SU440775A2 - Sawtooth generator - Google Patents

Description

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The invention relates to transistor blocking generator circuits widely used in automation, computing and electronics.

Known sawtooth generators made on the basis of block generators are characterized by a low thermal frequency stability.

The purpose of the invention is to increase the temperature stability of the frequency of the generated voltage.

This is achieved by introducing an additional feedback transistor, to the collector of which the base of the current-stabilizing two-pole transistor is connected, and a capacitor is connected between the base of the last transistor and the zero bus, the feedback winding is connected between the base and emitter of the feedback transistor and the midpoint of the resistive divider connected with the base winding disconnected from the base of the transistor current-stabilizing two-terminal.

The drawing shows a diagram of the device.

The generator contains a blocking generator on transistors 1 and 2, a current-stabilizing two-pole device on transistor 3, collector and emitter resistors 4 and 5 of feedback transistor 6, a capacitor 7 connected between the collectors of this transistor and

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a zero bus, a feedback winding 8 connected to the base and the emitter of the feedback transistor and the time specifying the capacitor 9.

The device works in the following way. When the power is turned on, the capacitor 7 is charged, as a result of which the potential of the base of the transistor 3 changes and, accordingly, the charging current is the time of the driving capacitor 9.

When the capacitor 9 charges d1ggs so much so that, on the emitter of transistor 1, it is compared with the voltage at the ball of transistor 1 and a blocking process occurs and the capacitor 9 is discharged. In the winding 8 an impulse occurs

opening for blocking time transistor 6. Through open transistor 6 and resistor 5, capacitor 7 is partially discharged, this changes the potential of the base, and hence the current of transistor 3. However, this change is insignificant due to the long time the capacitor discharges 7, NREVS, 1, for several orders of time, the period of generated pattern. Next, the capacitor 9 is charged and the whole process is repeated.

When the charging current of the capacitor 9 changes under the influence of any factors, i.e., when the period of the generated oscillator changes, the time of the discharge of the capacitor 7 changes accordingly, which will lead to a change in the base potential of the transistor 3 and

the charging current time of the drive capacitor 9 reaches the current value.

Subject invention

Generator sawtooth nair women auth. St. No. 287107, characterized in that, in order to increase the thermal stability of the frequency, an additional feedback transistor was inserted into the collector of which the base of the current-stabilizing two-pole transistor is connected, and a capacitor is connected between the base of the last transistor and the zero bus, and the feedback winding is connected between The base and emitter of the feedback transistor and the middle point of the resistive divider connected to the base winding are disconnected from the base of the current-stabilizing two-pole transistor.

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