SU809557A1 - Code-to-time interval converter - Google Patents

Description

(54) TIMER INTERVAL CODE CONVERTER

The invention relates to a pulse technique and can be used in automatic measuring systems. A known converter is a code-time interval containing a pulse generator, a code register connected via gates to the counter inputs, the outputs of which are connected to the inputs of the comparison element, the output of which is connected to one input of the controlling trigger, two elements, two 0-triggers and the OR element, and the direct and inverse outputs of the generator are connected to the synchronization inputs of 0-flip-flops directly, and to the inputs of the AND elements via a switch, the second inputs of the H-switch from the AND elements are connected to the direct outputs of the O-flip-flops, and The input through the OR element is connected to the counting input of the counter O sxofsfn of the flip-flops connected to the output of the control trigger, the R input of each D-flip-flop is connected to the inverse output of the other. The disadvantage of the device is its limited functionality. Also known is a time-to-time converter, which provides a pulse generator, the direct output of which is connected to one input of the AND element, another input of which is connected to the output of the control trigger, and the output of the element AND connected to the input of the counter, the coincidence element, frequency divider, additional An element, one input of which is connected via a delay line to the output of a matching circuit element, and the other input connected to an inverse output of a pulse generator 2j. This device is characterized by an increased accuracy of code conversion to a time interval, however, it does not allow to change the discreteness of the time interval formation differently than the frequency of the filling pulses, which limits the functional capabilities and leads to a decrease in the accuracy of the transformation. The purpose of the invention is to expand the functionality of the device. The goal is achieved in that a known code converter in a time interval containing a pulse generator, the output of which is connected to the input of the first element AND, the output of which is connected to the first input of the pulse counter, the control trigger and the second element AND, the additional element OR is added, an additional counter and a switch, the inputs of which are connected respectively to the outputs of the additional counter and the outputs of the information source, and the output to the control input triggering and to the first input of the second And, the second input of which is connected to the start-up bus and the zero input input of the additional pulse counter, and the output to the first input of the OR element, the second input of which is connected to the inverse output of the control trigger, and the output to the second input of the first X element output device, the output of the pulse counter is connected to its recording input and a single control trigger input, the counting input of which is connected to the output of the pulse generator and the direct output to the input of an additional pulse counter, the setup inputs with the pulse pulses are connected to the outputs of the information source.

The drawing shows a structural electrical circuit of the device.

The code to time converter comprises a read pulse generator 1, a pulse counter 2, a first AND 3 element, a control trigger 4, a second AND 5 element, an OR 6 element, an additional counter 7, and a controlled switch 8.,

The counter 7 together with the managed switch 8 serves to increase the duration of the interval formed by counter 2 and the control trigger 4 a specified number of times defined by the code applied to the input of the switch 8. It is most convenient to choose this multiplicity equal to R 10 (where m "O 1, 2, 3...).

The code converter works in the time interval of the ladder in a dim way.

Before the trigger pulse arrives, counter 2 records the number n corresponding to the code supplied to its installation inputs from the information source, in the additional counter 7 is the number R-1, at which the output of switch 8 has a low level signal defined by a code applied to the inputs switch from the source of information.

On the negative edge of the trigger pulse, which enters the input of the installation O of the counter 7 and the input of the logic element 5, the counter 7 is set to, and the output of the switch 8 is a positive level, which arrives at the raresolutions of the trigger input 4, preparing it to operate on the negative the front of the first pulse of the generator, coming after the negative front of the triggering pulse. When this pulse arrives, the trigger 4 triggers and at its inverse output a high level signal appears, which goes to the element OR 6 and then includes the first, element AND 3. Then the counting of pulses by the counter 2 begins, which is triggered by the positive edge of the pulses r incoming from the output of the first element And 3.

After counting the n pulses, the counter 2 becomes zero, and with the arrival of the negative front (n + 1) th pulse, a short negative pulse appears at its output, which sets the counter 2 to its initial state and, at the input to the setup 1 of the trigger 4, changes its state, while the first element And 3 is maintained in the open state by a high level signal coming from the output of the switch 8 through the logic elements 5 and b, and therefore with the arrival of a positive front (n + 1) -th pulse, the counter 2 starts again score. The negative front of the (n + 2) -th pulse, arriving at the counting input of trigger 4, switches it, while the contents of the additional counter 7 are incremented by one, and so on until the arrival of fn (kl) + 1) -th pulse, at the end which, in the additional counter, write the number k-1, and a low level signal appears at the output of switch 8, after which the first element 3 is kept in the open state only by a high level signal received through the element 6 from the output of trigger 4.

0 After the arrival of the nk-ro pulse, the counter 2 becomes zero, and with the arrival of a negative pulse front nk + 1, the trigger 4 is triggered and the element OR is set to a low level signal, this moment corresponds to the end of the time interval.

The pulse duration at the output of the circuit, taking into account the error, is equal to

T. 4- t + t

 f 4i CHs "jicnw

T - pulse duration on

converter output; f jy - filling pulse rate

t,; - switching time trigly j.gp „d„ „J ,, JJ3

. 1 to O, respectively;

Claims (2)

The propagation time is from the "MSP" differential difference from the counting input of counter 2 to its output. Analyzing the resulting expression, we can conclude that the absolute error in the formation of the time interval practically does not exceed the value of tj pfjonP (the values of and tj (j are opposite in sign and approximately equal). Thus, the device with high conversion accuracy has wider possibilities. Formula of the Invention A code transformer into a time interval containing an impulse generator, the output of which is connected to the input of the first AND element, the output of which is connected to the first input pulse counter, control trigger and second AND element, characterized in that, in order to expand its functionality, an OR element, an additional counter and a commator are added, the inputs of which are connected respectively to the outputs of the additional counter and the outputs of the information source, and the output - with the enable input of the control trigger and with the first input of the second element And the second input of which is connected to the startup bus and the installation input zero of the additional pulse counter, and the output to the first input OR, the second input of which is connected to the inverted output of the control trigger, and the output of the second input of the first element I and the device output, the output of the pulse counter is connected to its recording input and the single input of the control trigger, the counting input of which is connected to the output of the pulse generator, and my output is with the input of an additional pulse counter, the installation inputs of the pulse counter are connected to the outputs of the inLormation source. Sources of information taken into account in the examination 1. USSR author's certificate number 508924, cl. H 03 K 13/04, 25.10.74. 2. Authors certificate of the USSR 363207, cl. H 03 K 13/20, 05.24,71 (prototype).