SU1228220A1 - Pulser - Google Patents

Abstract

The invention can be used to build pulsed generators with a sufficiently high frequency stability of the generated pulses. The generator contains element 1 NOT, resistors 2, 4 and 6 element 3 AND-NOT and capacitor 5. Introduction to the device element IS-NOT, resistor 6 and the formation of new connections between the element. By means of the device, it is possible to more clearly link the magnitude of the voltage jumps on the left capacitor plate to the threshold voltage. 3 il. SL FIG.

Description

I,

The invention relates to a pulse technique and can be used to build pulse generators with a sufficiently high frequency stability of the generated pulses.

The purpose of the invention is to increase the frequency stability of the generated pulses due to a more explicit linking of the magnitude of the voltage spikes on the left capacitor plate to the threshold voltage.

FIG. 1 is a schematic diagram of the generator; in fig. 2 and 3 - timing diagram of the generator.

The pulse generator contains a logical element NOT 1, the output of which is connected to its input through the first resistor 2 and to the first input of the second logical element AND-NE 3, the output of which is connected to its second input through the second resistor 4 and the inputs of element 1 through a capacitor 5 the third resistor 6, which connects the input of the element 1 with a common bus.

The pulse generator works as follows.

Consider the operation of the generator from the moment when the left capacitor plate (point a, fig 1) is charged to its maximum value. At element 1 and at the first input of element 3 (point 5) there is a low level, therefore, at the output of element 3 (point g) it is level 1. However, it is slightly below the static level due to the limited output current of the logic element and gradually approaches it as PodAhardda im right capacitor plates 5,

The left capacitor plate is 5 times pressed through resistors 6 and 2. When the threshold level is reached, the transition of element 1 to state 1 begins, but as a result of negative feedback, it is delayed, as indicated by the initial step at the output of element 1 (Fig. 3a ). When the voltage at the point a (Fig. 1) reaches the threshold value, the element 1 switches to the upper state. Element 3 switches to the lower state, and the transition of its output voltage to O is transmitted to the left side of capacitor 5. Lastly, the current 1 of element 1 starts to be charged through resistor 2 and current through resistor b, because

28220

the initial voltage at point a is below zero. When the level of this level is transferred to the positive part, the resistor 6 starts to be shunted by the solid circuit, but this phenomenon is eliminated; negative feedback. Element 1 begins to produce a current that exceeds the nominal, and the output voltage decreases (Fig. 3a). The current element 1 is switched to the lower state, the element 3 to the upper one, the voltage drop is transmitted to the left capacitor plate 5 and the process is repeated,

J, Since an increase in the voltage between the voltage and temperature and an increase in the difference between the voltage t and the threshold voltage is observed, in both cases there is a similar change in the processes of

five

WITH

3

rezer yes condenser at a

(FIG. 2a). Due to the fact that when the shed is located, the element 3 in the lower state, one of its inputs, is connected to the output through a resistor 4, at the & a threshold voltage is established (fig ,, zg), and at the point - r. - some residual, not dependent

only from resistor 4, but also from voltage to voltage.

Oscillation frequency stabilization

C) of the generator is carried out due to a more explicit binding of the magnitude of the voltage jumps at the output of the element 3 and, accordingly, on the left capacitor plate to the threshold.

Since the discharge of the capacitor actually goes through a parallel circuit of resistors 2 and 6, the resistances of the resistors significantly exceed the resistance; neither the prototype resistors and the left side charge approaches the charge from the current source, and the accelerating action is controlled by the value of the resistor 6, Therefore, with an increase in supply voltage or temperature, the charge goes not parallel to the initial one (Fig. 2a and B, dashed line), but with compensation for an increase in the discharge time. Moreover, the more accurate the compensation is, the more it corresponds to: the change in the discharge time and the change in the output jump

 the voltage of element 3. For this, it is necessary that the residual voltage changes according to the same law. Since the magnitude of the latter is set by a threshold voltage and a resistor 4, the coS resistance of this resistor must be equal to the resistance of the discharge circuit of the left capacitor plate, or parallel-connected resistors 6 and 2.

Claims (1)

Claims An impulse generator containing a logical element NOT, whose input through the first resistor is connected to its output and through a capacitor to one of the terminals of the second resistor, characterized in that, in order to increase the frequency stability of the generated pulses, element and NOT and third 228220 a resistor, one output of which is connected to the input of the logical element NOT, and the other with a common bus, the output of the logical element AND-NOT is connected to the connection point of the capacitor and the second resistor, the other output of which is connected to one of the inputs of the logical element AND-NOT, another input which is connected to the output of the logical element NOT. St i / 8 t / 5 Un fib.Z Compiled by N.Feropontov Editor I.Rybchenko Tehred N.Bonkalo Corrector V.Sinitska  -.-.-- .. j. . ", E, i ™. ™ --- - - - - - --- - - - - Order 2294/55 Circulation 816 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4