SU884086A1 - Multivibrator - Google Patents

Description

(54) MULTI-VIBRATOR

one

The invention relates to the field of pulsed technology and can be used in the instrument-making and radio engineering industry.

The multivibrator is known using an additional power source in the base bias circuit C J The disadvantage of this modification is the use of two power sources and the dependence of the pause (duty cycle) duration on the source voltage in the emitter circuit of the first transistor.

A known emitter-time multivibrator with a master circuit contains two i $ transistors and requires two power sources 2.

The disadvantage of this device is the presence of two power sources and the dependence of the moment of opening the first transistor on the magnitude of the voltage of the first power source.

The purpose of the invention is to simplify the device and increase the temperature stability of the frequency.

The goal is achieved by the fact that the multivibrator containing the first and second transistors, the emitters of which are interconnected, connect the base of the first transistor to the oyc bus and the collector of the first transistor and through a resistor with a power supply bus, a semiconductor element with a 5-shaped characteristic is introduced connecting the collector and the emitter of the first transistor, and a dynistr is used as such an element.

The drawing shows the prialp electric circuit of the multivibrator.

Claims (2)

The multivibrator contains the first I, the second 2 transistors of the p - p - p type, the charging resistor 3, the capacitor 4, the lecture resistor 5, the discharge resistor b, direction 7. The bass of the transistor 1 is connected to the common power supply line and the emitter - through a resistor 3, parallel to which is connected a chain of series-connected capacitor 4 and resistor 6, the common point of which is connected to the emitter of transistor 2. The collector of transistor 2 is directly connected to the power supply bus and the base to the collector of the inhibitor 1 directly via a resistor 6 with a power supply bus, the emitter-collector junction of the transistor t is connected parallel to the ano-cathoc junction 7. The multivibrator works as follows. In the initial state, transistor 1 is closed due to the voltage drop across resistor 3, and transistor 3. is open. The capacitor 4 charges from the power source along the circuit: common power supply bus, resistor 6, emitter-collector junction of transistor 2, power supply bus. When the voltage OQ on the capacitor 4 reaches the value of the switching voltage of the dynistor 7 (the voltage (jf-, is applied to the dynistor in the forward direction through the emitter-base of the open transistor 2), it goes to the open state. -mitter of transistor 2 applies a positive potential, pasw the voltage difference across capacitor 4 and direct voltage drop across dynistor 7, transistor 2 closes, which leads to opening of transistor 1. When opening transistor 1, the anode-cathode of distor 7 opens bypassing the emitter-collector of the open transistor I and the wild torus 7 close. A capacitor 4 is quickly discharged through a resistor 6 and an open transistor 1, the transistor 1 closes and the transistor 2 opens, the generation process is repeated. 6 with a common base simplifies the multivibrator circuit (there is no voltage divider or a second power source), it increases the stability of operation, since the moment of operation depends only on the value of the operating voltage Ani dynistor connected in series with a transition base - emitter voltage of the second transistor multivibrator open and is defined by the difference voltage (J direct incorporation dynistor and voltage A and willow emitter-base junction of transistor open Is Ip - uU y {I). When the thermal regime of the circuit changes, for example, as the temperature rises, U v U Ug decreases. Therefore, the drives Uj-,, defined by relation (1) does not change. Claim 1. Multivibrator containing the first and second transistors, the emitters of which are interconnected through time defining a capacitor and through resistors - with a common power supply bus, the base of the first transistor is connected to a common bus, and the second transistor and through a resistor with a power supply busbar, different t & l, that, in order to simplify the device and increase the temperature frequency stability, a semiconductor element with an S-characteristic connecting the collector and emitter of the transistor. 2. The multivibrator according to claim 1, which is based on the fact that a dynistr is used as an element with a 9-characteristic. Sources of information taken into account in the examination I Doronkin EF Transistor impulse generators, Connection, 1968, p. 83 2. Handbook of pulse technology. Ed. Yakovlev, Technique, 1972, p. 231, fig. 6-1