SU1190474A1 - One-shot multivibrator - Google Patents

Abstract

SINGLE VIBRATOR containing two transistors with resistive circuits of the base bias and resistors of the collector and emitter loads, the first time specifying a capacitor connected between the collector of the first and the base of the second transistor, and the input capacitor. / 3 is connected between the startup bus and the base of the first transistor, characterized in that, in order to expand the functionality of the device, a second time setting capacitor connected between the emitters of the first and second transistors, the third transistor, blocking capacitor, control voltage source is introduced into it and the integrating RC circuit is connected to the base circuit of the third transistor, the resistor of the integrating RC circuit is connected to the control voltage source bus, the emitter of the third transistor is connected to the emitter m of the first transistor, a collector connected through a blocking capacitor to the emitter of the second transistor through a resistor, and - with its emitter. 17 18 Ui / np.

Description

The invention relates to a pulse technique and can be used to normalize the amplitude of the incoming electrical signals.

The purpose of the invention is to expand the functionality of the device by providing work with pulses of any shape while maintaining noise immunity to white noise and high resolution with short trigger pulses.

FIG. 1 shows a circuit diagram of a single vibrator; in fig. 2 - time diagrams; a typical sequence of triggering pulses (a), in this case, the control voltage form (b) is necessary, the time dependence of the response threshold (c), the sequence of single-pulse output pulses caused by the triggering pulses shown in diagram I (d) and the dependence of the output one-shot pulse from the time interval after the time tj (e) explaining the work of the proposed one-shot.

The single-oscillator contains the first 1 and second 2 transistors with resistive circuits of the base bias, formed by resistors 3-6 with resistors 7, 8 and 9, respectively, collector and emitter, respectively. loads, the time specifies the capacitor 11 connected between the collector of the first 1 and the base of the second 2 transistors, the input capacitor 12 connected between the start bus 13 and the base of the transistor 1, the second time specifies the capacitor 14 connected between the emitters of transistors 1 and 2, the third transistor 15, the base circuit of which includes an integrating RC circuit containing a capacitor 1b and a resistor 17 connected to the bus of the source 18 of the control voltage, the emitter of the transistor 15 is connected to the emitter of the transistor 1, the collector through the blocking capacitor 19 is connected to the emitter of the transistor 2 and through a resistor 20 to the emitter of the transistor 15.

The single vibrator works as follows.

In the initial state, the first stage (transistor 1 and resistors 7 and 9) is in the amplifying mode, due to the choice of the values of the resistors 3 and 4 of the base bias circuit. The second stage (transistor 2 and resistors 8 and 10) at the same time is in a state of light saturation due to the choice of the values of resistors 5 and 6 of the base bias circuit and a large resistor 9 of the collector load. With a zero control voltage (diagrams a and a segment up to point t of diagram b, fig. 2), the transistor 15 is closed and the emitters of transistors 1 and 2 are connected only after a second time specifying a capacitor 14. Upon the arrival of a positive impulse: a starting pulse (Fig 2a) a pulse I generates a short positive pulse at the output, determined by the value of the capacitor 14, (Fig. 2a, the pulse I. Diagrams d) In this case, the triggering pulse is amplified by the first cascade and the second cascade is avalanched until the end of the recharge cycle of the capacitor 4, which causes an avalanche end of the output pulse. At the same time, the first time 5 of the driving capacitor 11 does not have time to significantly affect the processes occurring in the circuit due to the small duration of the output pulse.

The trigger threshold, despite the amplifying effect of the first stage, is quite high. In this case, the thresholds for short and long trigger pulses are close in magnitude. At time t (Fig. 26), when a low flat (long) start pulse is expected to arrive (pulse, Fig. 2a), a positive control voltage is applied (Fig. 26). After some time, due to the charge of the capacitor 16, the transistor 15 opens to saturation, while the capacitor 16 prevents the one-shot from tripping on the leading edge (Fig. 26). The capacitor 19 blocks the second time the driving capacitor 14. At the same time, the first time the driving capacitor 11 takes effect, determines the output pulse for the J1 (pulse IV, (Fig. 2d). Resistor 20 provides the discharge of the capacitor 19 after the end of the operating cycle.

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Claims (1)

A SINGLE-VIBRATOR containing two transistors with resistive circuits of basic bias and resistors of collector and emitter loads, a first time-setting capacitor connected between the collector of the first and the base of the second transistor, and an input capacitor connected between the start bus and the base of the first transistor, characterized in that, for the purpose of expanding the functionality of the device, it introduced a second timing capacitor included between the emitters of the first and second transistors, the third transistor, blocking the first capacitor, the control voltage source and the integrating RC circuit included in the base circuit of the third transistor, the integrating RC resistor is connected to the control voltage source bus, the emitter of the third transistor is connected to the emitter of the first transistor, the collector is connected through the blocking capacitor to the emitter of the second transistor and through the resistor - with its own · emitter. ®