SU928630A1 - Comparator-one shot multivibrator - Google Patents

Description

(54) COMPARATOR-UNIFIER

The invention relates to a pulse technique and can be used in automation devices for determining the moment of equality of two signals AND the formation of a pulse of a given duration.

Known one-shot with a comparator on the input, containing the first operational amplifier, the non-inverting input of which is connected through the first resistor to the reference signal terminal, the inverting input connecting-. through the second resistor to the bus in the input signal, and the output through a series-connected capacitor and the third resistor is connected to the inverting input of the second op amp, the non-inverting input of which through the fourth resistor is connected to the bus of the first bias source and the output via the fifth resistor is connected to the inverting input the first operational amplifier; the inverting input of the second operational amplifier is connected via the sixth resistor to the bus of the second bias source Ij.

A known one-shot with a comparator at the input is triggered when the input, positive signal reaches the value of the positive reference voltage connected through a resistor to the non-inverting input of the first operational amplifier. The device can only compare unipolar, positive signals, which limits its functionality. In addition, it is quite difficult, since it contains two operational amplifiers, which in turn increases the power consumption of the device.

The closest in technical essence of the present invention

15 is a one-shot comparator containing an operational amplifier, the inverting input of which is connected via a resistor to the reference voltage bus, and the output to the zero-potential bus through a series-connected capacitor and a parallel-connected resistor and diode 2.

A disadvantage of such devices is low functionality.

The purpose of the invention is to expand the functionality.

To achieve the goal

Claims (2)

30, into the comparator-single-vibrator, containing an operational amplifier, the inverting input of which is connected via a resistor to the reference voltage bus, and the output to the potential-free bus through a series-connected capacitor and a parallel-connected resistor and diode, an additional diode connected between the capacitor's junction point and diode and an additional input of the operational amplifier, while the non-inverting and inverting inputs are connected through resistors and to the buses of the input signals. The drawing shows a functional diagram of the proposed comparator-one-shot. A one-shot comparator consists of an opera- tional amplifier 1, the resistors 2-4 are connected to the inputs, and the output of the operational amplifier 1 is connected through a series-connected capacitor 5 and a resistor b connected to the zero potential bus. Two diodes 7 and 8 are connected to the junction point of the capacitor and resistor. Diode 7 is connected by a cathode and parallel to resistor 6, an additional diode 8 is connected by an anode, and a cathode is connected to the input of the second amplification stage of operational amplifier 1, which is an additional input. Comparator one-shot works as follows. Bus 9, for example, is supplied with a positive positive voltage, which depresses opamp 1 in a negative mode. After a negative signal arrives, for example, bus 10 (or positive bus 11). The reference voltage exceeds the comparator-Novibrator tilts, the output of the positive rectangular signal, which charges the capacitor 5 through a resistor 6, At the time of the comparator overturns the one-shot at the junction point of the capacitor 5 and the resistor 6, the maximum positive potential is formed, which, according to the charge factor of the capacitor 5, decreases n and exponentially. This potential through the additional diode 8 goes to the input of the second. Cascade of the amplification of the operational amplifier 1, keeping it in the positive saturation mode and blocking the operation of the first amplification stage. As soon as the potential on the resistor 6 is reduced to the threshold value, the additional diode 8 is closed and the one-shot comparator returns to the initial state, and the capacitor 5 is reset by the diode 7. The one-shot comparator is ready for the next trigger signal. For normal operation of the device, the input voltage should be less than the reference voltage until the end of the formation of the output pulse duration. The proposed one-shot comparator has wide functional capabilities. It can compare both unipolar signals of any polarity, and opposite signals applied to the inverting and non-inverting inputs of the op amp, or it can work simply as a one-shot, triggered by a pulse of any polarity. Claims of a single-shot comparator containing an operational amplifier whose inverting input is connected via a resistor to a reference voltage bus and the output to a zero potential bus through a series-connected capacitor and parallel-connected resistor diode, in order to extend the functionality an additional diode is inserted in it, connected between the point of connection of the capacitor and the diode and the additional input of the operational amplifier, while non-inverting and inverting The connecting inputs are connected via resistors to the input signal buses. Sources of information taken into account in the examination 1. Rudkovsky J. Integral operational amplifiers. M., Mir, 1978, p. 261. 2. Gutnik.ov B.C. Integrated electronics in measuring devices. L., Energie, 04.22.80, p. 172 (prototype). tf0 - {1