SU687568A1 - Symmeric multivibrator - Google Patents

Description

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The invention relates to a pulse circuit and can be used in pulse generators that synchronize the operation of various devices, for example, thyristor converters of direct current to non-temporal.

A symmetric multivibrator is known, containing two thyristors, the anodes of which are connected to each other via a switching capacitor, and through resistors to a power source, the cathodes are connected to the P1INOY power source and, via capacitors, to adjustable resistors 1. Such multivibrators are complex, have insufficient efficiency and dynamic range.

The purpose of the invention is to simplify the design, increase efficiency and scatter the dynamic frequency range of the multivibrator.

To do this, in a symmetric multivibrator containing two thyristors, the anodes of which are connected to each other through a switching capacitor, and through resistors to a power source, the cathodes are connected to a common power source, and through adjustable resistors. resistors are connected to the anodes and thyristor control electrodes.

The drawing shows a schematic diagram of the proposed multivibrator.

The multivibrator contains thyristors 1 and 2, resistors 3 and 4, which are the thyristor anode loads, switching capacitor 5, capacitors 6 and 7, resistors 8 and 9, 1 pins 10 and 11 of the power supply.

The device works as follows.

When power is applied, the capacitors 6 and 7 start charging through resistors 3 and 4 and adjustable resistors 8 and 9, respectively. Due to the inevitable variation in the parameters of thyristors 1 and 2, the control first opens one of the thyristors, for example, thyristor 1. In this case, capacitor 5 is charged through resistor 4 and open thyristor 1, capacitor 6 is discharged through adjustable resistor 8 and open thyristor 1, as well as the control electrode-cathode transition of the thyristor 1. At a later stage, the torpus 2 opens, and the voltage of the charged KOH.:ienc;i torus 5 is applied to the thyristor 1 in the opposite direction and closes it. The capacitor 7 is discharged through the resistor 9 and the open thyristor 2, as well as through the transition control electrode - the cathode of the thyristor 2. The capacitor 6 begins to charge through the resistor 3 and the adjustable resistor 8, and the capacitor 5 through the resistor 3 and the open thyristor 2. Further the cycle repeats.

To increase the output frequency of the multivibrator, the resistance of the adjustable resistors 8 and 9 is reduced. At high frequencies of operation of the multivibrator, the capacitors 6 and 7 do not have time to completely discharge when the corresponding opening is opened, their thyristors and charge faster before the voltage to be controlled by the thyristor electrode, at which the thyristors are turned on. This is equivalent to a decrease in the capacitance of the capacitors 6 and 7, as a result of which the frequency range of the multivibrator is expanded. In addition, the proposed multivibrator circuit increases its efficiency, since when a thyristor, for example, thyristor 1, is turned on, through adjustable

resistor 8 does not flow current under the influence of the power supply voltage. The offered multivibrator is simple in design and reliable in operation.

Claims (1)

1. Copyright certificate № 441644, cl. H 03 K 3/335, 12.28.72 (prototype).