the thyristor 10 is protected against the effects of reverse voltage pulses. As the capacitor 3 is discharged, the forward voltage between the anodes and the cathode of the thyristor 10 increases. As soon as the one-shot exposure time ends, the transistor 2 opens, a positive impulse opens at the output of the differentiation unit 12, the thyristor 10 opens, and its resistance between the cathode and the anode becomes small. The thyristor 10 will be open until the charging current of the capacitor 3 becomes less than the current holding i4) of the thyristor.

The recovery time of the paBHO-t 3r 3C juvenile one-shot one, (if the time is restored, the initial potential on capacitor 3 is restored to 0.95 Uo) The recovery time of the proposed one-shot is one sum of two times

where the charging time of the capacitor 3 along the circuit is a resistor 7, consisting of an open transistor 2, an open thyristor 1O with a constant g Cz (T) in the open state of the thyristor 10

(During this time, the voltage across the capacitor will increase by the value of ((); t 2 - the charge time of the capacitor across the circuit resistor 7, consisting of an open transistor 2, a resistor 6 with a constant time Cp (, K) when the thyristor is closed Yu (during this time the voltage across the capacitor will increase by the value of 0.95 Uo - 1) 2)

Since 1: / «-fe in view of the fact that 2 C and t 2. b in view of the fact that (0.95)" (0.95 Uo-U), To-fc + i -fc where UQ is the steady-state voltage on the capacitor 3;

the voltage on the capacitor 3 at the time of opening of the transistor 2; the voltage on the capacitor 3 at the time of closing the thyristor 10; . capacitor 3;

the transition resistance of the base emitter open transistor 2;

resistor 6; resistor 7;

open thyristor resistance 10,

Form ula invention

An emitter with one emitter and a jitching input and output transis-. Tori with a collector-base capacitive coupling, characterized in that, in order to reduce the recovery time, a thyristor, a diode and a differentiation node are inserted into Nezgo, during which the anode and the cathode of the thyristor are connected to the input transistor collector and the power bus, the diode is connected between the control electrode and the thyristor cathode in the opposite direction, and the anode and cathode of the diode are connected to the output terminals of the differentiation unit, one of the input terminals of which is connected to a power supply through a resistor and the other to lecturer output transistor Istochnshsh information received note in the examination

i ,. Itshok Ya. S. et al. Pulsed and digital devices. M., Sov. RadioH 1972, p. 305, fig. 20 (prototype).

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Claims (1)

Claim One-shot with emitter coupling, 20 containing input and output transistors, collector-base capacitive coupling, characterized in that, in order to reduce the recovery time, a thyristor, a diode ²⁵ and a differentiation unit are introduced into it, while the anode and cathode of the thyristor are connected respectively to the input collector the transistor and the power bus, the diode is connected between the control electrode and the cathode of the thyristor in the opposite direction, and the output terminals of the differentiation unit are connected to the anode and cathode of the diode, one of the input terminals of which is through a resistor oedinena with tire pit ³⁵ Niya, and the other - with the output transistor collector ..