SU790106A1 - Filter for pulse signals - Google Patents

Description

(54) FILTER FOR PULSE SIGNALS

I

The invention relates to electronics and pulsed technology.

A device for filtering low frequency pulse pulses is known, comprising a series-connected power source, a charging resistor and a chain consisting of a dynistor, a load resistor and a thyristor, in parallel with which a storage capacitor 1 is connected.

A disadvantage of the known device is that even if there are pulses at the input, which follow at a frequency higher than the cutoff frequency, there will still be pulses at the output that follow at the device’s own oscillation frequency, i.e., the known device is a filter for pulses of low frequency.

The purpose of the invention is to extend the functionality.

To achieve this goal, a filter for pulse signals containing a series-connected power source, a charging resistor and a chain consisting of a dynistor, a load resistor and a thyristor, in parallel with which a storage capacitor is connected, are connected in parallel with a storage capacitor in series by an additional load resistor and a resistor, as well as a threshold switch, the signal input and output of which are connected to the control electrodes, respectively - the thyristor and additional thyristor.

The drawing shows a basic electrical filter circuit for pulse signals.

The filter for pulse signals contains a series-connected power supply 10 of charge 1, a charging resistor 2 and a chain consisting of a dynistor 3, a load resistor 4, a thyristor 5, in parallel with which a storage capacitor 6 is connected, and of the series-connected additional load resistor 7 and additional thyristor 8. Parallel to the capacitor 6, a threshold switch 9 is also connected, the signal input and output of which are connected respectively the gate electrodes of thyristor 5 and the auxiliary thyristor 8.

The device works as follows.

While the follow-on pulse time period t is longer than the one-vibrator tp own relaxation period, they pass to the output, because during the time between two pulses, the capacitor 6 has time to be charged before the voltage of the transistor 3 UUP and at the moment the pulse arrives at the thyristor control electrode 5, the capacitor 6 is quickly discharged through the dynistor 3, the resistor 4 and the thyristor 5, forming a pulse on the resistor 4. The key 9 does not transmit the triggering pulse to the thyristor 8, since with the control input voltage (removed from the capacitor 6), more An equal voltage breakdown dynistor 3 Unp, it is locked. If the period of the incoming pulses T is less than the proper relaxation period of the one-shot fp, then they do not pass to the output, because during the time between two pulses the capacitor 6 does not have time to charge before the voltage of the unidistor 3 Unp and therefore the dynistor 3 at the moment of arrival the trigger pulse to the thyristor 5 does not break through. The key 9, with a control voltage (removed from capacitor 6) lower than Unp, is open and transmits the same pulse to thyristor 8, as a result of which the latter opens and quickly charges through itself (and resistor 7) capacitor 6, etc. Thus, the cut-off frequency of the filter is determined by the natural relaxation period of the one-shot, which depends on the values of the charging resistor 2 and the storage capacitor 6. By changing them, you can change the cut-off frequency.

If you remove the output pulses from the resistor 7 (out 2), then this circuit works as a filter for high frequency pulse pulses. However, the amplitude of the output pulse decreases with an increase in the follow frequency (since the time for charging the capacitor 6 remains less and less).

At some high frequency, the voltage on the capacitor 6 becomes insufficient to unlock the thyristor 8. But in modern thyristors, the ratio of the maximum anodic voltage to the minimum is, for example, 10. This means that if, for example, you set the cut-off frequency to 20 Hz. then up to a frequency of 20 kHz, the high-frequency pulse-pulse filter is operational. In most cases, such a frequency difference satisfies the necessary technical conditions.

Claims (1)

Invention Formula A filter for pulse signals containing a series-connected power source, a charging resistor and a chain consisting of a dynistor, a load resistor and a thyristor, in parallel with which a storage capacitor is connected, characterized in that, in order to enhance the functionality, the capacitor are connected in series with an additional load resistor and thyristor, as well as a threshold switch, the signal input and output of which are connected to the control electrodes respectively and the thyristor auxiliary thyristor. Sources of information taken into account during the examination 1. R. Bilik and others. Pulse circuits J on dynistor and thyristor. M., “Science, 1966, p. 142