SU1474829A1 - Single-shot multivibrator - Google Patents

Abstract

The invention relates to a pulse technique and can be used in the construction of time interval formers that can be used in radio installations, electronic ignition devices. The purpose of the invention, the expansion of the field of application of the one-shot, is achieved by the possibility of promptly changing the duration of the output pulse. For this purpose, a voltage limiter, a second comparator, a resistor, and a current source are added to the one-shot. In addition, the one-shot contains trigger 1, input bus 2, time interval to voltage converter 3, current source 5, resistor 6, first 7 and second comparators 8, voltage limiter 9, reference voltage source 10. In this case, the converter 3 is made on an operational amplifier 11, a resistor 12, a diode 12 and a capacitor 14. A control voltage is supplied to the second input 15 of the operational amplifier. The output of comparator 7 is the output of the device. 2 Il.

Description

and the output of the first comparator 7 is the output of the one-shot.

“A single vibrator works as follows.

In the absence of input pulses, the output voltage from the output of the trigger 1 is zero, the voltage at the output of the converter 3 of the time interval to the voltage value is equal to the time moment and 3

40

t3 (Fig. 2), the voltage from the output of the converter 3 will voltage across the inverting input of the comparator 8 and a voltage will form at its output, from which trigger 1 returns to its original position and the output of amplifier 11 will become negative and through low resistance open diode

a voltage level determined by a level of 45 C, the capacitor 14 will quickly discharge

It limits the limiter 9. The voltage of the source 10 of the reference voltage UT, which sets the delay time of the pulse being formed, is greater in magnitude than the voltage from the output of converter 50 and it is fed to the inverse of the first comparator 7, the output of which is equal to zero . From the current source 5, the current flowing through the resistor 6 creates 55 nekot on it a voltage Uff, which is added to the voltage UT, and therefore on the inverse of the comparator

(to increase the discharge current, when this is necessary, the capacitor 14, instead of a diode transition, includes a junction of the transistor, a resistor, included in the current amplification circuits).

After the voltage level reaches the voltage limit of the voltage suppressor 9, the further discharge of the capacitor stops. The limiter passes the current from the output of the converter or the additional connection (not yet), abruptly decreases or stops

time point and 3

t3 (Fig. 2), the voltage from the output of the converter 3 will exceed the voltage. At the inverting input of the comparator 8 and at its output a voltage is generated, from which the trigger 1 returns to its original position and at the output of the amplifier 11 the voltage will become negative and through a small open diode resistance

h will quickly discharge capacitor 14

(to increase the discharge current, when necessary, the capacitor 14, instead of a diode transition, includes a junction of a transistor, included in the current amplifier circuit).

After the voltage level reaches the voltage limit of the voltage limiter 9, the further discharge of the capacitor is stopped. The limiter passes the current from the converter output either through an additional connection (not shown), abruptly reduces or terminates

capacitor discharge current level 14. In the future, all processes occur similarly.

Changing the current from the output of current source 5, and consequently, the voltage UQ and the time between the moments of excess voltage from the output of converter 3 over voltage UT, change the duration of an advantageous pulse at a constant delay time of the leading edge of the output pulse from the moment the input pulse on the input bus 2.

Changing the voltage Ur, changes the delay time of the leading edge of the output pulse at a constant output pulse duration.

By changing the UQT of the limiter 9, the time from time t4 to time T5 i.e. range of time delay.

Using the value of the current source 5 current, the duration of the output pulse can be set both very small (in the limit to the speed of the comparator 7) and very long (in the limit from time t to time t) for he | x

ten

15

five

0

variable time constant converter 3.

Claims (1)

Invention Formula A single-vibration device containing an input bus connected to the first trigger input, the output of which is connected via a time converter to a voltage value to the first input of the comparator, the second input of which is connected to the source of the reference signal, and the output to the output bus, characterized in that In order to expand the scope of application due to the possibility of promptly changing the duration of the output pulse, a second comparator, a resistor and a current source are introduced into it, and the output of the time interval converter in The voltage is connected to the first input of the second comparator, the second input of the first comparator is connected to the second input of the second comparator and the current source output through a resistor, and the output of the second comparator is connected to the second trigger input.