SU372662A1 - DEVICE FORMATION RECTANGULAR - Google Patents

Description

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The invention relates to a pulse technique and can be used to generate pulses with a large range of duration, in particular to create pulse generators on integrated circuits.

A device for generating rectangular pulses is known, which contains a matching circuit with a trigger; valve-expander with a semiconductor diode and time; named by a capacitor connected to the emitter-collector junction of the output transistor, in the emitter circuit of which an adjustable bias source is included; element AND-OR-NOT, one of the inputs of which is connected to the trigger input and the common input of the device.

This device has a small range of control of the pulse duration, a large permissible duty cycle and low noise immunity.

The aim of the invention is to provide a smooth adjustment of the duration of the rectangular pulses.

For this, the collector of the output transistor of the expander valve, one of the plates of the time of the driving capacitor and the cathode of the semiconductor diode are connected to one of the inputs of the coincidence circuit, the other input of which is connected to the output of the AND-OR- element

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NOT, and the trigger output is connected to another input of the AND-OR-NOT element.

The drawing shows a schematic diagram of the proposed device. The device contains a coincidence circuit 1, valve expander 2, / 5-trigger 3, element 4 AND-OR-NOT, reverse current diode 5, adjustable bias source 6, filter capacitor 7, time setting capacitor 8 and

valve flapper 9.

The initial state / 5-trigger 5 is zero. A positive impulse arriving at the input of the imaging device flips the / 5-flip-flop 3 and opens the output transistor of the expander valve 9. The initial potential set by the source 6 is set on the capacitor 8. After the input impulse decreases, the output level of the element 4 is set and

the front edge of the output pulse. With a delay determined by the charge time of the capacitor 8 by the current of the coincidence circuit (from the initial potential to the potential of the trigger threshold of the RS flip-flop 3), the latter is put into "O. At the same time a single level on

its zero output is unlocked by element 4, and on

the output of the element is formed by the decline of the output

positive momentum.

The match / lock circuit and the condenser 8 is gradually discharged by reverse current. Since the potential of capacitor 8 cannot become lower than the potential of source 6 by more than the magnitude of the voltage drop across diode 5, capacitor 8 can be quickly measured when the next trigger pulse arrives.

Subject invention

A device for generating direct pulses containing a trigger coincidence circuit, an expander valve with a semiconductor diode and a time by a driving capacitor connected to the emitter-collector junction of the output transistor, in the emitter circuit of which an adjustable bias source is included, the AND-OR-HE element is one of the inputs of which are connected to the trigger input and the common input of the device, characterized in that, in order to smoothly adjust the duration of rectangular pulses, the collector of the output transistor of the valve iritel, one of the plates of the driving time of the capacitor and the cathode of a semiconductor diode connected to one input of the coincidence circuit, the other input of which is connected to the output I-OR-NO element, and a trigger output connected to another input of AND-OR-NO.

Output

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