SU369684A1 - GENERATOR OF MULTIPOLAR PULSES - Google Patents

Description

one

The invention relates to a pulse technique and can be used in automation, telemechanics and computer technology.

Generators of different-polarity pulses are known that contain an unstabilized power source, a stable frequency pulse generator, to the output of which a matching transformer is connected, a multivibrator with two transistors, the collectors of which are connected to opposite terminals of the output transformer winding, and the bases to the feedback windings of this transformer.

However, the known generators have a low efficiency and low steepness of the fronts of the generated pulses.

In order to increase the efficiency and increase the steepness of the fronts of the generated pulses in the proposed generator, the secondary winding of the matching transformer is connected directly to the bases of the transistors of the multivibrator and simultaneously through the diodes to the emitters of the same transistors, connection of the output transformer, the middle terminal of which is connected to the positive pole of the power source.

FIG. 1 shows the principal electrical circuit of the proposed generator; in fig. 2 is a diagram of voltages at various points of the circuit.

The generator contains a multivibrator including a transformer / on a core of a material with a rectangular hysteresis loop and transistors 2 and 3. A generator of 4 stable frequency square impulses made according to any scheme is connected by means of a matching transformer 5 to a multivibrator operating in synchronization mode . The collectors of transistors 2 and 3 are connected to opposite ends

transformer primary winding 6. The bases of the transistors 2 and 3 are connected to the windings 7 and 5 of the transformer /, which are the feedback windings. The secondary winding 9 of the matching transformer 5 is connected to the bases of transistors 2 and 3, and through diodes 10 and 11 to their emitters. The additional secondary winding 12 of the transformer 5 is connected via diodes 13 and 14 to the connection point of the windings 7 and 5.

transformer 1. The middle terminal of the winding 12 of the transformer 5 is connected to the positive pole of the power source connected to terminals 15 and 16. The winding 17 of the transformer 1 is the output winding loaded onto the load 18.

The scheme works as follows.

When remaking the core of the transformer 1 under the action of a voltage applied to one of the halves of the nervous winding 6, one traisistor (for example, transistor 2) is open by the positive feedback from the base winding 7, the transistor 3 is closed, while the positive feedback is The voltage must be greater than the positive bias voltage by an amount sufficient to maintain the open transistor 2 in a saturated state. The transistor 3 is kept in a locked state by a sum of positive feedback voltages and bias. When a transformer / saturation induction is reached in the core, the collector current of transistor 2 increases due to an increase in the magnetizing current of the transformer, transistor 2 goes out of saturation, the voltage on its collector winding and base winding 7 of the feedback drops, and transistor 2 closes.

Since the transistor 3 also remains in the closed state due to the bias voltage, the voltages on all the windings, including the output winding 17, are equal to the bullet. The circuit is in this state until the arrival of the t / c switching pulse (Fig. 2) of synchronization. The plus of the trigger pulse t / u through the diode 10 is fed to the emitter of the transistor 3, and the minus directly to the base of the transistor 5 and opens it. A supply voltage is applied to the collector winding, and in the base winding 8 a voltage iolol occurs: positive feedback, a greater bias voltage. The transistor 3 is kept open by positive feedback. When achieved by induction in the core

a transformer I of a certain size, the process of locking the transistor 3 takes place, while prior to the arrival at the base of the transistor 2 a triggering pulse t / c. Since the triggering / 7z arrives at the bases of transistors 2 and 3 alternately through a half-period G / 2 synchronization voltage f / c, then at the generator output different polarity pulses f / n are obtained, the period T of which

coincides with the period of operation of the generator 4 stable frequency. The amplitude of these pulses is proportional to the supply voltage, the duration of these pulses is determined by the time of complete magnetization of the transformer core /.

Subject invention

A generator of bipolar pulses, containing a non-stabilized pitapi source, a stable frequency generator, to the output of which a matching transformer is connected, a multivibrator on two transistors, the collectors of which are connected to the opposite terminals of the winding of the output transformer, and the bases to the feedback windings This transformer, characterized in that, in order to increase the efficiency of the generator and

increasing the steepness of the fronts of the generated pulses, the secondary winding of the matching transformer is connected directly to the bases of the transistors of the multivibrator and at the same time through the diodes to the emitters of the same

transistors, and an additional secondary winding of the matching transformer is connected via diodes to the connection point of the feedback windings of the output transformer, the middle terminal of which is connected to the positive pole of the power supply.

T / 2

yj

i

FIG. 2