SU1431052A1 - Pulse expaneder - Google Patents

Abstract

The invention relates to a pulse technique and can be used in devices for processing and generating pulse signals. The purpose of the invention is to increase the pulse expansion accuracy by introducing a limiter 10, an operational amplifier 3 and a third diode 7 into the bus device 1I. In addition, the device contains an input bus 1, a comparator 2, a capacitor 4, diodes 5 and 6, resistors B and 9, the output bus 12. Resistors 8.9 and diodes 6 and 7 constitute element 13 of the recharge. Limiter 10 provides control of the pulse expansion ratio. In this case, different elements will be applied to the diode of the recharge element 13, with different fields, voltages, as a result of which the recharging rates of the capacitor 4 will be different. 2 or. “S

Description

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The invention relates to a pulse technique and can be used in devices for processing and generating pulse signals.

The purpose of the invention is to improve the accuracy of the expansion pulses.

Figure 1 shows an electrical functional diagram of the device; 2 shows timing diagrams for his work. The pulse expander contains input bus I, comparator 2, operational amplifier 3, capacitor 4, three diodes 5-7, first 8 and second 9; resistors, limiter 10, control bus 11, output bus 12. At this, the input bus is connected to the right : the input of the operational amplifier 3 and the inverse input of the comparator 2, pr - the 1st input of which is connected to the common bus, and the output - to the output of the limiter: bodies and the first terminals of the resistors 8 1 and 9, the second terminals of which are through diodes 7 and 6, respectively connected to the | junction point of capacitor 4 and | diode 5, as well as to the inverse th input | operational amplifier 3, the output Ko JTOporo coupled to output bus 12, control bus 11 is connected to the input of the limiter. Resistors 8 and 9 and diodes 6 and 7 make up element 13 overcharge.

: The device works as follows.

I In the absence of input pulses | on bus 1 (Fig. 2a) from the Ufix source, Comparator 2 is set to a state at which the output of its: positive voltage is set. A positive-polarity current flows through the over-charge element 13, in conjunction with the rms on the code of the operational amplifier 3, the voltage of the negative polarity is established (Fig. 2b) with an amplitude equal to the voltage drop across the open diode 5.

The voltage on the bottom plate of the capacitor is close to zero. The voltage on the top plate of the capacitor is also zero. Thus, a forced zeroing of the capacitor in standby mode is achieved.

During the formation of a pulse on the bus 1 of positive polarity from the output of the comparator 2, a negative polarity voltage is formed (Fig. 26),

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at the output of the operational amplifier 1, the voltage of the positive polarity from which the diode 5 is shifted in the opposite direction.

During the duration of the input pulse, the capacitor 4 is charged by a negative voltage across the circuit: the output of comparator 2 - resistor 8 - diode 7. After the formation of the input pulse completes, the voltage at the inverting input of comparator 7 becomes zero and a positive potential is formed at its output , and at the output of the operational amplifier 3, the voltage of its sign does not change, because the voltage of negative polarity on its inverting input and zero on the inverting input. The capacitor 4 begins to discharge from the voltage from the output of the comparator 2 through the circuit resistor 9 - diode 6. When the voltage on the capacitor 4 becomes close to zero, the output edge of the output pulse is formed at the output of the operational amplifier 3.

Element 13 recharge can be performed on a single resistor or, as shown in the drawing, on two resistors and two diodes. In this case, it is possible to set different constants of the charge and discharge times of the capacitor 4, and, consequently, to set the necessary coefficient for increasing the duration of the output pulse compared to the duration of the input pulse.

If greater linearity is required, controlled current generators can be switched on either in transistors or on operational amplifiers in series with the diodes in the overcharge element 13.

Limiter 10 provides control of the pulse expansion ratio. In this case, different elements will be supplied to the diode of the recharge element 13, with different polarities, voltages, and, consequently, there will be different recharge rates of the capacitor 4.

Claims (1)

Invention Formula A pulse expander containing an input bus, an output bus, a first operational amplifier, a diode, the first whose output is connected to the first output of a recharge element and the first capacitor plate, the second facing of which is connected to a common bus, characterized in that impulses, in-one control bus, limiter and second operational amplifier, the noninner input of which is connected to the common bus, the output is connected to the second output of the recharging element, and input - with input bus and non-inverting input of the first operational amplifier, the inverting input of which is connected to the first output of the recharge element, and the output is connected to the output bus, while the second output of the recharge element is connected to the output of the limiter, the input of which is connected to the control bus. fa g 2