SU1061257A1 - Device for amplifying pulse signals - Google Patents

Abstract

DEVICE FOR POWERFUL PULSE SIGNALS. containing an amplifier, between the input and output of which a capacitor is switched on, is necessary so that, in order to reduce the distortion of amplified impulses, between the output of the amplifier and its control input, a series differentiating circuit is connected, the first waiting multivibrator, And, the second standby multivibrator and integrator, the other input of which is connected to the output of the first multivibrating standby, and the second input of the element AND is connected to the output of the differentiating circuit. l am eating

Description

The invention relates to radio electronics and can be used in instruments and devices for measuring and recording electrical signals from sources with high internal resistance.

A device for amplifying pulse signals is known, which is an amplifier covered by one hundred percent negative feedback, in whose circuit the correction filter Ell is connected.

However, due to an insufficiently large input resistance, the known device can only be used in the current measurement mode, and the measurement of voltages in high-resistance circuits is impossible;

The closest to the proposed technical entity is a gain device for studying electrical signals of high-resistance sources, containing an amplifier, between the input and output of which a capacitor is connected and a manual adjustment element of the gain factor of the G2 amplifier.

A disadvantage of the known device is the inaccuracy of reproduction of amplified pulses from electrical and photoelectric signal sources, the internal resistance of which can vary over a wide range, such as photo-emf of semiconductors.

The purpose of the invention is to reduce the distortion of amplified pulses. The goal is achieved by the fact that a pulse amplifying device containing an amplifier, between the input and output of which is connected a capacitor, between the output of the amplifier and its control input, is connected in series with a differentiating circuit, the first waiting multivibrator, the And element, the second waiting multivibrator and the integrated reader, another the input of which is connected to the output of the first standby multivibrator, and the second input of the element I is connected to the output of the differentiating circuit.

FIG. 1 is a functional diagram of the proposed device for amplifying pulsed signals f in FIG. 2 is a time diagram of the operation of the device.

The pulse signal amplification device contains an amplifier 1, between the input and output of which capacitor 2 is connected, and between the output and control input - serially connected differentiating circuit 3 / first waiting multivibrator 4, element 5, second waiting multivibrator 6 and integrate reading 7, another input which is connected to the output of the first standby multivibrator 4, and the second input element And 5 is connected to the output of the differentiating circuit 3.

The device amplification of pulse signals works as follows

The input of amplifier 1 receives rectangular signals from a high-impedance source, signals appear at the output of this amplifier (Fig. 2a), the shape of which depends on the internal resistance of the source of signals, since the bandwidth of the device determines the constant time of the circuit. the bandwidth of the device in this case is achieved by compensating the input capacitance, i.e. the corresponding change (adjustment) of the gain of the amplifier 1, since the transition characteristic of such an amplifier has the form

one.

and

1 + poT-hp (r / 2)

Where

a

Rjj, U is the internal resistance and the voltage of the high-resistance source;

input capacitance and constant n-11 -f on / time amplifier 1; 2 is the capacitance of capacitor 2. When the internal resistance R of the source changes, the gain K of amplifier 1 is required to ensure its transient response close to aperiodic with the shortest front. The output signal of amplifier 1 (Fig. 2a) is applied to the differentiating circuit 3, and the output voltage of the differentiating circuit 3 (Fig. 26) with its positive pulses triggers the first wait multivibrator 4, the pulse width of the first wait multivibrator 4 (Fig. 2c) 10- 20% less than the duration of the recorded pulses. Its pulses go to one input of integrator 7, the output voltage of which (Fig. 2e) goes to the control input of amplifier 1 and changes its gain, thereby changing the equivalent capacitance of the device. In the case of a slight overcompensation of the input capacitance of the device, the signal at the output of the differentiating circuit 3 (Fig. 26) has a negative overshoot, in this case the element And 5 is triggered and the second waiting multivibrator b is triggered, the output signal of which is

about 10% less than the signal of the first standby multivibrator 4. and has the opposite polarity. This signal (Fig. 2d) is fed to the second input of the integrator 7 and changes its output voltage in the opposite direction, which leads to a change in the opposite direction of the gain of amplifier 1 (the dashes in Fig. 2e show the voltage and Signals from multivibrator 4 and 6 separately). This results in a transient response of the amplifier. 1 with the shortest duration of the output voltage front.

Thus, the introduction into the device with a compensated input capacitance of the differentiator, two waiting multivibrators, the logic element AND and the integrator leads to a decrease in the amplitudes of the amplitudes of the pulses, thus providing an increase in the accuracy of reproduction of the pulsed signals compared to the prototype.

Claims (1)

A PULSE SIGNAL AMPLIFICATION DEVICE, comprising an amplifier, a capacitor between the input and output of which is switched on, which is necessary because, in order to reduce distortion of amplified pulses, a series differentiating circuit is connected between the amplifier output and its control input, . The first standby multivibrator, AND element, the second standby multivibrator and integrator, another input of which is connected to the output of the first waiting multivibrator, the second input of the element And is connected to the output of the differentiating circuit. sho m>