SU411628A1 - - Google Patents

Description

one

The invention relates to the field of radio engineering and can be used in electronic devices (counters) intended for converting time intervals into digital code, in particular for converting information in television automation systems, analog-code converters with intermediate conversion of an analog signal into a time interval. in small-sized digital voltmeters with double integration, as well as for range conversion received from radar stations.

Time interval to digital converters are known, comprising an electronic counter, a control trigger, and two coincidence elements.

A disadvantage of the known converters is the low speed.

In order to increase speed, the proposed converter additionally contains an inverting cascade, the element "AND-NOT and the element" OR-NOT, whose inputs are connected to the output of the first element of the match and through the second element of the match - to the output of the element "AND-NOT, and the output of the element" OR -NOT connected to the first input of the NAND element and through the inverting cascade to one of the inputs of the first match element, the second input, which is connected to the second input of the AND element and to the output of the control trigger.

The drawing shows a diagram of the proposed time interval converter into a digital code.

The converter contains the element "AND-

NOT 1, inverting cascade 2, elements

match 3, 4, the logical element "OR-

NOT 5, bits of electronic meters 6, 7

and trigger 8 control.

The Converter operates as follows.

In the initial state, at the output of the control trigger 8, a "single potential which is supplied to the corresponding; and the inputs of the coincidence element 4 and the element NOT 1." Zero potentials on the high-order devices of the device are set by applying a zero pulse. At the same time, at the output of the element "OR-NOT 5, a single potential is established, and at the outputs of the element" AND-NOT 1 and the ventilation cascade - "zero potentials.

The match element 3 is closed, and the input element "OR-NOT 5 counting pulses are not received.

When a start pulse arrives, a zero potential appears at the output of the control trigger 8 at its output, which will close a match element 4 on one of the inputs

The element "AND-NOT 1. At the output of the latter, a" single potential is established that permits the passage of electronic counters 6, 7 into the bits through the open element "OR-NOT 5 input counting pulses. In television automation systems, in radar information conversion devices, analog-code converters with intermediate conversion of an analog signal to a time interval in digital voltmeters with double integration and a number of other devices, the trigger pulse is synchronized by counting pulses. Therefore, their relative position in time cannot be random and is determined.

A counting pulse, which coincides in time with a start pulse, through the open element 3 coincides with the input element OR OR NOT 5. During the operation of the counting pulse, the output OR OR NO 5 is set to a "zero potential, which closes the element" AND-NOT 1 and inverted by an inverted cascade. At the output of the inverting stage 2, a "single potential" is established at this time. Upon termination of the counting pulse, at the output of the element "OR-NE 5" a single potential is received at the discharge input of the electronic counter 6. The output of this discharge is recorded as "a single potential. Upon receipt of the subsequent counting pulses in the electronic counter 6, information accumulates until a stop pulse arrives at the input of the control trigger 8. By this time, the N output is fixed at the output of the converter, which corresponds to the time interval.

In this case, two cases are possible: the stopping impulse does not coincide in time with the next counting impulse; the stop pulse arrives during the action of the counting pulse.

In the first case, after the appearance of a "single potential at the output of the control trigger 8, the output of the element" AND-NOT 1 is set to "a zero potential, since at its inputs there is a" single potential. The coincidence element is closed, and the counting pulses do not enter the converter. In this state, at the output of the first bit of the converter, a "zero potential" is detected.

In the second case, after the appearance of a "single potential at the output of the control trigger 8, the zero potential is acting at the output of the element" OR-NOT 5 ". At the same time

the output of the inverting cascade 2 occurs "a single potential.

Thus, at the inputs of the coincidence element 4, "single potentials which support the output of the element

"OR-NOT 5" zero potential. Although the coincidence element 3 is open, the input counting pulses do not change the state of the logical element OR NOT 5. A single potential is detected on the output bus of the converter.

In such a state, the circuit is in place before the zeroing pulse arrives.

Subject invention

A time converter to a digital code containing an electronic counter, a control trigger and two coincidence elements, characterized in that, in order to increase speed, it contains an inverting cascade, the element "AND NOT, and the element" OR - NOT, the inputs of which are connected to the output of the first element of the match and through the second element of the match with the output of the element "AND-NO, and the output of the element OR is NOT connected to the first input of the element" AND-NO and through the inverting cascade to one of the inputs of the first element of the match, the second input th is connected to the second input element "AND-

NOT with control trigger output.

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