SU377961A1 - POWER VOLTAGE GENERATOR - Google Patents

Description

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The present invention relates to the field of pulsed technology.

The known sawtooth generator, containing a charging transistor connected in series with a shaping capacitor, in parallel with which the discharge transistor, emitter follower and standby multivibrator, has a relatively large pedestal output voltage.

In order to reduce it in the proposed device, the base of the charging transistor is connected through a resistor to the collector of the additional transistor, the base of which is connected to the collector of one of the transistors of the waiting multi-driver.

The drawing shows a diagram of the proposed device.

The generator consists of a charging circuit on a charging transistor / with a controlled divider on an additional transistor 2; bit transistor 5; emitter follower transistors 4, 5, 6; waiting for the multi-transistor 7, 8.

At the moment of switching on the circuit, the transistor 7 of the waiting multivibrator is closed and the voltage on its collector is almost equal to the supply voltage U ,,

where f / cT is the voltage stabilized by the zener diode 9.

This voltage through the resistor 10 is fed to the base of the transistor: 2, opening it. The flow of current through the transistor 2, in turn, provides the necessary charge current through the transistor 1. As a result, the capacitor is charged //. Due to the use of a current stabilizing transistor 1 in the charging circuit, the capacitor 11 is charged with almost constant current.

The linearly-replaced voltage on the capacitor // through the emitter follower made by transistors 4, 5, 6, and the resistor 12 is fed to the base of the transistor 7 of the waiting recipient. As soon as it is

The pattern will exceed the voltage unlocked by the transistor 7, the multivibrator will be transferred to another stable state. At the same time, the voltage across the collector of the transistor 7 drops, and on the collector of the transistor 8 increases due to its closure. A decrease in the collector voltage UK at the transistor 7 will cause the transistor 2 to close. Its resistance will increase significantly, with the base current

transistor / sharply decreases and the charge current through it stops. At the same time, the voltage from the collector of the transistor 8 through the resistor 12 enters the base of the transistor 3 and opens it. Discharge occurs

the capacitor 11. Thus, at the moment

capacitor discharge // current through the charge of the transistor / does not leak.

The discharge time, i.e., the duration of the reversal of the niloil pattern, is determined by the constant time value of the multivibrator-state from the capacitor 13 and the resistor 14, as well as the resistance of the resistor 15. Then process, the process is repeated.

The use of such a control circuit for charging the capacitor 11 allows the pedestal of the output sawtooth to be reduced to zero.

The adjustment of the charging current, and, consequently, a smooth change in the frequency, is made by a variable resistor: 16. The use of a current-stabilizing charging circuit on the transistor in the circuit produces a nonlinearity coefficient of the sawtooth voltage of about 1%. The period of the generated voltage is 01-40 sec and is provided by the choice of capacitor 11 (0.05-100.0 microfarads).

The output sawtooth voltage of negative polarity is removed from the load of the emitter follower, series-connected resistors 17, 18.

Subject invention

A sawtooth voltage generator containing a charging transistor connected in series with a shaping capacitor, in parallel with which a discharge transistor, an emitter follower and a standby multivibrator, are different in that the output voltage of the charging transistor is connected through to the collector of the additional transistor, the base of which is connected to the collector of one of the transistors of the waiting multivibrator.