SU382226A1 - FANTASTRONOUS AUTOGENERATOR - Google Patents

Description

one

The device relates to a pulse technique, in particular, to saw-tooth voltage generators operating in self-oscillation mode, and can be used in the design of small-sized equipment operating in harsh mechanical and climatic conditions.

Known are fantastic oscillators, formed on three diodes of the same conductivity type.

However, these oscillators in unstable climatic conditions are unstable: when testing generators, their oscillations fail even with slight changes in temperature and supply voltages; the change of transistors and other elements of the generator also causes the disruption of the self-oscillating mode.

In order to increase the stability of the self-oscillating mode of operation in the proposed autogenerator, a transistor of the opposite type of conductivity is connected to the base divider of one of the transistors (the first), the base of which is connected to the collector of the first transistor through the capacitor to the second and the third emitter, respectively, through a diode and resistor.

FIG. 1 is a schematic diagram of the proposed auto generator; in fig. 2 - time 9

Variable diagrams but noting the operation of the oscillator.

The proposed oscillator contains transistors 1, 2, p 3 of the type pnp. The base divider (resistors 4 and 5) of the transistor / includes a pnp transistor 6, the base of which is connected through a capacitor 7 to the collector of the transistor /, through a diode 6 to the collector of transistor 2, and through a resistor 9 to the emitter of transistor 3. The resistors W and // are included in the collector resistances of the transistors / and 2, respectively, and the elements 12-16 serve for a thermal stabilizer w. The capacitor U7 and the resistor 18 form a time master circuit.

The operation of the nilo-shaped generator of the fantastic type in the self-oscillatory mode is characterized by the following cycles (see Fig. 2):

/ o- / 1 - the direct course of the nila;

ii- / 2 - reverse saw; L / 1 - the process of overturning the circuit after the forward course of the nila; - the process of overturning the circuit during the return stroke of the saw (for 1 time interval L / | n A / a is conditionally selected).

With the help of transistor 6, kapdensator 7, diode 6 and resistor .9 in the generator eliminated breakdowns of the cycle L / 2, which provides a stable

the self-oscillation mode, even if the gain of the transistor is changed several times, and the voltages of the sources EI and EZ change within 30%.

In the autogenerator, for the duration of the time, the following physical processes take place.

Until moment / 2, transistor 2 is closed, and transistor 1 is open. The voltage UK., On the capacitor 17 is increasing. The transistor 6, through which the bias is applied to the base of the transistor /, is open (this is achieved by selecting the appropriate value of the resistor 9), while the diode 8 is closed. As soon as the voltage across the collector of transistor 2 becomes higher than the source voltage E2 (E2 is chosen to be lower EI) by the value of / 8 (t / 8 is the voltage drop across the diode 8 in the open state), the transistor 6 starts to close, and the voltage (/ 6i) on the base of the transistor / nadal, and the voltage (f / Ki) on the collector of transistor 1 increases.

The voltage change U through the capacitor 7 is transmitted back to the base of transistor 6, causing it to be further locked. The evolving avalanche-like nroness of locking transistor 6 causes it to be reliable.

The voltage U & abruptly drops, as a result, the transistor closes / and transistor 2 opens. After the avalanche-like process is completed, the voltage (b) increases, but the transistor / remains closed because the transistor 3 is opened by the collector voltage of transistor 3 after the transistor 2 is unlocked .After opening the transistor 2, the saw starts to move.

Subject invention

A fantastic oscillator containing a transistor whose emitter is connected to the second emitter and the third collector

transistors, a compensating diode connected between the base and the emitter of the third transistor and a capacitor connected between the third base and the collector of the second transistor, characterized in that, in order to increase the stability of the self-oscillating mode of operation, the base of the first transistor opposite the first transistor conductivity type, at

This base additional transistor connected through a capacitor to the collector of the first, through a diode to the collector of the second and through a resistor to the emitter of the third transistor.