RU1823135C - Saw-tooth voltage generator - Google Patents

Abstract

Usage: Sawtooth shaper can be used in oscillography. The inventive device comprises an input terminal 1, resistors 2, 8, transistors 3, 6. 7, an adjustable resistor 5, an output terminal 9. 2 il.

Description

The invention relates to pulsed radio measurement technology and can be used to generate sawtooth voltages in oscillography or other measuring equipment.

The purpose of the invention is to increase the linearity of the sawtooth voltage when obtaining amplitudes close in level to the voltage value of the power source.

In FIG. 1 is a schematic diagram of a driver; 2 is a timing chart.

The transistor sawtooth shaper (Fig. 1) contains an input terminal 1 connected through a resistor 2 to the base of the key transistor 3, the collector of which is connected to the collector of the transistor - an output signal amplifier 6 of the same conductivity type, output terminal 9, and the collector of an additional transistor 7 of the opposite type of conductivity and with the first lining of the charge capacitor 4, the emitter of the key transistor 3 is connected to an adjustable resistor 5, the second lining of the charge capacitor 4 and the base of the transistor is a force The signal el output Nala 6, the second end of the adjustable

the resistor 5 is connected to a common bus, the emitter of the transistor - the output signal amplifier b is connected to a common bus, the emitter of an additional transistor 7 is connected to a power source, and the base of the additional transistor through a resistor 8 is also connected to a common bus.

The transistor driver operates as follows.

When the power is turned on and there is no input signal at terminal 1, the transistor

3 is closed, and the additional transistor is the amplifier of the output signal 6, the transistor 7 is ajar by the base current, which is determined by the resistor 8, and further the additional transistor 7 acts as a current stabilizer. Charging capacitor

4 starts charging through transistor 7 and resistor 5. At the initial moment when the capacitor is just starting to charge, transistor b is open and the voltage at output terminal 9 will be minimal, i.e. about 0.2 V. As the capacitor 4 charges, transistor 6 starts to close and the voltage at output terminal 9 rises linearly. The linearity of the process is supported by the constant current of transistor 7. If not pre (L

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If the capacitor 4 is charging, the voltage at the output terminal 9 reaches almost the supply voltage. The value of resistor 5 can be changed. The charge rate of the capacitor 4 can be adjusted. I applied pulses to the transistor 3 to the input terminal 1, the capacitor 4 will quickly discharge through the open transistor 3. In addition, the opening pulse through the base-emitter junction of the key transistor 3 is supplied to the base of the transistor - the output signal amplifier b, creating an additional base current, which is added to the current flowing through the circuit through the additional transistor 7. As a result, the driver is reset to its initial state ry small period of time. This makes it possible to suppress very short surge pulses, leaving almost the entire period for the formation of a sawtooth voltage.

The parameters of the charging capacitor 4 of the adjustable resistor 5 are selected depending on the pulse repetition rate and the required amplitude of the sawtooth signals at the output. With appropriate selection of the resistance of the adjustable resistor 5, the amplitude of the sawtooth voltage at the output terminal 9 is adjusted over a wide range, up to the level of the supply voltage while maintaining the linear rise in voltage.

Compared with the known, the proposed technical solution has a number of advantages, namely:

-higher linearity;

-shorter recovery time;

- more complete use of the voltage value of the power source.

This shaper fully justifies itself in cases where it is required to de-energize the sawtooth waveform in high-voltage electronic equipment, for example up to several hundred volts, with high linearity requirements and short recovery time.

Claims (1)

SUMMARY OF THE INVENTION A sawtooth voltage generator comprising a first transistor, the base of which is connected to an input bus through a first resistor, a capacitor is connected to a first plate, a second plate is connected to an emitter of a first transistor and to a first terminal of a second resistor, a second transistor whose base is connected to the first output of the third resistor, the third transistor and the output bus, characterized in that, in order to increase the linearity of the sawtooth voltage when receiving amplitudes close in level the voltage of the power source, the second and third terminals of the second resistor are connected to a common bus, to the second terminal of the third resistor and to the emitter of the third transistor, the base of which is connected to the second capacitor plate, the first plate of which is connected to the collectors of the second and third transistors and to the output bus wherein the emitter of the second transistor is connected to a power line. + Ј, L 9 $ Dshod Figure 1